WO2022228334A1 - 电力系统和电力系统的控制方法 - Google Patents
电力系统和电力系统的控制方法 Download PDFInfo
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- WO2022228334A1 WO2022228334A1 PCT/CN2022/088722 CN2022088722W WO2022228334A1 WO 2022228334 A1 WO2022228334 A1 WO 2022228334A1 CN 2022088722 W CN2022088722 W CN 2022088722W WO 2022228334 A1 WO2022228334 A1 WO 2022228334A1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for AC mains or AC distribution networks
- H02J3/38—Arrangements for feeding a single network from two or more generators or sources in parallel; Arrangements for feeding already energised networks from additional generators or sources in parallel
- H02J3/381—Dispersed generators
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for AC mains or AC distribution networks
- H02J3/28—Arrangements for balancing of the load in networks by storage of energy
- H02J3/32—Arrangements for balancing of the load in networks by storage of energy using batteries or super capacitors with converting means
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for AC mains or AC distribution networks
- H02J3/38—Arrangements for feeding a single network from two or more generators or sources in parallel; Arrangements for feeding already energised networks from additional generators or sources in parallel
- H02J3/46—Controlling the sharing of generated power between the generators, sources or networks
- H02J3/466—Scheduling or selectively controlling the operation of the generators or sources, e.g. connecting or disconnecting generators to meet a demand
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2101/00—Supply or distribution of decentralised, dispersed or local electric power generation
- H02J2101/20—Dispersed power generation using renewable energy sources
- H02J2101/22—Solar energy
- H02J2101/24—Photovoltaics
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2101/00—Supply or distribution of decentralised, dispersed or local electric power generation
- H02J2101/20—Dispersed power generation using renewable energy sources
- H02J2101/22—Solar energy
- H02J2101/24—Photovoltaics
- H02J2101/25—Photovoltaics involving maximum power point tracking control for photovoltaic sources
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2103/00—Details of circuit arrangements for mains or AC distribution networks
- H02J2103/30—Simulating, planning, modelling, reliability check or computer assisted design [CAD] of electric power networks
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
Definitions
- the present application relates to the field of power systems, and more particularly, to power systems and control methods of power systems.
- the present application provides an electric power system and a control method of the electric power system, which can improve the reliability of the operation of the electric power system.
- a power system in a first aspect, includes N DC coupling units, N DC bus bars, and a controller, the N DC coupling units are in one-to-one correspondence with the N DC bus bars, and the N DC bus bars are in one-to-one correspondence.
- the N DC coupling units are used to supply power to the power grid, and each DC coupling unit in the N DC coupling units includes an energy unit, and the energy unit is used to generate electric energy, and N is a positive integer; the overall controller is used for: Acquire the total grid-connected demand power of the power grid, where the total grid-connected demand power is the grid-connected power required by the grid; obtain the first limit value of the N DC coupling units, where the first limit value is used for Indicate the maximum discharge power that the energy unit in each DC coupling unit can provide to the power grid; according to the total grid access demand power and the first limit value of the N DC coupling units, determine the N DC coupling units.
- the first grid-connected power value refers to the power value of the input grid allocated to the energy unit in each DC coupling unit, wherein at least one DC coupling unit in the N DC coupling units is in The first limit state, where the first limit state means that the value of the first access power allocated to the DC coupling unit is equal to the corresponding first limit value.
- the general controller in the power system can obtain the maximum discharge power that the energy unit in the DC coupling unit can currently provide to the grid, that is, the first limit value, and the general controller determines the maximum discharge power according to the first limit value.
- the total grid-connected demand power assigns the first grid-connected power value to each DC coupling unit, which can prevent the power system in the power system from reducing the reliability of the power system operation due to exceeding the limit, thereby improving the reliability of the power system operation.
- each of the N DC coupling units further includes an inverter unit, and the inverter unit is configured to receive the received signal through the DC bus.
- the electrical energy output by the energy unit, and after the electrical energy is converted from DC to AC, to provide electrical energy to the power grid; the overall controller is specifically used to: determine the minimum value of the following items as the first limit of each DC coupling unit.
- Amplitude the first power value of each DC coupling unit, the second power value of each DC coupling unit, wherein the first power value is the maximum discharge power of the energy unit in each DC coupling unit, the The second power value is the maximum discharge power of the inverter unit in each DC coupling unit.
- the overall controller takes the minimum value among the first power value and the second power value of each DC coupling unit as the first amplitude limiting value of the DC coupling unit, so as to be consistent with the total distribution according to the rated power.
- the first grid-connected power value is allocated to each DC coupling unit according to the first limit value to the total grid-connected demand power, which can further improve the utilization rate of electric energy generated by the energy unit of the power system.
- the overall controller is specifically configured to: perform multiple rounds of first iterative calculations to determine the first grid-connected power value of the N DC coupling units, so Each round of the first iterative calculation in the multiple rounds of the first iterative calculation includes: determining L 1 first DC coupling units, and the first DC coupling units are not assigned the first DC coupling unit in the previous first iterative calculation.
- the DC coupling unit of the grid access power value, the L 1 is a positive integer and L 1 ⁇ N; the first candidate grid access power values of the L 1 first DC coupling units are calculated, and the first candidate grid access power value is Determined according to the total grid-connected demand power and the first power value of the L 1 DC coupling units, the first power value is the maximum discharge power that can be provided by the energy unit in each DC coupling unit; according to the The first candidate grid access power value and the first amplitude limit value of the L 1 first DC coupling units are determined, and the first grid access power value of the L 1 first DC coupling units is determined.
- multiple rounds of the first iterative calculation can be used to assign the first grid-connected power value to each DC coupling unit, thereby improving the reliability of the power system operation.
- the general controller is specifically configured to: determine L 2 second DC coupling units among the L 1 first DC coupling units, and the The value of the first candidate grid-connected power of the second DC coupling unit is greater than or equal to its corresponding first limit value, and the L 2 is a positive integer; determine the first grid-connected power of the L 2 second DC coupling units value, wherein the L 2 second DC coupling units are in the first amplitude limiting state.
- the first candidate grid-connected power value obtained by calculation is not directly used as the power value of the input grid allocated to the energy unit in each DC coupling unit, but it is determined that the power supply in the first limit state is There are L 2 second DC coupling units, and the DC coupling units in the first amplitude limiting state are allocated the corresponding first amplitude limiting value as the first grid-connected power value, so that the reliability of the power system operation can be improved.
- the overall controller is specifically configured to: determine that the first candidate grid access power values of the L 1 first DC coupling units are all smaller than their corresponding first DC coupling units. an amplitude limit value; determining the first grid-connected power value of the L 1 first DC coupling units to its corresponding first candidate grid-connected power value.
- the general controller is specifically configured to: satisfy the following conditions, and determine the first candidate grid-connected power of the L 1 first DC coupling units:
- P bus_energy_to_grid_j represents the first candidate grid access power value of the jth first DC coupling unit in the L 1 first DC coupling units
- P pref_1 represents the reference grid access demand power
- the reference grid access demand power is the The difference between the total grid access demand power and the first allocated power
- the first allocated power is the sum of the first grid access power values that have been allocated to the DC coupling unit in the previous first iterative calculation
- P bus_max_energy_j represents the L
- the first power value of the jth first DC coupling unit in one first DC coupling unit represents the sum of the first power values of the L 1 first DC coupling units, 1 ⁇ j ⁇ L 1 .
- the first candidate grid-connected power value of the first DC coupling unit in a certain round of iterative calculation is smaller than its corresponding first amplitude limit value, that is, in a certain round of calculation, the first DC coupling unit
- the coupling units are all in the first amplitude limiting state, then the first grid-connected power value of the L 1 first DC coupling units can be determined to be their corresponding first candidate grid-connected power values, which can further improve the power generation capacity of the power system energy units. utilization.
- a method for controlling a power system where the power supply system includes N DC coupling units, N DC bus bars, and a controller, where the N DC coupling units are used to supply power to a power grid, wherein the The N DC coupling units are in one-to-one correspondence with the N DC bus bars, each DC coupling unit in the N DC coupling units includes an energy unit, and the energy unit is used to generate electrical energy, N is a positive integer, and the The method includes: acquiring, by the controller, total grid-connection demand power of the power grid, where the total grid-connection demand power is the grid-connecting power required by the grid; and the controller acquiring a first limit of the N DC coupling units value, the first limit value is used to indicate the maximum discharge power that the energy unit in each DC coupling unit can provide to the grid; the controller is based on the total grid access demand power and the N DC coupling units the first amplitude limit value, which determines the first grid-connected power value of the N DC coupling units, where the first
- the general controller in the power system can obtain the maximum discharge power that the energy unit in the DC coupling unit can currently provide to the grid, that is, the first limit value, and the general controller determines the maximum discharge power according to the first limit value.
- the total grid-connected demand power assigns the first grid-connected power value to each DC coupling unit, which can prevent the power system in the power system from reducing the reliability of the power system operation due to exceeding the limit, thereby improving the reliability of the power system operation.
- each of the N DC coupling units further includes an inverter unit, and the inverter unit is configured to receive the received signal through the DC bus.
- the controller determines the N DC coupling units according to the total grid access demand power and the first amplitude limit value of the N DC coupling units
- the first grid-connected power value includes: the controller performs multiple rounds of first iterative calculation to determine the first grid-connected power value of the N DC coupling units.
- An iterative calculation includes: the controller determines L 1 first DC coupling units, where the first DC coupling units are DC coupling units that have not been assigned the first grid-connected power value in the previous first iterative calculation,
- the L 1 is a positive integer and L 1 ⁇ N;
- the controller calculates a first candidate grid-connected power value of the L 1 first DC coupling units, and the first candidate grid-connected power value is based on the total The power required for access to the grid and the first power value of the L 1 DC coupling units are determined, and the first power value is the maximum discharge power that can be provided by the energy unit in each DC coupling unit;
- the controller is based on the The first candidate grid access power value and the first amplitude limit value of the L 1 first DC coupling units are determined, and the first grid access power value of the L 1 first DC coupling units is determined.
- the controller determines the L according to the first candidate grid-connected power values and the first limit value of the L 1 first DC coupling units
- the first grid-connected power value of 1 first DC coupling unit including: the controller determines L 2 second DC coupling units among the L 1 first DC coupling units, and the second DC coupling units
- the value of the first candidate grid-connected power of the unit is greater than or equal to its corresponding first limit value, and the L 2 is a positive integer; the controller determines the first grid-connected power of the L 2 second DC coupling units value, wherein the L 2 second DC coupling units are in the first amplitude limiting state.
- the controller determines the L according to the first candidate grid-connected power values and the first limit value of the L 1 first DC coupling units
- the first grid-connected power value of one first DC coupling unit includes: determining that the first candidate grid-connected power values of the L 1 first DC coupling units are all smaller than their corresponding first limit values; determining the The first grid-connected power values of the L 1 first DC coupling units are their corresponding first candidate grid-connected power values.
- the controller calculating the first candidate grid-connected power values of the L 1 first DC coupling units includes: satisfying the following conditions, determining the L 1 first DC coupling units The first candidate grid-connected power of the first DC-coupling unit:
- P bus_energy_to_grid_j represents the first candidate grid access power value of the jth first DC coupling unit in the L 1 first DC coupling units
- P pref represents the reference grid access demand power
- the reference grid access demand power is the The difference between the total grid access demand power and the first allocated power
- the first allocated power is the sum of the first grid access power values that have been allocated to the DC coupling unit in the previous first iterative calculation
- P bus_max_energy_j represents the L
- the first power value of the jth first DC coupling unit in one first DC coupling unit represents the sum of the first power values of the L 1 first DC coupling units, 1 ⁇ j ⁇ L 1 .
- a method for controlling a power system is provided.
- the method is applied to a power system.
- the power system includes N DC coupling units, N DC bus bars, and an overall controller.
- the N DC coupling units are used for In order to supply power to the power grid, wherein the N DC coupling units correspond to the N DC bus bars one-to-one, and each DC coupling unit in the N DC coupling units includes an energy storage unit, and the energy storage unit uses For storing electric energy, N is a positive integer, and the method includes: the general controller obtains the grid-connected demand power of energy storage from the power grid, and the energy storage grid-connected demand power refers to that the energy storage unit is required to provide the grid The grid access power; the overall controller obtains the second limit value of the N DC coupling units, and the second limit value is used to indicate the maximum value that the energy storage unit in each DC coupling unit can provide to the power grid Discharge power; the overall controller determines the second grid-connected power value of each DC-coupling unit according to the energy storage grid-
- the general controller in the power system can obtain the maximum discharge power that the energy storage unit in the DC coupling unit can currently provide to the grid, that is, the second limit value, and the general controller can obtain the second limit value according to the second limit value.
- the second grid-connected power value is allocated to each DC coupling unit for the energy storage grid-connected power, which can prevent the reliability of the power system operation from decreasing due to the power devices in the power system exceeding the limit, thereby improving the reliability of the power system operation.
- the energy storage units in the power system can be discharged in a balanced manner, improving the life cycle of the power devices in the energy storage units.
- each of the N DC coupling units further includes an inverter unit, and the inverter unit is configured to receive the received signal through the DC bus.
- the overall controller uses the minimum value among the second power value and the third power value of each DC coupling unit as the second amplitude limiting value of the DC coupling unit, which can avoid the power in the power system. Because the device exceeds the limit, the reliability of the operation of the power system is reduced, so that the reliability of the operation of the power system can be improved.
- each of the N DC coupling units further includes an inverter unit and an energy unit, the energy unit is used to generate electrical energy, the The inverter unit is configured to receive the electrical energy output by the energy unit and/or the energy storage unit through the DC bus, and provide electrical energy to the power grid after converting the electrical energy from DC to AC, and the general controller obtains the N The second limit value of each DC coupling unit, including: the overall controller determines the minimum value of the following items as the second limit value of each DC coupling unit: the third power value of each DC coupling unit, The residual discharge power value of each DC coupling unit, wherein the third power value is the maximum discharge power of the energy storage unit in each DC coupling unit, and the residual discharge power value is the second power value of each DC coupling unit The power value minus the first grid-connected power value, the second power value is the maximum discharge power of the inverter unit in each DC coupling unit, and the first grid-connected power value refers to the energy unit in each DC
- the overall controller takes the minimum value among the second power value and the fourth power value of each DC coupling unit as the second limiter of the DC coupling unit
- the value of the power system can prevent the power device in the power system from reducing the reliability of the power system operation due to exceeding the limit, so that the reliability of the power system operation can be improved.
- the general controller determines the N DCs according to the grid-connected demand power of the energy storage and the second amplitude limit values of the N DC coupling units
- the second grid-connected power value of the coupling unit includes: the overall controller performs multiple rounds of second iterative calculation to determine the second grid-connected power value of the N DC coupling units.
- Each round of the second iterative calculation includes: the overall controller determines M 1 third DC coupling units, where the third DC coupling units are DC couplings that have not been assigned the second grid-connected power value in the previous second iterative calculation unit, the M 1 is a positive integer and M 1 ⁇ N; the overall controller calculates the second candidate grid access power value of the M 1 third DC coupling units, and the second candidate grid access power value is based on the It is determined by the required power of the energy storage into the grid and the first energy value of the N DC coupling units, where the first energy value is the electric energy currently stored by the energy storage unit in each DC coupling unit; the overall controller is based on The second candidate grid access power value and the second amplitude limit value of the M 1 third DC coupling units are used to determine the second grid access power value of the M 1 third DC coupling units.
- the overall controller determines the M according to the second candidate grid-connected power values and the second limiting value of the M 1 third DC coupling units
- the second grid-connected power value of one third DC coupling unit including: the overall controller determines M2 fourth DC coupling units among the M1 third DC coupling units, and the fourth DC coupling unit
- the value of the second candidate grid-connected power is greater than or equal to its corresponding second limit value, and the M 2 is a positive integer; the overall controller determines the second grid-connected power of the M 2 fourth DC coupling units value, wherein the M 2 DC coupling units are in the second amplitude limiting state.
- the overall controller determines the M according to the second candidate grid-connected power values and the second limiting value of the M 1 third DC coupling units
- the second grid-connected power value of one third DC coupling unit includes: determining that the third candidate grid-connected power values of the M 1 third DC coupling units are all smaller than their corresponding second amplitude limiting values; determining the M 1
- the second grid access power value of the third DC coupling unit is its corresponding second candidate grid access power value.
- the overall controller calculates the second candidate grid-connected power values of the M 1 third DC coupling units, including: determining the reference energy storage grid-connected demand power, so The reference energy storage grid-connected demand power is the difference between the energy storage grid-connected demand power minus the sum of the second grid-connected power values that have been allocated to the DC coupling unit in the previous second iterative calculation;
- P bus_bat_to_grid_j represents the second candidate grid connection power value of the jth third DC coupling unit among the M 1 third DC coupling units
- P pref_2 represents the reference energy storage grid connection demand power
- the reference energy storage grid connection demand power is the difference between the energy storage grid-connected demand power minus the sum of the second grid-connected power values that have been allocated to the DC coupling units in the previous second iterative calculation
- SOE bus_j represents the M 1 third DC-coupling units in the
- the first energy value of the jth third DC coupling unit represents the sum of the first energy values of the M 1 third DC coupling units, 1 ⁇ j ⁇ M 1 .
- the second candidate grid-connected power value obtained by calculation is not directly used as the power value of the input grid allocated to the energy storage unit in each DC coupling unit, but it is determined to be in the second limit state
- the M 2 fourth DC coupling units are allocated to the DC coupling units in the second limiting state with the corresponding second limiting value as the second grid-connected power value, so that the reliability of the power system operation can be improved.
- a power system in a fourth aspect, includes N DC coupling units, N DC bus bars, and an overall controller, the N DC coupling units are in one-to-one correspondence with the N DC bus bars, wherein , the N DC coupling units are used to supply power to the power grid, each of the N DC coupling units includes an energy storage unit, the energy storage unit is used to store electrical energy, and N is a positive integer; the The general controller is used to: obtain the grid-connected power demanded by the energy storage of the power grid, and the energy storage grid-connected demand power refers to the grid-connected power that the energy storage unit needs to provide for the grid; obtain the first power of the N DC coupling units.
- the second limit value of the DC coupling unit determines the second grid-connected power value of each DC coupling unit, where the second grid-connected power value refers to the power value of the input grid allocated for the energy storage unit in each DC coupling unit, wherein,
- the energy storage unit in at least one DC coupling unit of the N DC coupling units is in a second amplitude limiting state, and the second amplitude limiting state means that the value of the second grid-connected power allocated to the DC coupling unit is equal to its corresponding value. the second clipping value.
- the general controller in the power system can obtain the maximum discharge power that the energy storage unit in the DC coupling unit can currently provide to the grid, that is, the second limit value, and the general controller can obtain the maximum discharge power according to the first limit value.
- the second grid-connected power value is allocated to each DC coupling unit for the energy storage grid-connected power, which can prevent the reliability of the power system operation from decreasing due to the power devices in the power system exceeding the limit, thereby improving the reliability of the power system operation.
- the energy storage units in the power system can be discharged in a balanced manner, improving the life cycle of the power devices in the energy storage units.
- each of the N DC coupling units further includes an inverter unit, and the inverter unit is configured to receive the received signal through the DC bus. the electrical energy output by the energy storage unit, and after converting the electrical energy from DC to AC, supplying electrical energy to the power grid;
- the general controller is specifically configured to: the general controller acquires the second amplitude limiting value of the N DC coupling units , including: the overall controller determines the minimum value of the following items as the second limit value of each DC coupling unit: the second power value of each DC coupling unit, the third power value of each DC coupling unit , wherein the second power value is the maximum discharge power of the inverter unit in each DC coupling unit, and the third power value is the maximum discharge power of the energy storage unit in each DC coupling unit.
- each DC coupling unit in the N DC coupling units further includes an inverter unit and an energy unit, the energy unit is used for generating electrical energy, the The inverter unit is configured to receive the electrical energy output by the energy unit and/or the energy storage unit through the DC bus, and provide electrical energy to the power grid after converting the electrical energy from DC to AC; the general controller is specifically configured to obtain The second amplitude limiting value of the N DC coupling units includes: determining the minimum value of the following items as the second amplitude limiting value of each DC coupling unit: the third power value of each DC coupling unit, each The residual discharge power value of the DC coupling unit, wherein the third power value is the maximum discharge power of the energy storage unit in each DC coupling unit, and the residual discharge power value is the second power value of each DC coupling unit Subtract the first grid-connected power value, the second power value is the maximum discharge power of the inverter unit in each DC coupling unit, and the first grid-connected power value
- the controller is specifically configured to: perform multiple rounds of second iterative calculation to determine the second grid-connected power value of the N DC coupling units, the Each round of the second iterative calculation in the multiple rounds of the second iterative calculation includes: determining M 1 third DC coupling units, where the third DC coupling units are not assigned the second grid-connected power value in the previous second iterative calculation
- the DC coupling unit of the It is determined by the power required to be connected to the grid and the first energy value of the N DC coupling units, where the first energy value is the electric energy currently stored by the energy storage unit in each DC coupling unit ; according to the M1 third
- the second candidate grid access power value and the second amplitude limiting value of the DC coupling units are used to determine the second grid access power values of the M 1 third DC coupling units.
- the controller is specifically configured to: determine M 2 fourth DC coupling units among the M 1 third DC coupling units, and the fourth The second candidate grid-connected power value of the DC coupling unit is greater than or equal to its corresponding second limit value, and the M 2 is a positive integer; the second grid-connected power values of the M 2 fourth DC coupling units are determined, Wherein, the M 2 DC coupling units are in the second amplitude limiting state.
- the controller is specifically configured to: determine that the third candidate grid-connected power values of the M 1 third DC coupling units are all smaller than their corresponding second limits Amplitude; determine the second grid-connected power value of the M 1 third DC coupling units to its corresponding second candidate grid-connected power value.
- the controller is specifically configured to: determine a reference energy storage grid-connected demand power, where the reference energy storage grid-connected demand power is subtracted from the energy storage grid-connected demand power The difference between the sum of the second grid-connected power values that have been allocated to the DC coupling units in the previous second iterative calculation; the second candidate grid-connected power values of the M 1 third DC coupling units are determined when the following conditions are met:
- P bus_bat_to_grid_j represents the second candidate grid connection power value of the jth third DC coupling unit among the M 1 third DC coupling units
- P pref_2 represents the reference energy storage grid connection demand power
- the reference energy storage grid connection demand power is the difference between the energy storage grid-connected demand power minus the sum of the second grid-connected power values that have been allocated to the DC coupling units in the previous second iterative calculation
- SOE bus_j represents the M 1 third DC-coupling units in the
- the first energy value of the jth third DC coupling unit represents the sum of the first energy values of the M 1 third DC coupling units, 1 ⁇ j ⁇ M 1 .
- a power system in a fifth aspect, includes N DC coupling units, N DC bus bars, and an overall controller, the N DC coupling units are in one-to-one correspondence with the N DC bus bars, wherein , the N DC coupling units are used to transmit power with the power grid, each DC coupling unit in the N DC coupling units includes an inverter unit, and each DC coupling unit in the N DC coupling units further includes An energy unit and/or an energy storage unit, the inverter unit is configured to receive the electrical energy output by the energy unit through the DC bus, and after the electrical energy is converted from DC to AC, to provide electrical energy to the power grid, or, The inverter unit is used for absorbing the electrical energy of the power grid through the DC bus, and after converting the electrical energy from AC to DC, to provide electrical energy to the energy storage unit, the energy unit is used to generate electrical energy, and the energy storage unit uses is used to store electrical energy; the general controller is used to: obtain the discharge demand power of the N DC coupling units, where the discharge demand
- the electric energy generated by the energy unit of the DC coupling unit can be supplied to the DC coupling unit and/or other DC coupling units.
- the energy storage unit is charged, thereby reducing the power waste of the energy unit.
- the general controller is specifically configured to: obtain the total charging demand power, where the total charging demand power is allocated to the energy storage units in the N DC coupling units The total power obtained from the energy units in the N DC coupling units; the third limit value of the N DC coupling units is obtained, and the third limit value is used to indicate the energy storage in each DC coupling unit.
- the maximum charging power that the unit can provide according to the total charging demand power and the third amplitude limit value of the N DC coupling units, determine the charging demand power of each DC coupling unit, wherein the N DC coupling units At least one of the DC coupling units is in a third limit state, and the third limit state means that the charging demand power allocated to the DC coupling unit is equal to the corresponding third limit value.
- the charging demand power in each DC coupling unit can be determined according to the third limit value, so that the reliability of the operation of the power system caused by the power device in the power system exceeding the limit can be avoided.
- the reliability of the operation of the power system is improved, and the energy storage units in the power system can be charged in a balanced manner, thereby improving the life cycle of the power devices in the energy storage units.
- the overall controller is specifically configured to: perform multiple rounds of third iterative calculations to determine the charging demand power of the N DC coupling units, and the multiple Each round of the third iterative calculation in the third iteration calculation includes: determining T 1 fifth DC coupling units, where the fifth DC coupling units are DC couplings that have not been allocated charging demand power in the previous third iteration calculation unit, the T 1 is a positive integer and T 1 ⁇ N; the candidate charging demand power of the T 1 fifth DC coupling units is calculated, and the candidate charging demand power is based on the total charging demand power and the N
- the second energy value is determined by the second energy value of each DC coupling unit, the second energy value is the difference between the total amount of storable electric energy value and the stored electric energy value of the energy storage unit in each DC coupling unit; according to the T The candidate charging demand power of one fifth DC coupling unit and the third amplitude limit value determine the charging demand power of the T 1 fifth DC coupling units.
- the general controller is specifically configured to: determine T 2 sixth DC coupling units among the T 1 fifth DC coupling units, and the third The candidate charging demand power of the six DC coupling units is greater than or equal to its corresponding third limit value, and the T 2 is a positive integer; determine the charging demand power of the T 2 sixth DC coupling units, wherein the T 2 The two sixth DC coupling units are in the third amplitude limiting state.
- the general controller is specifically configured to: determine that the candidate charging demand powers of the T 1 fifth DC coupling units are all smaller than their corresponding third limiters value; determine the charging demand power of the T 1 fifth DC coupling units as its corresponding candidate charging demand power.
- the general controller is specifically configured to: determine a reference charging demand power, where the reference charging demand power is the charging demand power minus the third previous The difference between the sums of the charging demand powers that have been allocated to the DC coupling units in the iterative calculation; the candidate charging demand powers of the T 1 fifth DC coupling units are determined when the following conditions are met:
- p bus_bat_charge_j represents the candidate charging demand power of the jth fifth DC coupling unit in the T 1 fifth DC coupling units
- P pref_3 represents the reference total charging demand power
- the reference total charging demand power is the charging The difference between the demand power minus the sum of the charging demand powers that have been allocated to the DC coupling units in the previous third iterative calculation
- SOE bus_able_j represents the jth fifth DC coupling unit among the T 1 fifth DC coupling units
- the second energy value of represents the sum of the second energy values of the T 1 fifth DC coupling units, 1 ⁇ j ⁇ T 1 .
- the general controller is specifically configured to: determine the exchange power of the N DC coupling units, where the exchange power is the reduction of the discharge demand power of each DC coupling unit The corresponding charging demand power is determined; the adjustment demand power is determined according to the exchange power of the N DC coupling units; the first one of the N DC coupling units is determined according to the adjusted demand power and the exchange power of the N DC coupling units. Inverter power value.
- the overall controller is specifically configured to: determine a first candidate inverter of the N DC coupling units according to the exchange power of the N DC coupling units power value, the first candidate inverter power value is the sum of the exchange power of each DC coupling unit and the corresponding first grid-connected power value, or the first candidate inverter power value is the sum of each DC coupling unit The difference between the exchanged power and the absorbed power value, wherein the first input power value refers to the power value of the input grid allocated for the energy unit in each DC coupling unit, and the absorbed power value is each The power value of the power grid absorbed by the energy storage unit in the DC coupling unit; the adjusted demand power is determined according to the first candidate inverter power value of the N DC coupling units and the exchange power of the N DC coupling units.
- the overall controller is specifically configured to: determine a discharge adjustment demand value, where the discharge adjustment demand value is the first candidate inverse of the N DC coupling units The variable power value is greater than 0, and the first candidate inverter power value is greater than the corresponding second power value. The sum of the difference between the first candidate inverter power value of the DC coupling unit minus the corresponding second power value; determining the charging adjustment Demand value, the charging adjustment demand value is the fourth DC coupling unit whose first candidate inverter power value is less than 0 among the N DC coupling units, and the first candidate inverter power value is less than the corresponding fourth power value.
- the overall controller is specifically configured to: the overall controller is specifically configured to: determine an adjustment proportional value of the N DC coupling units, the adjustment proportional value is the ratio of the exchange power value of each DC coupling unit to the sum of the exchange power values of the DC coupling units whose exchange power value is greater than 0; determine the second candidate inverter power values of the N DC coupling units, wherein the first candidate The second candidate inverter power value of the DC coupling unit whose inverter power value is greater than 0 is the minimum value among the corresponding first candidate inverter power value and the corresponding second power value, and the first candidate inverter power value is less than 0.
- the second candidate inverter power value of the DC coupling unit is the maximum value among the corresponding first candidate inverter power value and the corresponding fourth power value; when it is determined that the discharge demand power is greater than the charging demand power, the exchange power value is determined.
- the first inverter power value of the DC coupling unit that is less than 0 is the difference between the corresponding second candidate inverter power value minus the product of the adjustment demand power and the corresponding adjustment proportional value, and the first inverter power value of the DC coupling unit whose exchange power is greater than 0 is determined.
- an inverter power value corresponding to the second candidate inverter power value determining that the discharge demand power is less than the charging demand power, determining that the first inverter power value of the DC coupling unit whose exchange power value is less than 0 corresponds to
- the second candidate inverter power value is determined by determining the first inverter power value of the DC coupling unit whose exchange power value is greater than 0.
- the corresponding second candidate inverter power value minus the difference between the adjusted demand power and the corresponding adjustment proportional value product .
- a method for controlling a power system is provided, the method is applied to a power system, the power system includes N DC coupling units, N DC bus bars, and a controller, and the N DC coupling units are used for Power transmission with the power grid, wherein the N DC coupling units are in one-to-one correspondence with the N DC bus bars, each DC coupling unit in the N DC coupling units includes an inverter unit, and the N DC coupling units Each DC coupling unit in the unit further includes an energy unit and/or an energy storage unit, and the inverter unit is configured to receive the electrical energy output by the energy unit through the DC bus, and perform DC to AC conversion on the electrical energy.
- the inverter unit is configured to absorb the electric energy of the power grid through the DC bus, and after the electric energy is converted from alternating current to direct current, to provide electric energy to the energy storage unit, and the energy unit uses
- the energy storage unit is used to store the electric energy
- the method includes: the controller obtains the discharge demand power of the N DC coupling units, and the discharge demand power is used to indicate the discharge demand power of each DC coupling unit.
- the first inverter power value of the unit, the first inverter power value is used to indicate the power of the inverter unit in each DC coupling unit to provide electrical energy to the grid, or the first inverter power value is used to indicate each The inverter units in each of the DC-coupled units absorb the power of the electrical energy from the grid.
- the electric energy generated by the energy unit of the DC coupling unit can be supplied to the DC coupling unit and/or other DC coupling units.
- the energy storage unit is charged, thereby reducing the power waste of the energy unit.
- the controller acquiring the charging demand power of the N DC coupling units includes: the controller acquiring a total charging demand power, where the total charging demand power is The total power obtained from the energy units in the N DC coupling units allocated to the energy storage units in the N DC coupling units; the controller obtains the third amplitude limit value of the N DC coupling units, the The three limit values are used to indicate the maximum charging power that the energy storage unit in each DC coupling unit can provide; the controller according to the total charging demand power and the third limit value of the N DC coupling units, Determine the charging demand power of each DC coupling unit, wherein at least one DC coupling unit in the N DC coupling units is in a third limit state, and the third limit state refers to the allocated power for the DC coupling unit The charging demand power is equal to its corresponding third limit value.
- the controller determines the charging demand of each DC coupling unit according to the total charging demand power and the third amplitude limit value of the N DC coupling units power, including: the controller performs multiple rounds of third iterative calculation to determine the charging demand power of the N DC coupling units, and each third iterative calculation in the multiple rounds of third iterative calculation includes: the The controller determines T 1 fifth DC coupling units, where the fifth DC coupling units are DC coupling units that have not been allocated charging demand power in the previous third iterative calculation, where T 1 is a positive integer and T 1 ⁇ N; the controller calculates the candidate charging demand power of the T 1 fifth DC coupling units, where the candidate charging demand power is based on the total charging demand power and the second energy value of the N DC coupling units It is determined that the second energy value is the difference between the total amount of storable electric energy value of the energy storage unit in each DC coupling unit and the stored electric energy value ; The candidate charging demand power of the coupling unit and
- the controller determines the T 1 th DC coupling unit according to the candidate charging demand power and the third limit value of the T 1 fifth DC coupling units
- the charging demand power of the five DC coupling units includes: the controller determines T2 sixth DC coupling units among the T1 fifth DC coupling units, and the candidate charging demand power of the sixth DC coupling unit is greater than or equal to its corresponding third amplitude limit value, the T 2 is a positive integer; the controller determines the charging demand power of the T 2 sixth DC coupling units, wherein the T 2 sixth DC coupling units The unit is in the third clipping state.
- the controller determines the T 1 th DC coupling unit according to the candidate charging demand power and the third limit value of the T 1 fifth DC coupling units
- the charging demand power of the five DC coupling units includes: determining that the candidate charging demand powers of the T 1 fifth DC coupling units are all smaller than their corresponding third limit values ;
- the charging demand power is its corresponding candidate charging demand power.
- the controller calculates the candidate charging demand powers of the T 1 fifth DC coupling units, including: determining a reference charging demand power, where the reference charging demand power is The difference value of the charging demand power minus the sum of the charging demand powers that have been allocated to the DC coupling units in the previous third iterative calculation; combining the following aspects, determine the candidate charging demands of the T 1 fifth DC coupling units power:
- P bus_bat_to_grid_j represents the first candidate charging power value of the jth fifth DC coupling unit in the T 1 fifth DC coupling units
- P max_energy_to_bat represents the reference charging demand power
- the reference charging demand power is the charging The difference between the demand power minus the sum of the charging demand powers that have been allocated to the DC coupling units in the previous third iterative calculation
- SOE bus_able_j represents the jth fifth DC coupling unit among the T 1 fifth DC coupling units
- the second energy value of represents the sum of the second energy values of the T 1 fifth DC coupling units, 1 ⁇ j ⁇ T 1 .
- the controller determines each DC coupling unit according to the discharge demand power of the N DC coupling units and the charging demand power of the N DC coupling units
- the first inverter power value of The controller determines the adjusted demand power according to the exchange power of the N DC coupling units; the controller determines the first inverter power of the N DC coupling units according to the adjusted demand power and the exchange power of the N DC coupling units value.
- the controller determines and adjusts the required power according to the exchange power of the N DC coupling units, including: the controller according to the N DC coupling units determine the first candidate inverter power value of the N DC coupling units, where the first candidate inverter power value is the sum of the exchange power of each DC coupling unit and the corresponding first grid-connected power value, or , the first candidate inverter power value is the difference between the exchange power of each DC coupling unit minus the absorbed power value, where the first grid-connected power value refers to the energy unit in each DC coupling unit
- the allocated power value of the input power grid, the absorbed power value is the power value of the absorbed power grid allocated to the energy storage unit in each DC coupling unit; the controller is based on the first candidate inverse of the N DC coupling units.
- the variable power value and the exchange power of the N DC coupling units determine the adjusted demand power.
- the controller determines the Adjusting the demand power includes: the controller determining a discharge adjustment demand value, where the discharge adjustment demand value is greater than 0, and the first candidate inverter power value is greater than 0 in the N DC coupling units.
- the controller determines the charging adjustment demand value, and the charging adjustment demand value is Among the N DC coupling units, the first candidate inverter power value is less than 0, and the fourth power value of the DC coupling unit whose first candidate inverter power value is less than the corresponding fourth power value minus the corresponding first candidate inverter power value.
- the controller determines the first inverter power value of the N DC coupling units according to the adjusted demand power and the exchange power of the N DC coupling units , including: the controller determines an adjustment ratio value of the N DC coupling units, where the adjustment ratio value is the ratio of the exchange power value of each DC coupling unit to the sum of the exchange power values of the DC coupling units whose exchange power value is greater than 0
- the controller determines the second candidate inverter power value of the N DC coupling units, wherein the second candidate inverter power value of the DC coupling unit whose first candidate inverter power value is greater than 0 corresponds to the first The minimum value of the candidate inverter power value and the corresponding second power value, the second candidate inverter power value of the DC coupling unit whose first candidate inverter power value is less than 0 is the corresponding first candidate inverter power value and the corresponding The maximum value of the fourth power values of The difference between the inverter power value and the product of the adjustment
- a method for controlling a power system is provided.
- the method is applied to a power system.
- the power system includes N DC coupling units, N DC bus bars, and an overall controller.
- the N DC coupling units are used for for absorbing power from the power grid, wherein the N DC coupling units are in one-to-one correspondence with the N DC bus bars, and each DC coupling unit in the N DC coupling units includes an energy storage unit, and the energy storage unit
- N is a positive integer
- the method includes: the overall controller obtains the absorption demand power of the power grid, and the absorption demand power is the energy storage unit in the N DC coupling units that needs to be absorbed from the power grid power; the overall controller acquires the fourth limit value of the N DC coupling units, where the fourth limit value is used to indicate the maximum charging power that each DC coupling unit can provide; the overall controller According to the absorption demand power and the fourth amplitude limit value of the N DC coupling units, the absorbed power value of the N DC coupling units is determined
- the general controller in the power system can obtain the maximum charging power that each DC coupling unit can provide, that is, the maximum charging power that the energy storage unit in the DC coupling unit can absorb from the grid currently, that is, the first charging power.
- the total controller assigns the absorbed power value to each DC coupling unit according to the fourth limit value to the absorbed demand power value, which can avoid the reliability of the power system operation caused by the power devices in the power system exceeding the limit. decrease, thereby improving the reliability of power system operation.
- each of the N DC coupling units further includes an inverter unit, and the inverter unit is configured to receive a power grid through the DC bus.
- the method further includes: acquiring, by the general controller, the fourth amplitude limiting value of the N DC coupling units, including: The overall controller determines the minimum value of the following items as the fourth limit value of each DC coupling unit: the absolute value of the fourth power value of each DC coupling unit, the fifth power value of each DC coupling unit , wherein the fourth power value is the maximum charging power of the inverter unit in each DC coupling unit, and the fifth power value is the maximum charging power of the energy storage unit in each DC coupling unit.
- the overall controller takes the minimum value among the fourth power value and the fifth power value of each DC coupling unit as the fourth amplitude limiting value of the DC coupling unit, so that the operating efficiency of the power system can be improved. reliability.
- the total controller determines the absorption of the N DC coupling units according to the absorption demand power and the fourth amplitude limit value of the N DC coupling units
- the power value includes: the total controller performs multiple rounds of fourth iterative calculation to determine the absorbed power value of the N DC coupling units, and each round of the fourth iterative calculation in the multiple rounds of fourth iterative calculation includes:
- the overall controller determines Q 1 seventh DC coupling units, where the seventh DC coupling units are not allocated in the previous fourth iterative calculation a DC coupling unit that absorbs power values, the Q 1 is a positive integer, and Q 1 ⁇ N; the overall controller calculates the first candidate absorbed power values of the Q 1 seventh DC coupling units, the first The candidate absorbed power value is determined according to the absorbed demand power and the second energy value of the Q 1 DC coupling units, where the second energy value is the storable electric energy of the energy storage unit in each DC coupling unit The difference between the total value and the stored electric energy value; the total controller determines the Q 1 seventh DC coupling unit according to the first candidate absorbed power value and the fourth limit value of the Q 1 seventh DC coupling unit The absorbed power value of the DC-coupled unit.
- the total controller determines the absorption of the N DC coupling units according to the absorption demand power and the fourth amplitude limit value of the N DC coupling units
- the power value includes: the overall controller determines Q 2 eighth DC coupling units in the Q 1 seventh DC coupling units, and the first candidate absorbed power value of the eighth DC coupling unit is greater than or equal to the The corresponding fourth amplitude limit value, the Q 2 is a positive integer; the total controller determines the absorbed power value of the Q 2 eighth DC coupling units, wherein the Q 2 eighth DC coupling units are in the fourth clipping state.
- the total controller determines the absorption of the N DC coupling units according to the absorption demand power and the fourth amplitude limit value of the N DC coupling units
- the power value includes: determining that the first candidate absorbed power values of the Q 1 seventh DC coupling units are all smaller than their corresponding fourth amplitude limiting values; determining that the absorbed power values of the Q 1 seventh DC coupling units are Its corresponding first candidate absorbed power value.
- the overall controller calculates the first candidate absorbed power values of the Q 1 seventh DC coupling units, including: determining a first reference absorbed demand power, and the The first reference absorption demand power is the difference between the absorption demand power minus the sum of the absorption power values that have been allocated to the DC coupling unit in the previous fourth iterative calculation; if the following conditions are met, determine Q 1 seventh DC coupling The first candidate absorbed power value for the cell:
- P bus_bat_from_grid_j represents the first candidate absorbed power value of the jth DC coupling unit in the Q 1 seventh DC coupling unit
- P ref_absorb represents the first reference absorption demand power
- the first reference absorption demand power is the The difference between the absorption demand power minus the sum of the absorption power values that have been allocated to the DC coupling units in the previous fourth iteration calculation
- SOE bus_able_j represents the jth seventh DC coupling in the Q 1 seventh DC coupling units the second energy value of the unit, represents the sum of the second energy values of the Q 1 seventh DC coupling units, 1 ⁇ j ⁇ Q 1 .
- the balanced discharge of the energy storage units in the DC coupling unit can be realized, and the life cycle of the power devices of the energy storage unit can be further improved.
- a power system in an eighth aspect, includes N DC coupling units, N DC bus bars and a controller, the N DC coupling units are in one-to-one correspondence with the N DC bus bars, and the The N DC coupling units are used for absorbing power from the power grid, each of the N DC coupling units includes an energy storage unit, and the energy storage unit is used to store electrical energy, and N is a positive integer; the overall control The device is used to: obtain the absorption demand power of the power grid, where the absorption demand power is the power that the energy storage unit in the N DC coupling units needs to absorb from the power grid; obtain the fourth amplitude limit value of the N DC coupling units , the fourth limit value is used to indicate the maximum charging power that each DC coupling unit can provide; according to the absorption demand power and the fourth limit value of the N DC coupling units, determine the N DC coupling units
- the absorbed power value refers to the power value absorbed from the power grid allocated to the energy unit in each DC coupling unit, wherein at least one DC coup
- the general controller in the power system can obtain the maximum charging power that each DC coupling unit can provide, that is, the maximum charging power that the energy storage unit in the DC coupling unit can absorb from the grid currently, that is, the first charging power.
- the total controller assigns the absorbed power value to each DC coupling unit according to the fourth limit value to the absorbed demand power value, which can avoid the reliability of the power system operation caused by the power devices in the power system exceeding the limit. decrease, thereby improving the reliability of power system operation.
- each of the N DC coupling units further includes an inverter unit, and the inverter unit is configured to receive a power grid through the DC bus.
- the electrical energy is converted from AC to DC, and the electrical energy is transmitted to the energy storage unit after the AC-to-DC conversion of the electrical energy;
- the overall controller is specifically configured to: determine the minimum value of the following items as the fourth limit of each DC coupling unit value: the absolute value of the fourth power value of each DC coupling unit, the fifth power value of each DC coupling unit, wherein the fourth power value is the maximum charging power of the inverter unit in each DC coupling unit, The fifth power value is the maximum charging power of the energy storage unit in each DC coupling unit.
- the overall controller is specifically configured to: perform multiple rounds of fourth iterative calculations to determine the absorbed power values of the N DC coupling units, and the multiple Each round of the fourth iterative calculation in the round of the fourth iterative calculation includes: the overall controller determines Q 1 seventh DC coupling units, the seventh DC coupling units are not allocated and absorbed in the previous fourth iterative calculation DC coupling units of power values, the Q 1 is a positive integer, and Q 1 ⁇ N; the overall controller calculates the first candidate absorbed power values of the Q 1 seventh DC coupling units, the first candidate The absorbed power value is determined according to the absorbed demand power and the second energy value of the Q 1 DC coupling units, where the second energy value is a storable electric energy value of the energy storage unit in each DC coupling unit The difference between the total amount and the stored electric energy value; the overall controller determines the Q 1 seventh DC coupling unit according to the first candidate absorbed power value and the fourth limit value of the Q 1 seventh DC coupling
- the overall controller is specifically configured to: determine Q 2 eighth DC coupling units among the Q 1 seventh DC coupling units, and the The first candidate absorbed power value of the eight DC coupling units is greater than or equal to its corresponding fourth amplitude limit value, and the Q 2 is a positive integer; the overall controller determines the absorbed power of the Q 2 eighth DC coupling units value, wherein the Q 2 eighth DC coupling units are in the fourth clipping state.
- the overall controller is specifically configured to: determine that the first candidate absorbed power values of the Q 1 seventh DC coupling units are all smaller than their corresponding fourth Limiting value; determining the absorbed power value of the Q 1 seventh DC coupling units to its corresponding first candidate absorbed power value.
- the overall controller is specifically configured to: determine a first reference absorption demand power, where the first reference absorption demand power is the absorption demand power minus the The difference between the sums of the absorbed power values that have been allocated to the DC-coupling units in the previous fourth iterative calculation; the first candidate absorbed power values of the Q 1 seventh DC-coupling units are determined when the following conditions are met:
- P bus_bat_from_grid_j represents the first candidate absorbed power value of the jth DC coupling unit in the Q 1 seventh DC coupling unit
- P ref_absorb represents the first reference absorption demand power
- the first reference absorption demand power is the The difference between the absorption demand power minus the sum of the absorption power values that have been allocated to the DC coupling units in the previous fourth iteration calculation
- SOE bus_able_j represents the jth seventh DC coupling in the Q 1 seventh DC coupling units the second energy value of the unit, represents the sum of the second energy values of the Q 1 seventh DC coupling units, 1 ⁇ j ⁇ Q 1 .
- FIG. 1 is a schematic diagram of an example of a power system applicable to the present application
- FIG. 2 is a schematic structural diagram of an example of an energy unit to which the present application is applied;
- FIG. 3 is a schematic structural diagram of an example of an energy storage unit to which the present application is applied;
- FIG. 4 is a schematic structural diagram of an example of an inverter unit to which the present application is applied;
- FIG. 5 is a schematic flowchart of allocating a first grid-connected power value to a DC coupling unit provided by the present application
- FIG. 6 is a schematic flowchart of an example of determining the first network access power value provided by the present application.
- FIG. 7 is a schematic flowchart of allocating a second grid-connected power value to a DC coupling unit provided by the present application.
- FIG. 8 is a schematic flowchart of an example of determining the second network access power value provided by the present application.
- FIG. 9 is a schematic flowchart of allocating a first inverter power value to a DC coupling unit provided by the present application.
- FIG. 10 is a schematic flowchart of determining the first inverter power value provided by the present application.
- FIG. 11 is a schematic flowchart of allocating absorbed power values to DC coupling units provided by the present application.
- FIG. 12 is a schematic flowchart of an example of determining the absorbed power value provided by the present application.
- FIG. 13 is another example of a schematic flow chart of allocating a first inverter power value to a DC coupling unit provided by the present application;
- FIG. 14 is a schematic structural diagram of a device to which the present application is applied.
- FIG. 1 shows a schematic diagram of a power system 100 provided by an embodiment of the present application.
- the power system may include at least one general controller, such as the general controller 101 shown in FIG. 1 ; the power system 100 also At least one DC coupling unit may be included, such as DC coupling units 102 to 104 shown in FIG. 1 ; the power system 100 may also include at least one DC bus, such as DC bus bars 105 to 107 shown in FIG. 1 .
- the DC coupling units 102 to 104 are in one-to-one correspondence with the DC bus bars 105 to 107 .
- the overall controller 101 can control the DC coupling units 102 to 104 . Therefore, the overall controller 101, the DC coupling units 102 to 104, and the DC bus bars 105 to 107 in FIG. 1 constitute a power system that can transmit power with the grid 108, that is to say, the DC coupling units 102 to 104 can transmit power to the grid. 108 supplies power, the DC coupling units 102 to 104 may also draw power from the grid 108 .
- each DC coupling unit includes an inverter unit, such as inverter units 1021, 1031 and 1041 shown in FIG. 1; each DC coupling unit may also include an energy unit, such as energy units 1022, 1032 shown in FIG. 1; Each DC coupling unit may also include an energy storage unit, such as the energy storage units 1033 and 1043 shown in FIG. 1 .
- the DC sides of the inverter units 1021 , 1031 and 1041 are connected to the DC busbars 105 to 107 , and the AC side is connected to the grid 108 for receiving the electrical energy output by the energy units 1022 and 1032 through the DC busbars 105 to 107 , and/or storing energy.
- the inverter units 1021 , 1031 and 1041 can also be used to absorb the electric energy of the grid 108 , and to provide electric energy to the energy storage units 1033 and 1043 through the DC bus bars 105 to 107 after the electric energy is converted from AC to DC.
- the energy units 1022 and 1032 are used to generate electrical energy, and the energy storage units 1033 and 1043 are used to store electrical energy.
- the energy unit may be a new energy unit, for example, a power device that uses solar energy, geothermal energy, wind energy, ocean energy, biomass energy, or nuclear fusion energy to generate electrical energy.
- a power device that uses solar energy, geothermal energy, wind energy, ocean energy, biomass energy, or nuclear fusion energy to generate electrical energy.
- the following is an example of an energy unit that uses solar energy to generate electricity.
- FIG. 2 is a schematic structural diagram of an energy unit 2000 provided by an embodiment of the present application.
- the energy unit 2000 can be applied to the system shown in FIG. 1 .
- the energy unit may include at least one photovoltaic cell, such as photovoltaic cells 2100 to 2300 shown in FIG. 2 ; the energy unit may also include at least one photovoltaic controller, such as photovoltaic controllers 2400 to 2600 shown in FIG. 2 .
- Photovoltaic cells 2100 to 2300 are connected to the DC bus through photovoltaic controllers 2400 to 2600 .
- the photovoltaic cells 2100 to 2300 are used to directly convert the light energy of the sun into electrical energy, such as monocrystalline silicon solar photovoltaic cells, polycrystalline silicon solar photovoltaic cells or amorphous silicon solar photovoltaic cells; photovoltaic controllers 2400 to 2600 are used to control photovoltaic cells respectively.
- a photovoltaic controller can obtain the maximum discharge power that can be provided by the corresponding photovoltaic cells, for example, the photovoltaic controller can be an MPPT controller.
- the MPPT controller can track the maximum power point of the photovoltaic cell in real time, and can control the photovoltaic cell to output electrical energy at the maximum power.
- FIG. 3 is a schematic structural diagram of an energy storage unit 3000 provided by an embodiment of the present application.
- the energy storage unit 3000 may include at least one energy storage battery, such as the energy storage batteries 3100 to 3300 shown in FIG. 3 ; the energy storage unit 3000 may also include at least one energy storage controller, such as the energy storage control shown in FIG. 3 . devices 3400 to 3600.
- the energy storage batteries 3100 to 3300 are connected to the DC bus through the energy storage controllers 3400 to 3600 .
- the energy storage batteries 3100 to 3300 can be used to store electrical energy, and can also be used to provide electrical energy, such as lead-acid batteries, lithium-ion energy storage batteries, etc.; the energy storage controllers 3400 to 3600 are respectively used to control the energy storage batteries 3100 to 3300 , which can be a DCDC controller.
- FIG. 4 is a schematic structural diagram of an inverter unit 4000 provided by an embodiment of the present application.
- the inverter unit 4000 may include at least one inverter, such as inverters 4100 to 4300 shown in FIG. 4 .
- the DC side of the inverters 4100 to 4300 is connected to the DC bus
- the AC side of the inverters 4100 to 4300 is connected to the grid
- the direction of the power on the inverters 4100 to 4300 can be from the DC bus to the grid, or It can be absorbed power from the grid to flow to the DC bus.
- the power system shown in Figure 1 can be applied to both the grid dispatching power grid and the grid dispatching absorbing power from the grid.
- FIG. 5 is a method 100 for allocating grid-connected power to an energy unit
- FIG. 7 is a method 200 for allocating grid-connected power to an energy storage unit
- FIG. 9 is a method for allocating a first inverter to an inverter unit.
- Method 300 of power The method 100 , the method 200 , and the method 300 can be independently applied to the power system, or can be combined to be applied to the power system.
- the method 100 is used to allocate grid-connected power to the energy units in the DC-coupled system.
- the energy storage unit distributes the grid power.
- the method 100 is used to allocate grid-connected power to the energy units in the DC-coupled system.
- the inverter unit distributes the first inverter power, so that the remaining electric energy of the energy unit can be delivered to the energy storage unit for storage.
- FIG. 5 is a schematic flowchart of a method 100 for allocating grid-connected power to an energy unit according to an embodiment of the present application.
- the method 100 can be applied to a power system including N DC coupling units, N DC buses, and an overall controller.
- the master controller acquires the total grid-connected demand power of the power grid.
- the total on-grid demand power is the on-grid power required by the grid.
- the overall controller acquires the first amplitude limiting values of the N DC coupling units.
- the first amplitude limit value is used to indicate the maximum discharge power that the energy unit in each of the N DC coupling units can provide to the grid.
- the total controller determines the first grid-connected power value of the N DC-coupling units according to the total grid-connected required power and the first amplitude limit values of the N DC-coupling units.
- the first grid-connected power value refers to the power value of the input grid allocated to the energy unit in each of the N DC coupling units, wherein at least one of the N DC coupling units is in the first limit Amplitude state, the first limiter state means that the value of the first access power allocated to the DC coupling unit is equal to the corresponding first limiter value.
- step S120 in FIG. 5 the manner of obtaining the first amplitude limit value in step S120 in FIG. 5 will be described with reference to the following steps S121 to S123.
- the overall controller acquires the first power values of the N DC coupling units.
- the first power value is the maximum discharge power of the energy unit in each DC coupling unit.
- the overall controller may obtain the at least one photovoltaic controller from the at least one photovoltaic controller.
- the maximum discharge power of a photovoltaic cell when the energy unit in each DC coupling unit includes at least one photovoltaic cell and at least one photovoltaic controller, the overall controller may obtain the at least one photovoltaic controller from the at least one photovoltaic controller. The maximum discharge power of a photovoltaic cell.
- the MPPT controller can provide the total controller with the maximum discharge power of its corresponding photovoltaic cell, wherein the power of the i-th photovoltaic cell in the energy unit in the j-th DC coupling unit is The maximum discharge power is p max_energy_ji .
- the maximum discharge power value provided by the MPPT controller to the total controller may be the estimated value of the discharge power of the corresponding photovoltaic cell by the MPPT controller.
- the photovoltaic cell corresponding to the MPPT controller is in a derating state, and the maximum discharge power value provided by the MPPT controller to the total controller may be the maximum discharge power after derating.
- the total controller determines the maximum discharge power of the energy unit in each of the N DC coupling units according to the maximum discharge power of the at least one photovoltaic cell, wherein the maximum discharge power of the energy unit in the jth DC coupling unit is also That is, the first power value p bus_max_energy_j is:
- the maximum discharge power of the energy unit in each DC coupling unit is the sum of the maximum discharge powers of the photovoltaic cells provided by all photovoltaic controllers in the energy unit in each DC coupling unit.
- the overall controller acquires the second power value of each of the N DC coupling units.
- the second power value is the maximum discharge power of the inverter unit in each DC coupling unit.
- the overall controller obtains the maximum discharge power of each inverter, wherein the jth The maximum discharge power of the ith inverter in the inverter unit in the DC coupling units is p pcs_max_discharge_ji .
- the overall controller determines the maximum discharge power of the inverter unit in each of the N DC coupling units according to the maximum discharge power of the at least one inverter, wherein the maximum discharge power of the inverter unit in the jth DC coupling unit
- the power, ie the second power value p bus_max_pcs_discharge_j is:
- the maximum discharge power of the inverter unit in each DC coupling unit is the sum of the maximum discharge powers of all inverters in the inverter unit in each DC coupling unit.
- S123 The overall controller determines the first amplitude limit value of each of the N DC coupling units according to the first power value of the N DC coupling units and the second power value of the N DC coupling units.
- the overall controller determines the minimum value of the following items as the first limit value of each DC coupling unit: the first power value of each DC coupling unit, the second power value.
- the first limit value p lim_1_j of the jth DC coupling unit in the N DC coupling units is:
- p lim_1_j min(p bus_max_energy_j ,p bus_max_pcs_discharge_j ) (3)
- the actual grid-connected power of the energy unit in the DC coupling unit needs to be limited by the inverter unit, so as to avoid excessive operation of photovoltaic cells, energy controllers or inverters, which will reduce the reliability of the power system.
- step S130 in FIG. 5 shows a schematic flowchart of obtaining the first network access power value.
- the overall controller performs a first iterative calculation according to the total grid-connected demand power and the first limit value of the N DC coupling units to determine the first grid-connected power value of the N DC coupling units.
- the total controller calculates the initial first candidate grid-connected power values of the N DC coupling units.
- the overall controller determines the initial first candidate power value of each of the N DC coupling units according to the following formula, wherein the initial first candidate power value of the jth DC coupling unit for:
- p bus_energy_to_grid_j represents the initial first candidate grid-connected power value of the j-th DC coupling unit among the N DC-coupling units
- p 1 represents the total grid-connected demand power
- p bus_max_energy_j represents the j-th DC-coupling unit in the N DC-coupling units.
- first power value Indicates the sum of the first power values of N DC coupling units, 1 ⁇ j ⁇ N.
- the overall controller determines L second DC coupling units among the N DC coupling units.
- the initial first candidate network access power value of the second DC coupling unit is greater than or equal to its corresponding first amplitude limit value, and L is a positive integer.
- the second DC coupling unit can be understood as a DC coupling unit in the first amplitude limiting state after this calculation.
- the overall controller makes a determination according to the L second DC coupling units.
- the overall controller determines the first grid-connected power value of the N DC coupling units to its corresponding initial first candidate grid-connected power value, and ends the first iterative calculation.
- the overall controller can assign its corresponding initial value to the energy unit in the N DC coupling units.
- the first candidate grid-connected power value enters the grid.
- the overall controller determines that the first grid-connected power value of the L second DC coupling units is its corresponding first amplitude limit value, and ends the first iterative calculation.
- the N DC coupling units are all in the first limit state, and the overall controller assigns the corresponding first limit to the energy units in the N DC coupling units. Amplitude enters the grid.
- the overall controller determines that the first grid-connected power value of the L second DC coupling units is the corresponding first amplitude limit value.
- the overall controller first allocates the first grid-connected power value to the L second DC coupling units, and then executes S1307.
- the overall controller determines L 1 first DC coupling units.
- the L 1 first DC coupling units are DC coupling units to which the first grid-connected power value has not been assigned in the previous first iterative calculation, and L 1 is a positive integer and L 1 ⁇ N.
- the first DC coupling unit can also be understood as that the first candidate network access power value calculated in the previous first iterative calculation is smaller than the corresponding first amplitude limit value.
- the general controller determines the reference grid access demand power.
- the total controller determines the reference grid-connected demand power according to the following formula:
- pre ref_1 is the reference power required for access to the network, is the sum of the first grid-connected power values of the DC coupling units that have been assigned the first grid-connected power value
- P bus_energy_to_grid_j is the first grid-connected power value of the j-th DC-coupling unit in the DC-coupling units to which the first grid-connected power value has been assigned .
- S1309 Calculate the first candidate grid-connected power values of the L 1 first DC coupling units.
- the total controller determines the first candidate grid-connected power values of the L 1 first DC coupling units according to the following formula:
- P bus_energy_to_grid_j represents the first candidate grid-connected power value of the jth first DC coupling unit in the L 1 first DC coupling units
- p bus_max_energy_j represents the jth first DC coupling unit in the L 1 first DC coupling units.
- the first power value of the DC coupling unit Indicates the sum of the first power values of the L 1 first DC coupling units, 1 ⁇ j ⁇ L 1 .
- the overall controller determines L 2 second DC coupling units among the L 1 first DC coupling units.
- the value of the first candidate network access power calculated by the L 2 second DC coupling units in S1309 is greater than or equal to the corresponding first amplitude limit value, and L 2 is a positive integer.
- S1311 The overall controller determines the first grid-connected power value of the L 2 second DC coupling units.
- the L 2 second DC coupling units are in the first amplitude limiting state, that is, the general controller determines to assign their corresponding first amplitude limiting values to the power grid for the L 2 second DC coupling units.
- the overall controller makes a determination according to the L 1 first DC coupling units and the L 2 second DC coupling units.
- the overall controller determines to end the multiple rounds of first iterative calculation.
- the L 1 first DC coupling units that have not been assigned before are all assigned their corresponding first amplitude limiting values as the first grid-connected power values in S1311.
- the overall controller determines the first grid-connected power value of the L 1 first DC coupling units, and ends the multiple rounds of first iterative calculation.
- the first grid-connected power value of the L 1 first DC coupling units is the corresponding first reference grid-connected power value.
- the general controller in the power system can obtain the maximum discharge power that the energy unit in the DC coupling unit can currently provide to the grid, that is, the first limit value, and the general controller determines the maximum discharge power according to the first limit value.
- the total grid-connected demand power assigns the first grid-connected power value to each DC coupling unit, which can prevent the power system in the power system from reducing the reliability of the power system operation due to exceeding the limit, thereby improving the reliability of the power system operation.
- FIG. 7 is a schematic flowchart of a method 200 for allocating grid-connected power to an energy storage unit according to an embodiment of the present application.
- the method 200 can be applied to a power system including N DC coupling units, N DC buses, and an overall controller.
- the general controller obtains the grid-connected energy demanded power of the power grid.
- the grid-connected demand power of the energy storage refers to the grid-connected power that the energy storage unit needs to provide for the grid.
- the overall controller acquires the second amplitude limiting values of the N DC coupling units.
- the second amplitude limit value is used to indicate the maximum discharge power that the energy storage unit in each DC coupling unit can provide to the grid.
- the overall controller determines the second grid-connected power value of each DC-coupling unit according to the grid-connected demand power of the energy storage and the second amplitude limit value of the N DC-coupling units.
- the second grid-connected power value refers to the power value of the input grid allocated for the energy storage unit in each DC coupling unit, wherein the energy storage unit in at least one DC coupling unit in the N DC coupling units is in the second limit Amplitude state, the second limiter state means that the value of the second input power allocated to the DC coupling unit is equal to its corresponding second limiter value.
- step S210 the manner of obtaining the power required for the grid connection of the energy storage in step S210 will be described with reference to the following steps S211 to S213.
- the total controller determines the total first grid-connected power value of the N DC coupling units.
- the total first grid-connected power value refers to the total power value of the input grid allocated for the energy units in the N DC coupling units.
- the overall controller may determine the first grid-connected power value of each of the N DC coupling units, where the total first grid-connected power value is the sum of the first grid-connected power values of the N DC coupling units, wherein determining The first grid-connected power value of each of the N DC coupling units may be similar to the process described in the method 100, and details are not described herein again.
- the total first grid-connected power value p energy_to_grid is:
- P bus_energy_to_grid_j is the first grid-connected power value of the jth DC coupling unit in the N DC coupling units.
- the overall controller determines whether the total first grid-connected power value of the N DC coupling units meets the demand of the grid.
- the general controller determines that the total first grid-connected power value of the N DC coupling units does not meet the grid demand.
- the power connected to the grid can be allocated to the energy storage units in the N DC coupling units, so as to meet the demand of the grid.
- the overall controller determines that the total first grid-connected power value of the N DC coupling units does not meet the demand of the grid, S213, the overall controller determines the energy storage grid-connected demand power required by the grid according to the total first grid-connected power value.
- the grid-connected demand power p 2 of the energy storage is the difference between the total grid demand power p 1 minus the total first grid-connected power value p energy_to_grid , that is:
- step S220 the manner of acquiring the second amplitude limit value in step S220 will be described with reference to the following steps S221 to S223.
- the overall controller acquires the second power value of each of the N DC coupling units.
- the second power value is the maximum discharge power of the inverter unit in each DC coupling unit.
- the method for the overall controller to obtain the second power value may be similar to S122 in the method 120, and for simplicity, details are not repeated here.
- the overall controller acquires the third power value of each of the N DC coupling units.
- the third power value is the maximum discharge power of the energy storage unit in each DC coupling unit.
- the overall controller may select from the at least one energy storage controller The maximum discharge power of the corresponding energy storage battery can be obtained, and the maximum discharge power of each energy storage controller can also be obtained.
- the overall controller determines the third power value of each DC coupling unit according to the maximum discharge power of the at least one energy storage battery and the maximum discharge power of the at least one energy storage controller, wherein the jth of the N DC coupling units
- the third power value p bus_max_bat_discharge_j of the DC coupling units is:
- p bat_max_discharge_ji is the maximum discharge power of the i-th energy storage battery in the j-th DC coupling unit
- p dcdc_max_discharge_ji is the maximum discharge power of the i-th energy storage controller in the j-th DC coupling unit.
- the number is the charging direction of the energy storage unit
- both p bat_max_discharge_ji and p dcdc_max_discharge_ji are negative values.
- the final maximum discharge power of the energy storage battery and the corresponding energy storage controller is the maximum value of the maximum discharge power of the two, and the maximum discharge power of the energy storage unit in the DC coupling unit is all the storage power in the DC coupling unit.
- one energy storage controller can control one or more energy storage batteries, which is not limited in this application.
- the overall controller determines the second amplitude limiting value of each DC coupling unit according to the second power value and the third power value of each DC coupling unit in the N DC coupling units.
- the overall controller determines the minimum value of the following items as the second limit value of each DC coupling unit: the second power value of each DC coupling unit, the The third power value.
- the second limit value p lim_2_j of the jth DC coupling unit in the N DC coupling units is:
- p lim_2_j min(p bus_max_bat_discharge_j ,p bus_max_pcs_discharge_j ) (10)
- the actual discharge of the energy storage unit in the DC coupling unit needs to be limited by the inverter unit, so as to prevent the energy storage battery, the energy storage controller or the inverter from running in excess, resulting in a decrease in the reliability of the power system.
- the general controller may assign the minimum value of the following items Determined as the second limit value of each DC coupling unit: the second power value of each DC coupling unit, the residual discharge power value of each DC coupling unit, wherein the residual discharge power value is the first power value of each DC coupling unit.
- the second power value minus the first grid-connected power value.
- the second limit value p lim_2_j of the jth DC coupling unit in the N DC coupling units may be:
- p lim_2_j min(p bus_max_bat_discharge_j ,p bus_max_pcs_discharge_j -p bus_energy_to_grid_j ) (11)
- the inverter unit since the inverter unit has already endured the discharge power of the energy unit, the power input to the grid that has been allocated to the energy unit needs to be considered when allocating the power input to the grid to the energy storage unit.
- step S230 in FIG. 7 the manner of acquiring the second network access power value in step S230 in FIG. 7 is described with reference to FIG. 8 , which shows a schematic flowchart of acquiring the second network access power value.
- the overall controller performs a second iterative calculation according to the grid-connected demand power of the energy storage and the second limit value of the N DC coupling units to determine the second grid-connected power value of the N DC coupling units.
- the total controller acquires the first energy values of the N DC coupling units.
- the first energy value is the electric energy currently stored by the energy storage unit in each of the N DC coupling units.
- the energy storage unit in each DC coupling unit includes at least one energy storage battery, and the general controller may obtain the current stored electrical energy.
- the overall controller determines the first energy value of each DC coupling unit in the N DC coupling units according to the electric energy currently stored by each energy storage battery, wherein the first energy value SOE bus_j of the jth DC coupling unit is:
- SOE ji is the electric energy currently stored by the i-th energy storage battery in the j-th DC coupling unit.
- the energy storage unit in one DC coupling unit may include multiple energy storage batteries, and the first energy value of the DC coupling unit is the sum of the electric energy currently stored by all the energy storage batteries in the DC coupling unit.
- the total controller calculates the initial second candidate grid-connected power values of the N DC coupling units.
- the overall controller determines the initial second candidate power value of each DC coupling unit in the N DC coupling units according to the following formula, wherein the initial second candidate power value of the jth DC coupling unit Value is:
- P bus_bat_to_grid_j represents the initial second candidate grid-connected power value of the j-th DC coupling unit among the N DC coupling units
- P2 represents the grid-connected power demand of energy storage
- the overall controller determines M fourth DC coupling units among the N DC coupling units.
- the initial second candidate network access power value of the fourth DC coupling unit is greater than or equal to its corresponding second amplitude limit value, and M is a positive integer.
- the fourth DC coupling unit may be understood as a DC coupling unit in the second amplitude limiting state after this calculation.
- the overall controller makes a determination according to the M fourth DC coupling units.
- the overall controller determines the second grid access power value of the N DC coupling units to its corresponding initial second candidate grid access power value, and ends the second iterative calculation.
- the general controller can assign its corresponding energy storage unit to the N DC coupling units.
- the initial second candidate grid-connected power value enters the grid.
- the overall controller determines that the second grid-connected power value of the M fourth DC coupling units is its corresponding second amplitude limit value, and ends the second iterative calculation.
- the N DC coupling units are all in the second amplitude limiting state, and the overall controller allocates its corresponding second amplitude limit to the energy storage unit among the N DC coupling units.
- the limit value enters the grid.
- the overall controller determines that the second grid-connected power value of the M fourth DC coupling units is its corresponding second amplitude limit value.
- the overall controller first allocates the second grid-connected power value to the M fourth DC coupling units, and then executes S2308.
- the M 1 third DC coupling units are DC coupling units to which the second grid-connected power value has not been assigned in the previous second iterative calculation, and M 1 is a positive integer and M 1 ⁇ N.
- the third DC coupling unit can also be understood as the second candidate network access power value calculated in the previous second iterative calculation is smaller than the corresponding second amplitude limit value.
- the master controller determines the reference energy storage grid connection demand power.
- the total controller determines the reference energy storage grid-connected demand power according to the following formula:
- p pref_2 is the reference energy storage grid-connected demand power
- p bus_bat_to_grid_j is the second grid-connected power value of the jth DC-coupling unit in the DC-coupling units to which the second grid-connected power value has been assigned.
- S2310 The overall controller calculates the second candidate grid-connected power values of the M 1 third DC coupling units.
- the overall controller determines the second candidate grid-connected power values of the M 1 third DC coupling units according to the following formula:
- p bus_bat_to_grid_j represents the second candidate grid connection power value of the jth third DC coupling unit in the M 1 third DC coupling units
- p pref_2 represents the reference energy storage grid connection demand power
- the reference energy storage grid connection demand power is the energy storage grid connection.
- SOE bus_j represents the jth third DC coupling unit among the M 1 third DC coupling units
- the first energy value of , It represents the sum of the first energy values of M 1 third DC coupling units, 1 ⁇ j ⁇ M 1 .
- the overall controller determines M 2 fourth DC coupling units in M 1 third DC coupling units.
- the second candidate network access power value obtained by the M 2 fourth DC coupling units calculated in S2310 is greater than or equal to the corresponding second amplitude limit value, and M 2 is a positive integer.
- S2312 The overall controller determines the second grid-connected power value of the M 2 fourth DC coupling units.
- the M 2 fourth DC coupling units are in the second amplitude limiting state, that is, the overall controller determines to assign their corresponding second amplitude limiting values to the power grid for the M 2 fourth DC coupling units.
- the overall controller makes a determination according to the M 1 third DC coupling units and the M 2 fourth DC coupling units.
- the overall controller determines to end the multiple rounds of second iterative calculation.
- the M 1 third DC coupling units that have not been allocated before are all allocated in S2312 with their corresponding second amplitude limiting values as the second grid-connected power values.
- the overall controller determines the second grid-connected power value of the M 1 third DC coupling units, and ends the multiple rounds of second iterative calculation.
- the second grid access power value of the M 1 third DC coupling units is the corresponding second candidate grid access power value.
- the general controller in the power system can obtain the maximum discharge power that the energy storage unit in the DC coupling unit can currently provide to the grid, that is, the second limit value, and the general controller can obtain the second limit value according to the second limit value.
- the second grid-connected power value is allocated to each DC coupling unit for the energy storage grid-connected power, which can prevent the reliability of the power system operation from decreasing due to the power devices in the power system exceeding the limit, thereby improving the reliability of the power system operation.
- the energy storage units in the power system can be discharged in a balanced manner, improving the life cycle of the power devices in the energy storage units.
- Fig. 9 is a schematic flowchart of a method 300 for allocating first inverter power to an inverter unit provided by an embodiment of the present application.
- the method 300 can be applied to a power system including N DC coupling units, N DC buses, and an overall controller.
- the total controller obtains the discharge demand power of the N DC coupling units.
- the discharge demand power is used to indicate the power allocated for the energy unit in each DC coupling unit to charge the energy storage units of the N DC coupling units.
- the total controller obtains the charging demand power of the N DC coupling units.
- the charging demand power is used to indicate the power obtained from the energy units of the N DC coupling units allocated to the energy storage unit in each DC coupling unit.
- S330 The overall controller determines the first inverter power value of each DC coupling unit according to the discharge demand power of the N DC coupling units and the charging demand power of the N DC coupling units.
- the first inverter power value is used to indicate the power of the inverter unit in each DC coupling unit to provide electrical energy to the grid, or the first inverter power value is used to indicate the inverter unit in each DC coupling unit. The power that draws electrical energy from the grid.
- the overall controller acquires the first power value of each of the N DC coupling units.
- the first power value is the maximum discharge power of the energy unit in each DC coupling unit.
- the manner in which the master controller obtains the first power value may be similar to the manner described in S121 in the method 100 , which is not repeated here for brevity.
- S312 The total controller acquires the total first grid-connected power value of the N DC coupling units.
- the total first grid-connected power value refers to the total power value of the input grid allocated for the energy units in the N DC coupling units.
- the overall controller may determine the first grid-connected power value of each of the N DC coupling units, where the total first grid-connected power value is the sum of the first grid-connected power values of the N DC coupling units, wherein determining The first grid-connected power value of each of the N DC coupling units may be similar to the process described in the method 100, and details are not described herein again.
- the total first grid-connected power value P energy_to_grid is:
- P bus_energy_to_grid_j is the first grid-connected power value of the jth DC coupling unit in the N DC coupling units.
- the overall controller acquires the third power value of each of the N DC coupling units.
- the third power value is the maximum discharge power of the energy storage unit in each DC coupling unit.
- the manner in which the overall controller obtains the third power value may be similar to the manner described in S222 in the method 200, and for brevity, details are not repeated here.
- the overall controller determines whether the total first grid-connected power value of the N DC coupling units meets the demand of the grid.
- the general controller determines that the total first grid-connected power value of the N DC coupling units satisfies the grid demand.
- the remaining power of the energy units in the N DC coupling units can be allocated to the energy storage units in the N DC coupling units for storage, thereby Improve the utilization rate of new energy electric energy.
- the overall controller may determine the total charging demand power according to the total first grid-connected power value.
- the total charging demand power is the total power obtained from the energy units in the N DC coupling units allocated to the energy storage units in the N DC coupling units.
- the overall controller determines the first charging capability value of the N DC coupling units.
- the first charging capability value is a capability value that the energy unit in the N DC coupling units can provide electrical energy to the energy storage unit.
- the overall controller can determine the first charging capability value p max_energy_to_bat_1 of the energy unit in the N DC coupling units to the energy storage unit according to the following formula:
- p bus_max_energy_j is the first power value of the jth DC coupling unit in the N DC coupling units, is the sum of the first power values of the N DC coupling units.
- the first charging capability value is the remaining dischargeable power value of the energy units in the N DC coupling units.
- the general controller obtains the maximum charging power of the energy storage unit in each of the N DC coupling units.
- the overall controller may select from the at least one energy storage controller Obtain the maximum charging power of the corresponding energy storage battery, and also obtain the maximum charging power of each energy storage controller.
- the overall controller determines the maximum charging power of the energy storage unit in each DC coupling unit according to the maximum charging power of the at least one energy storage battery and the maximum charging power of the at least one energy storage controller, wherein, among the N DC coupling units
- the maximum charging power P bus_max_bat_charge_j of the energy storage unit in the jth DC coupling unit is:
- p bat_max_charge_j ⁇ min(p bat_max_charge_ji ,p dcdc_max_charge_ji ) (18)
- P bat_max_charge_ji is the maximum charging power of the i-th energy storage battery in the j-th DC coupling unit
- P dcdc_max_charge_ji is the maximum charging power of the i-th energy storage controller in the j-th DC coupling unit.
- the final maximum charging power of the energy storage battery and the corresponding energy storage controller is the minimum value of the maximum charging power of the energy storage battery and the corresponding energy storage controller
- the maximum charging power of the energy storage unit in the DC coupling unit is the sum of the final maximum charging power of all the energy storage batteries in the DC coupling unit and the corresponding energy storage controller.
- one energy storage controller can control one or more energy storage batteries, which is not limited in this application.
- the overall controller determines the second charging capability value of the N DC coupling units.
- the second charging capability value is a capability value of electrical energy acceptable to the energy storage unit in the N DC coupling units.
- the overall controller may obtain the second charging capacity value p max_bat_charge according to the following formula:
- the second charging capability value of the N DC coupling units is the sum of the maximum charging power values of the energy storage units in each of the N DC coupling units.
- the total controller obtains the total charging demand power.
- the total charging demand power is the total power obtained from the energy units in the N DC coupling units allocated to the energy storage units in the N DC coupling units;
- the total controller may determine the total charging demand power according to the following formula:
- p max_energy_to_bat min(p max_bat_charge , p max_energy_to_bat_1 ) (20)
- the overall controller may determine the minimum value of the first charging capacity value and the second charging capacity value as the total charging demand power.
- the general controller acquires the discharge demand power of each of the N DC coupling units.
- the overall controller may determine the discharge demand power of each of the N DC coupling units according to the following formula, where the discharge demand power p bus_energy_to_bat_j of the jth DC coupling unit is:
- the discharge demand power of each DC coupling unit in the N DC coupling units can be based on the first power value of each DC coupling unit, that is, the maximum discharge power value of the energy unit in the DC coupling unit accounts for the N DC coupling units.
- FIG. 10 shows a schematic flow of obtaining the charging demand power picture.
- the overall controller may perform a third iterative calculation to determine the charging demand power of each of the N DC coupling units.
- the total controller obtains the third amplitude limiting value of the N DC coupling units.
- the third amplitude limit value is used to indicate the maximum charging power that can be provided by the energy storage unit in each of the N DC coupling units.
- the third amplitude limit value of each DC coupling unit may be the maximum charging power of each energy storage unit.
- the overall controller acquires the second energy value of each of the N DC coupling units.
- the second energy value is the difference between the total amount of storable electric energy value of the energy storage units in each DC coupling unit and the stored electric energy value.
- the overall controller can obtain the total amount of electric energy that can be provided by the energy storage unit in each DC coupling unit from the energy storage unit, or can preconfigure the energy storage unit in each DC coupling unit in the overall controller. The total amount of electrical energy available.
- the stored electric energy value of the energy storage unit in each DC coupling unit may be understood as the first energy value in the method 200, that is, the energy storage unit in each DC coupling unit of the N DC coupling units The current stored electrical energy. Therefore, the acquisition method may be similar to the acquisition method of step S2301 in the method 200 , which is not repeated here for brevity.
- the total controller calculates the initial candidate charging demand power of the N DC coupling units.
- the overall controller determines the initial candidate charging demand power of each of the N DC coupling units according to the following formula, where the initial candidate charging demand power of the jth DC coupling unit is :
- p bus_bat_charge_j represents the initial candidate charging demand power of the jth DC coupling unit in the N DC coupling units
- SOE bus_able_j represents the second energy value of the jth DC coupling unit in the N DC coupling units, is the sum of the second energy values of the N DC coupling units, 1 ⁇ j ⁇ N.
- the overall controller determines T sixth DC coupling units among the N DC coupling units.
- the initial candidate charging demand power of the sixth DC coupling unit is greater than or equal to its corresponding third amplitude limit value, and T is a positive integer.
- the sixth DC coupling unit may be understood as a DC coupling unit in the third amplitude limiting state after the calculation.
- the overall controller makes a determination according to the T sixth DC coupling units.
- the overall controller determines that the charging demand power of the N DC coupling units is its corresponding initial candidate charging demand power, and ends the third iterative calculation.
- the total controller can determine that the charging demand power of the N DC coupling units is the corresponding power of the N DC coupling units. Initial candidate charging demand power.
- the overall controller determines that the charging demand power of the T sixth DC coupling units is its corresponding third limit value, and ends the third iterative calculation.
- the N DC coupling units are all in the third amplitude limiting state, and the overall controller can determine that the charging demand power of the N DC coupling units is its corresponding No. Three clipping values.
- the overall controller determines that the charging demand power of the T sixth DC coupling units is its corresponding third limit value.
- the overall controller first allocates the charging demand power to the T sixth DC coupling units, and then executes S3209.
- the overall controller determines T 1 fifth DC coupling units.
- the T 1 fifth DC coupling units are DC coupling units to which charging demand power is not allocated in the previous third iterative calculation, and T 1 is a positive integer and T 1 ⁇ N.
- the fifth DC coupling unit can also be understood as the candidate charging demand power calculated and obtained in the previous third iterative calculation is smaller than the corresponding third amplitude limit value.
- the total controller determines the reference total charging demand power.
- the total controller determines the reference total charging demand power according to the following formula:
- p pref_3 is the reference total charging demand power, is the sum of the charging demand power of the DC coupling units to which the charging demand power has been allocated
- p bus_bat_charge_j is the charging demand power of the jth DC coupling unit in the DC coupling units to which the charging demand power has been allocated.
- the overall controller calculates the candidate charging demand power of the T 1 fifth DC coupling units.
- the total controller determines the candidate charging demand power of the T 1 fifth DC coupling units according to the following formula:
- p bus_bat_charge_j represents the selected charging demand power of the jth fifth DC coupling unit in the T 1 fifth DC coupling units
- p pref_3 represents the reference total charging demand power
- SOE bus_able_j represents the T 1 fifth DC the second energy value of the jth fifth DC coupling unit in the coupling unit, represents the sum of the second energy values of the T 1 fifth DC coupling units, 1 ⁇ j ⁇ T 1 .
- the overall controller determines T2 sixth DC coupling units in T1 fifth DC coupling units.
- the candidate charging demand power calculated and obtained by the T 2 sixth DC coupling units in S3211 is greater than or equal to the corresponding third amplitude limit value, and T 2 is a positive integer.
- the overall controller determines the charging demand power of the T 2 sixth DC coupling units.
- the T 2 sixth DC coupling units are in the third amplitude limiting state, that is, the overall controller determines that the charging demand power of the T 2 sixth DC coupling units is its corresponding third amplitude limiting value.
- the overall controller makes a determination according to the T1 fifth DC coupling units and the T2 sixth DC coupling units.
- the general controller determines to end the multiple rounds of third iterative calculation.
- the T 1 fifth DC coupling units that have not been assigned before are all assigned their corresponding third amplitude limiting values as the charging demand power in S3213 .
- the overall controller determines the charging demand power of the T 1 fifth DC coupling units, and ends the multiple rounds of third iterative calculation.
- the charging demand power of the T 1 fifth DC coupling units is the corresponding reference charging demand power.
- the total controller can determine the charging demand power of the N DC coupling units.
- step S330 in FIG. 9 the manner of obtaining the first inverter power value in step S330 in FIG. 9 will be described with reference to the following steps S3301 to S3309.
- the overall controller determines the exchange power of each DC coupling unit in the N DC coupling units.
- the exchange power is the discharge demand power of each of the N DC coupling units minus the corresponding charging demand power.
- the exchange power p bus_pcs_to_other_j of the jth DC coupling unit in the N DC coupling units is:
- p bus_pcs_to_other_j p bus_energy_to_bat_j -p bus_bat_charge_j (25)
- the overall controller inverts power according to the first candidate of the N DC coupling units.
- the power value of each DC coupling unit in the N DC coupling units is the sum of the exchange power of each DC coupling unit and the corresponding first grid-connected power value, and the first candidate inverter power value p bus_pcs_to_grid_j_1 of the jth DC coupling unit in the N DC coupling units is :
- p bus_pcs_to_grid_j_1 p bus_pcs_to_other_j +p bus_energy_to_grid_j (26)
- the inverter unit in the DC coupling unit needs to bear the power value output by the energy unit in the same DC coupling unit. Therefore, the inverter power actually carried by the inverter unit is the same as the energy in the same DC coupling unit.
- the power input to the grid by the unit, the power charged by the energy unit to the energy storage unit, and the power charged by the energy unit in the same DC coupling unit are related.
- S3303 The overall controller acquires the second power value of each DC coupling unit in the N DC coupling units.
- the second power value is the maximum discharge power of the inverter unit in each DC coupling unit.
- the method for the overall controller to acquire the second power value may be similar to S122 in the method 120 .
- the master controller determines the discharge adjustment demand value.
- the discharge adjustment demand value is less than the first candidate inverter power value of the DC coupling unit in which the first candidate inverter power value is greater than 0 and the first candidate inverter power value is greater than the corresponding second power value among the N DC coupling units. to the sum of the differences of the corresponding second power values.
- the discharge adjustment demand value Delta_pos_sum is:
- the first candidate inverter power value of the DC coupling unit is greater than 0, it can be understood that the inverter unit of the DC coupling unit is in a discharge state, and it can be considered whether the first candidate inverter power value of the DC coupling unit exceeds 0. If the maximum discharge power value of the inverter unit is exceeded, it indicates that the DC coupling unit cannot withstand the first candidate inverter power, the inverter unit is limited, and the discharge adjustment demand value is the value of the N DC coupling units. The DC coupling unit of the inverter unit being clipped exceeds the sum of the second power value.
- the overall controller determines the charging adjustment demand value.
- the charging adjustment demand value is less than the fourth power value of the DC coupling unit for which the first candidate inverter power value of the N DC coupling units is less than 0, and the first candidate inverter power value is less than the corresponding fourth power value.
- the fourth power value is the maximum charging power of the inverter unit in each DC coupling unit.
- the overall controller obtains the maximum charging power of each inverter, wherein the jth The maximum charging power of the ith inverter in the inverter unit in the DC coupling units is p pcs_max_charge_ji .
- the maximum charging power of the inverter unit in each DC coupling unit is the sum of the maximum charging powers of all inverters in the inverter unit in each DC coupling unit.
- the charging adjustment demand value Delta_neg_sum is:
- the negative sign of the first candidate inverter power value and the fourth power value indicates that the power direction is the charging direction.
- the charging direction can be understood as the direction from the power grid through the inverter unit to the energy storage unit, and its absolute value represents the magnitude of the power value. .
- the inverter unit of the DC coupling unit is in a charging state, and the absolute value of the first candidate inverter power value of the DC coupling unit can be considered. Whether the value exceeds the maximum charging power value of the inverter unit, if so, it indicates that the DC coupling unit cannot withstand the first candidate inverter power, the inverter unit is limited, and the discharge adjustment demand value is N DC
- the DC coupling unit in which the inverter unit is clipped in the coupling unit exceeds the sum of the fourth power value.
- the master controller determines to adjust the required power.
- the adjusted demand power is the absolute value of the difference between the discharge adjustment demand value and the charge adjustment demand value.
- the adjusted demand power Delta is:
- the total controller acquires the adjustment ratio value of each DC coupling unit in the N DC coupling units.
- the adjustment ratio value is the ratio of the exchange power value of each DC coupling unit to the sum of the exchange power values of the DC coupling units whose exchange power value is greater than 0.
- the adjustment ratio of the jth DC coupling unit in the N DC coupling units is:
- the overall controller determines the second candidate inverter power value of each of the N DC coupling units.
- the second candidate inverter power value of the DC coupling unit whose first candidate inverter power value is greater than 0 is the minimum value among the corresponding first candidate inverter power value and the corresponding second power value
- the first candidate inverter power value is the minimum value.
- the second candidate inverter power value of the DC coupling unit whose power value is less than 0 is the maximum value among the corresponding first candidate inverter power value and the corresponding fourth power value.
- p bus_pcs_to_grid_j_2 min(p bus_pcs_to_grid_j_1 , p bus_max_pcs_discharge_j ) (32)
- p bus_pcs_to_grid_j_2 max(p bus_pcs_to_grid_j_1 ,p bus_max_pcs_charge_j ) (33)
- p bus_pcs_to_grid_j_2 is the second candidate inverter power value of the jth DC coupling unit in the N DC coupling units
- p bus_pcs_to_grid_j_1 is the first candidate inverter power value of the jth DC coupling unit in the N DC coupling units
- p bus_max_pcs_discharge_j is the second power value of the jth DC coupling unit among the N DC coupling units
- p bus_max_pcs_charge_j is the fourth power value of the jth DC coupling unit among the N DC coupling units.
- the first inverter power value of the DC coupling unit with p bus_pcs_to_other_j ⁇ 0 is:
- the first inverter power value of the DC coupling unit with p bus_pcs_to_other_j >0 is:
- the first inverter power value of the DC coupling unit with p bus_pcs_to_other_j ⁇ 0 is:
- the first inverter power value of the DC coupling unit with p bus_pcs_to_other_j >0 is:
- the first inverter may be allocated according to the ratio of the maximum discharge power of each inverter to the second power value power value, or assign the first inverter power value according to the ratio of the maximum charging power of each inverter to the fourth power value.
- p pcs_to_grid_ji represents the inverter power of the i-th inverter in the inverter unit in the j-th DC coupling unit
- p pcs_max_discharge_ji represents the i-th inverter in the inverter unit in the j-th DC coupling unit.
- p pcs_max_charge_ji represents the maximum charging power of the i-th inverter in the inverter unit in the j-th DC coupling unit.
- the electric energy generated by the energy unit of the DC coupling unit can be supplied to the DC coupling unit and/or other DC coupling units.
- the energy storage unit is charged, thereby reducing the power waste of the energy unit.
- FIG. 11 is a method 400 of allocating absorbed power to an energy storage unit
- FIG. 13 is a method 500 of allocating a first inverter power to an inverter unit.
- the method 400 and the method 500 can be used independently in the power system, or can be combined and used in the power system.
- the method 400 is used to allocate the absorbed power to the energy storage units of the DC-coupled system. If the energy storage units can meet the dispatching requirements of the power grid, the method 500 can be used for the DC-coupled system.
- the inverter unit distributes the first inverter power, so that the remaining capacity of the energy storage unit can be used to store the electrical energy emitted by the energy unit.
- FIG. 11 is a schematic flowchart of a method 400 for allocating absorbed power to an energy storage unit according to an embodiment of the present application.
- the method 400 can be applied to a power system that includes N DC coupling units, N DC buses, and an overall controller.
- the master controller acquires the power required to be absorbed by the power grid.
- the absorption demand power is the power that the energy storage unit in the N DC coupling units needs to absorb from the power grid.
- S420 The overall controller acquires the fourth amplitude limiting value of the N DC coupling units.
- the fourth limit value is used to indicate the maximum charging power that each DC coupling unit can provide.
- S430 The overall controller determines the absorbed power value of the N DC coupling units according to the absorbed demand power and the fourth amplitude limit value of the N DC coupling units.
- the absorbed power value refers to the power value absorbed from the power grid allocated to the energy unit in each DC coupling unit, wherein at least one DC coupling unit in the N DC coupling units is in a fourth amplitude limiting state, and the The fourth limit state means that the absorbed power value allocated to the DC coupling unit is equal to the corresponding fourth limit value.
- step S420 in FIG. 11 the manner of obtaining the fourth amplitude limit value in step S420 in FIG. 11 will be described with reference to the following steps S421 to S423.
- the overall controller acquires the absolute value of the fourth power value of each of the N DC coupling units.
- the fourth power value is the maximum charging power of the inverter unit in each DC coupling unit.
- the overall controller obtains the maximum charging power of each inverter, wherein the jth The maximum charging power of the ith inverter in the inverter unit in the DC coupling units is P pcs_max_charge_ji .
- the overall controller determines the maximum charging power of the inverter unit in each of the N DC coupling units according to the maximum charging power of the at least one inverter, wherein the maximum charging power of the inverter unit in the jth DC coupling unit is The power, that is, the fourth power value P bus_max_pcs_charge_j is:
- the maximum charging power of the inverter unit in each DC coupling unit is the sum of the maximum charging powers of all inverters in the inverter unit in each DC coupling unit.
- the overall controller acquires the fifth power value of each of the N DC coupling units.
- the fifth power value is the maximum charging power of the energy storage unit in each DC coupling unit.
- the overall controller may select from the at least one energy storage controller Obtain the maximum charging power of the corresponding energy storage battery, and also obtain the maximum charging power of each energy storage controller.
- the overall controller determines the fifth power value of each DC coupling unit according to the maximum charging power of the at least one energy storage battery and the maximum charging power of the at least one energy storage controller, wherein the jth of the N DC coupling units
- the fifth power value P bus_max_bat_charge_j of the DC coupling units is:
- P bus_max_bat_charge_j ⁇ min(P bat_max_charge_ji ,P dcdc_max_charge_ji ) (41)
- P bat_max_charge_ji is the maximum charging power of the i-th energy storage battery in the j-th DC coupling unit
- P dcdc_max_charge_ji is the maximum charging power of the i-th energy storage controller in the j-th DC coupling unit.
- the final maximum charging power of the energy storage battery and the corresponding energy storage controller is the minimum value of the maximum charging power of the two, and the maximum charging power of the energy storage unit in the DC coupling unit is all the storage power in the DC coupling unit.
- one energy storage controller can control one or more energy storage batteries, which is not limited in this application.
- the total controller obtains the fourth amplitude limiting value of the N DC coupling units.
- the overall controller determines the minimum value of the following as the fourth clipping value for each DC-coupling unit: the absolute value of the fourth power value for each DC-coupling unit, the fifth power value for each DC-coupling unit .
- the fourth limit value P lim_4_j of the jth DC coupling unit in the N DC coupling units is:
- P lim_4_j min(P bus_max_bat_charge_j ,P bus_max_pcs_charge_j ) (42)
- the actual charging power of the energy storage unit in the DC coupling unit needs to be limited by the inverter unit, so as to avoid excessive operation of the energy storage battery, the energy storage controller or the inverter, which will reduce the reliability of the power system.
- step S430 in FIG. 11 the manner of acquiring the absorbed power value in step S430 in FIG. 11 is described with reference to FIG. 12 , which shows a schematic flowchart of acquiring the absorbed power value.
- the overall controller acquires the second energy values of the N DC coupling units.
- the second energy value is the difference between the total amount of storable electric energy value of the energy storage units in each DC coupling unit and the stored electric energy value.
- the first energy value is the electric energy currently stored by the energy storage unit in each of the N DC coupling units.
- the overall controller may obtain the stored electric energy value of the N DC coupling units, and define the electric energy stored in each of the N DC coupling units, or the currently stored electric energy is the first energy value.
- the overall controller can acquire the electric energy currently stored by each energy storage battery in the energy storage unit in each DC coupling unit.
- the overall controller determines the first energy value of each DC coupling unit in the N DC coupling units according to the electric energy currently stored by each energy storage battery, wherein the first energy value SOE bus_j of the jth DC coupling unit is:
- SOE ji is the electric energy currently stored by the i-th energy storage battery in the j-th DC coupling unit.
- the energy storage unit in one DC coupling unit may include multiple energy storage batteries, and the first energy value of the DC coupling unit is the sum of the electric energy currently stored by all the energy storage batteries in the DC coupling unit.
- the total amount of electric energy that can be provided by the energy storage unit in each DC coupling unit may be obtained from the energy storage unit, or the available energy value of the energy storage unit in each DC coupling unit may be preconfigured in the overall controller. The total amount of electrical energy provided.
- the second energy value SOE bus_able_j of the jth DC coupling unit in the N DC coupling units is:
- SOE bus_able_j SOE bus_full_j - SOE bus_j (44)
- SOE bus_full_j is the total amount of electric energy that can be stored in the jth DC coupling unit
- SOE bus_j is the stored electric energy value of the jth DC coupling unit.
- the total controller calculates the initial candidate absorbed power values of the N DC coupling units.
- the total controller determines the initial candidate absorbed power value of each of the N DC coupling units according to the following formula, wherein the initial candidate absorbed power value of the jth DC coupling unit is :
- p absorb is the required power to absorb
- p bus_bat_from_grid_j represents the initial candidate absorbed power value of the jth DC coupling unit among the N DC coupling units
- SOE bus_able_j represents the second energy of the jth DC coupling unit among the N DC coupling units value, is the sum of the second energy values of the N DC coupling units, 1 ⁇ j ⁇ N.
- the overall controller determines Q eighth DC coupling units among the N DC coupling units.
- the initial candidate absorbed power value of the eighth DC coupling unit is greater than or equal to its corresponding fourth amplitude limit value, and Q is a positive integer.
- the eighth DC coupling unit can be understood as the DC coupling unit in the fourth amplitude limiting state after this calculation.
- the overall controller makes a determination according to the Q eighth DC coupling units.
- the total controller determines the absorbed power value of the N DC coupling units to its corresponding initial candidate absorbed power value, and ends the fourth iterative calculation.
- the total controller can determine that the absorbed power value of the N DC coupling units corresponds to Initial candidate absorbed power value.
- the total controller determines that the absorbed power value of the Q eighth DC coupling units is the corresponding fourth amplitude limit value, and ends the fourth iterative calculation.
- the N DC coupling units are all in the fourth amplitude limiting state, and the total controller can determine that the absorbed power value of the N DC coupling units is the corresponding Four clipping values.
- the overall controller determines that the absorbed power value of the Q eighth DC coupling units is its corresponding fourth amplitude limit value.
- the overall controller first allocates the absorbed power value to the Q eighth DC coupling units, and then executes S4308.
- the Q 1 seventh DC-coupling units are DC-coupling units that have not been assigned an absorbed power value in the previous fourth iterative calculation, and Q 1 is a positive integer and Q 1 ⁇ N.
- the seventh DC coupling unit can also be understood as the candidate absorbed power value calculated in the previous fourth iterative calculation is smaller than the corresponding fourth amplitude limit value.
- the master controller determines the reference absorption demand power value.
- the overall controller determines the reference absorbed demand power value according to the following formula:
- p pref_absorb is the reference absorption demand power value, is the sum of the absorbed power values of the DC coupling units to which the absorbed power value has been assigned, and p bus_bat_from_grid_j is the absorbed power value of the jth DC coupling unit in the DC coupling units to which the absorbed power value has been assigned.
- the overall controller calculates the candidate absorbed power values of the Q 1 seventh DC coupling units.
- the total controller determines the candidate absorbed power values of the Q 1 seventh DC coupling units according to the following formula:
- p bus_bat_from_grid_j represents the first candidate absorbed power value of the jth seventh DC coupling unit in the Q1 seventh DC coupling units
- pref_absorb represents the reference absorption demand power value
- SOE bus_able_j represents the Q1th the second energy value of the jth seventh DC coupling unit in the seven DC coupling units, represents the sum of the second energy values of the Q 1 seventh DC coupling units, 1 ⁇ j ⁇ Q 1 .
- the overall controller determines Q 2 eighth DC coupling units in Q 1 seventh DC coupling units.
- the candidate absorbed power value calculated by the Q 2 eighth DC coupling units in S4310 is greater than or equal to the corresponding fourth amplitude limit value, and Q 2 is a positive integer.
- the overall controller determines the absorbed power value of the Q 2 eighth DC coupling units.
- the Q 2 eighth DC coupling units are in the fourth amplitude limiting state, that is, the overall controller determines that the absorbed power value of the Q 2 eighth DC coupling units is the corresponding fourth amplitude limiting value.
- the overall controller makes a determination according to the Q 1 seventh DC coupling unit and the Q 2 eighth DC coupling units.
- the overall controller determines to end the multiple rounds of fourth iterative calculation.
- the Q 1 seventh DC coupling units that have not been assigned before are all assigned their corresponding fourth amplitude limiting values as absorbed power values in S4312 .
- the overall controller determines the absorbed power value of the Q 1 seventh DC coupling units, and ends the multiple rounds of fourth iterative calculation.
- the absorbed power values of the Q 1 seventh DC coupling units are corresponding candidate absorbed power values.
- the total controller can determine the absorbed power value of the N DC coupling units.
- the general controller in the power system can obtain the maximum charging power that each DC coupling unit can provide, that is, the maximum charging power that the energy storage unit in the DC coupling unit can absorb from the grid currently, that is, the first charging power.
- the total controller assigns the absorbed power value to each DC coupling unit according to the fourth limit value to the absorbed demand power value, which can avoid the reliability of the power system operation caused by the power devices in the power system exceeding the limit. decrease, thereby improving the reliability of power system operation.
- FIG. 13 is a schematic flowchart of a method 500 for allocating first inverter power to an inverter unit according to an embodiment of the present application.
- the method 500 can be applied to a power system including N DC coupling units, N DC buses, and an overall controller.
- the total controller obtains the discharge demand power of the N DC coupling units.
- the discharge demand power is used to indicate the power allocated for the energy unit in each DC coupling unit to charge the energy storage units of the N DC coupling units.
- the total controller obtains the charging demand power of the N DC coupling units.
- the charging demand power is used to indicate the power obtained from the energy units of the N DC coupling units allocated to the energy storage unit in each DC coupling unit.
- S530 The overall controller determines the first inverter power value of each DC coupling unit according to the discharge demand power of the N DC coupling units and the charging demand power of the N DC coupling units.
- the first inverter power value is used to indicate the power of the inverter unit in each DC coupling unit to provide electrical energy to the grid, or the first inverter power value is used to indicate the inverter unit in each DC coupling unit. The power that draws electrical energy from the grid.
- step S510 in FIG. 13 the manner of obtaining the discharge demand power in step S510 in FIG. 13 will be described with reference to the following steps S511 to S518.
- the overall controller acquires the first power value of each of the N DC coupling units.
- the first power value is the maximum discharge power of the energy unit in each DC coupling unit.
- the master controller may be obtained from the at least one photovoltaic master controller The maximum discharge power of the at least one photovoltaic cell.
- the MPPT controller can provide the master master controller with the maximum discharge power of its corresponding photovoltaic cell, wherein the ith photovoltaic cell in the energy unit in the jth DC coupling unit
- the maximum discharge power of the battery is P max_energy_ji .
- the maximum discharge power value provided by the MPPT controller to the total controller may be the estimated value of the discharge power of the corresponding photovoltaic cell by the MPPT controller, If the photovoltaic cell corresponding to the MPPT controller is in a derating state, the maximum discharge power value provided by the MPPT controller to the total controller may be the maximum discharge power after derating.
- the overall controller obtains the maximum discharge power of the energy unit in each of the N DC coupling units according to the maximum discharge power of the at least one photovoltaic cell, wherein the maximum discharge power P bus_max_energy_j of the energy unit in the jth DC coupling unit for:
- the maximum discharge power of the energy unit in each DC coupling unit is the sum of the maximum discharge power of the photovoltaic cells provided by all photovoltaic controllers in the energy unit in each DC coupling unit.
- the total controller acquires the total absorbed power value of the N DC coupling units.
- the absorbed power value refers to the value of power absorbed from the grid allocated to the energy unit in each DC coupling unit.
- the total controller may determine the absorbed power value of each of the N DC coupling units, where the total absorbed power value is the sum of the absorbed power values of the N DC coupling units, wherein the N DC coupling units are determined
- the absorbed power value of each DC coupling unit may be similar to the process described in the method 400 , which is not repeated here for brevity.
- the total absorbed power value p bat_from_grid is:
- p bus_bat_from_grid_j is the absorbed power value of the jth DC coupling unit in the N DC coupling units.
- the overall controller determines whether the total absorbed power value of the N DC coupling units meets the demand of the power grid.
- the overall controller determines that the total absorbed power value of the N DC coupling units satisfies the demand of the grid.
- the general controller can allocate the power of the energy unit to the energy storage unit for storage, thereby improving the utilization rate of new energy electric energy.
- the total controller may determine the total charging demand power according to the total absorbed power value.
- the total charging demand power is the total power obtained from the energy units in the N DC coupling units allocated to the energy storage units in the N DC coupling units.
- the overall controller determines the first charging capability value of the N DC coupling units.
- the first charging capability value is a capability value that the energy unit in the N DC coupling units can provide electrical energy to the energy storage unit.
- the overall controller can determine the first charging capability value p max_energy_to_bat_1 of the energy unit in the N DC coupling units to the energy storage unit according to the following formula:
- p bus_max_energy_j is the first power value of the jth DC coupling unit in the N DC coupling units.
- the total controller obtains the maximum charging power of the energy storage unit in each of the N DC coupling units.
- the overall controller may select from the at least one energy storage controller Obtain the maximum charging power of the corresponding energy storage battery, and also obtain the maximum charging power of each energy storage controller.
- the overall controller determines the maximum charging power of the energy storage unit in each DC coupling unit according to the maximum charging power of the at least one energy storage battery and the maximum charging power of the at least one energy storage controller, wherein, among the N DC coupling units
- the maximum charging power P bus_max_bat_charge_j of the energy storage unit in the jth DC coupling unit is:
- P bat_max_charge_ji is the maximum charging power of the i-th energy storage battery in the j-th DC coupling unit
- P dcdc_max_charge_ji is the maximum charging power of the i-th energy storage controller in the j-th DC coupling unit.
- the final maximum charging power of the energy storage battery and the corresponding energy storage controller is the minimum value of the maximum charging power of the energy storage battery and the corresponding energy storage controller
- the maximum charging power of the energy storage unit in the DC coupling unit is the sum of the final maximum charging power of all the energy storage batteries in the DC coupling unit and the corresponding energy storage controller.
- one energy storage controller can control one or more energy storage batteries, which is not limited in this application.
- the overall controller determines the second charging capability value of the N DC coupling units.
- the second charging capability value is a capability value of electrical energy acceptable to the energy storage unit in the N DC coupling units.
- the overall controller may obtain the second charging capacity value p bus_bat_rest_charge according to the following formula:
- the second charging capability value of the N DC coupling units is the sum of the difference between the maximum charging power and the absorbed power value of the energy storage unit in each DC coupling unit in each DC coupling unit.
- the total controller obtains the total charging demand power.
- the total charging demand power is the total power obtained from the energy units in the N DC coupling units allocated to the energy storage units in the N DC coupling units;
- the total controller may determine the total charging demand power according to the following formula:
- p max_energy_to_bat min(p bus_bat_rest_charge , p max_energy_to_bat_1 ) (53)
- the overall controller may determine the minimum value of the first charging capacity value and the second charging capacity value as the total charging demand power.
- the general controller acquires the discharge demand power of each of the N DC coupling units.
- the overall controller may determine the discharge demand power of each of the N DC coupling units according to the following formula, where the discharge demand power of the jth DC coupling unit is:
- the discharge demand power of each DC coupling unit in the N DC coupling units can be based on the first power value of each DC coupling unit, that is, the maximum discharge power value of the energy unit in the DC coupling unit accounts for the N DC coupling units.
- step S520 in FIG. 13 the manner of obtaining the charging demand power in step S520 in FIG. 13 will be described with reference to the following steps S5201 to S5216.
- the overall controller may perform a third iterative calculation to determine the charging demand power of each of the N DC coupling units.
- the overall controller obtains the third amplitude limiting value of the N DC coupling units.
- the third amplitude limit value is used to indicate the maximum charging power that can be provided by the energy storage unit in each of the N DC coupling units.
- the third amplitude limit value of each DC coupling unit may be the maximum charging power that each energy storage unit can provide.
- the maximum charging power that the energy storage unit can provide is the maximum charging power of the DC coupling unit.
- the maximum charging power that the energy storage unit can provide is the difference between the corresponding maximum charging power and the corresponding absorbed power value.
- the charging power that can be allocated to the energy storage unit is limited by its own maximum charging power and the allocated charging power.
- the overall controller acquires the second energy value of each of the N DC coupling units.
- the second energy value is the difference between the total amount of storable electric energy value of the energy storage units in each DC coupling unit and the stored electric energy value.
- the overall controller can obtain the total amount of electric energy that can be provided by the energy storage unit in each DC coupling unit from the energy storage unit, or can preconfigure the energy storage unit in each DC coupling unit in the overall controller. The total amount of electrical energy available.
- the manner in which the master controller acquires the second energy value of each of the N DC coupling units may be similar to the manner in which the second energy value is acquired in step S4301 in the method 400 , which is not repeated here for brevity.
- the total controller calculates the initial candidate charging demand power of the N DC coupling units.
- the overall controller determines the initial candidate charging demand power of each of the N DC coupling units according to the following formula, where the initial candidate charging demand power of the jth DC coupling unit is :
- p bus_bat_charge_j represents the initial candidate charging demand power of the jth DC coupling unit in the N DC coupling units
- SOE bus_able_j represents the second energy value of the jth DC coupling unit in the N DC coupling units, is the sum of the second energy values of the N DC coupling units, 1 ⁇ j ⁇ N.
- the overall controller determines T sixth DC coupling units among the N DC coupling units.
- the initial candidate charging demand power of the sixth DC coupling unit is greater than or equal to its corresponding third amplitude limit value, and T is a positive integer.
- the sixth DC coupling unit may be understood as a DC coupling unit in the third amplitude limiting state after the calculation.
- the overall controller makes a determination according to the T sixth DC coupling units.
- the overall controller determines that the charging demand power of the N DC coupling units is its corresponding initial candidate charging demand power, and ends the third iterative calculation.
- the total controller can determine that the charging demand power of the N DC coupling units is the corresponding power of the N DC coupling units. Initial candidate charging demand power.
- the overall controller determines that the charging demand power of the T sixth DC coupling units is its corresponding third limit value, and ends the third iterative calculation.
- the N DC coupling units are all in the third amplitude limiting state, and the overall controller can determine that the charging demand power of the N DC coupling units is its corresponding No. Three clipping values.
- the overall controller determines that the charging demand power of the T sixth DC coupling units is its corresponding third limit value.
- the overall controller first allocates the charging demand power to the T sixth DC coupling units, and then executes S5209.
- the overall controller determines T1 fifth DC coupling units.
- the T 1 fifth DC coupling units are DC coupling units to which charging demand power is not allocated in the previous third iterative calculation, and T 1 is a positive integer and T 1 ⁇ N.
- the fifth DC coupling unit can also be understood as the candidate charging demand power calculated and obtained in the previous third iterative calculation is smaller than the corresponding third amplitude limit value.
- the total controller determines the reference total charging demand power.
- the total controller determines the reference total charging demand power according to the following formula:
- P ref_3 is the reference total charging demand power, is the sum of the charging demand power of the DC coupling units to which the charging demand power has been allocated, and p bus_bat_charge_j is the charging demand power of the jth DC coupling unit in the DC coupling units to which the charging demand power has been allocated.
- the overall controller calculates the candidate charging demand power of the T 1 fifth DC coupling units.
- the total controller determines the candidate charging demand power of the T 1 fifth DC coupling units according to the following formula:
- p bus_bat_charge_j represents the selected charging demand power of the jth fifth DC coupling unit among the T 1 fifth DC coupling units
- P pref_3 represents the reference total charging demand power
- SOE bus_able_j represents the T 1 fifth DC coupling unit the second energy value of the jth fifth DC coupling unit in the coupling unit, represents the sum of the second energy values of the T 1 fifth DC coupling units, 1 ⁇ j ⁇ T 1 .
- the overall controller determines T2 sixth DC coupling units in T1 fifth DC coupling units.
- the candidate charging demand power calculated and obtained by the T 2 sixth DC coupling units in S5211 is greater than or equal to the corresponding third amplitude limit value, and T 2 is a positive integer.
- the overall controller determines the charging demand power of the T 2 sixth DC coupling units.
- the T 2 sixth DC coupling units are in the third amplitude limiting state, that is, the overall controller determines that the charging demand power of the T 2 sixth DC coupling units is its corresponding third amplitude limiting value.
- the overall controller makes a determination according to the T1 fifth DC coupling units and the T2 sixth DC coupling units.
- the overall controller determines to end the multiple rounds of third iterative calculation.
- the T 1 fifth DC coupling units that have not been allocated before are all allocated their corresponding third amplitude limiting values as the charging demand power in S5213 .
- the overall controller determines the charging demand power of the T 1 fifth DC coupling units, and ends the multiple rounds of third iterative calculation.
- the charging demand power of the T 1 fifth DC coupling units is the corresponding reference charging demand power.
- the total controller can determine the charging demand power of the N DC coupling units.
- step S530 in FIG. 13 the manner of acquiring the first inverter power value in step S530 in FIG. 13 will be described with reference to the following steps S5301 to S5216.
- the overall controller determines the exchange power of each DC coupling unit in the N DC coupling units.
- the exchange power is the discharge demand power of each of the N DC coupling units minus the corresponding charging demand power.
- the exchange power p bus_pcs_to_other_j of the jth DC coupling unit in the N DC coupling units is:
- p bus_pcs_to_other_j p bus_energy_to_bat_j -p bus_bat_charge_j (57)
- the overall controller inverts power according to the first candidate of the N DC coupling units.
- the power of each DC coupling unit in the N DC coupling units is the difference between the exchange power of each DC coupling unit and the corresponding absorbed power value, and the first candidate inverter power value p bus_pcs_to_grid_j_1 of the jth DC coupling unit in the N DC coupling units is:
- p bus_pcs_to_grid_j_1 p bus_pcs_to_other_j -p bus_bat_from_grid_j (58)
- the inverter unit in the DC coupling unit needs to bear the power value absorbed by the energy storage unit in the same DC coupling unit. Therefore, the inverter power actually carried by the inverter unit is the same as the power value in the same DC coupling unit.
- the power value absorbed by the energy storage unit, the power charged by the energy unit to the energy storage unit, and the power charged by the energy unit in the same DC coupling unit are related.
- S5303 The overall controller acquires the second power value of each DC coupling unit in the N DC coupling units.
- the second power value is the maximum discharge power of the inverter unit in each DC coupling unit.
- the overall controller obtains the maximum discharge power of each inverter, wherein the jth The maximum discharge power of the ith inverter in the inverter unit in the DC coupling units is p pcs_max_discharge_ji .
- the overall controller determines the maximum discharge power of the inverter unit in each of the N DC coupling units according to the maximum discharge power of the at least one inverter, wherein the maximum discharge power of the inverter unit in the jth DC coupling unit
- the power, ie the second power value p bus_max_pcs_discharge_j is:
- the maximum discharge power of the inverter unit in each DC coupling unit is the sum of the maximum discharge powers of all inverters in the inverter unit in each DC coupling unit.
- the master controller determines the discharge adjustment demand value.
- the discharge adjustment demand value is less than the first candidate inverter power value of the DC coupling unit in which the first candidate inverter power value is greater than 0 and the first candidate inverter power value is greater than the corresponding second power value among the N DC coupling units. to the sum of the differences of the corresponding second power values.
- the discharge adjustment demand value Delta_pos_sum is:
- the first candidate inverter power value of the DC coupling unit is greater than 0, it can be understood that the inverter unit of the DC coupling unit is in a discharge state, and it can be considered whether the first candidate inverter power value of the DC coupling unit exceeds 0. If the maximum discharge power value of the inverter unit is exceeded, it indicates that the DC coupling unit cannot withstand the first candidate inverter power, the inverter unit is limited, and the discharge adjustment demand value is the value of the N DC coupling units. The DC coupling unit of the inverter unit is clipped exceeding the sum of the second power value.
- the overall controller determines the charging adjustment demand value.
- the charging adjustment demand value is less than the fourth power value of the DC coupling unit for which the first candidate inverter power value of the N DC coupling units is less than 0, and the first candidate inverter power value is less than the corresponding fourth power value.
- the fourth power value is the maximum charging power of the inverter unit in each DC coupling unit.
- the overall controller obtains the maximum charging power of each inverter, wherein the jth The maximum charging power of the ith inverter in the inverter unit in the DC coupling units is p pcs_max_charge_ji .
- the charging adjustment demand value Delta_neg_sum is:
- the negative sign of the first candidate inverter power value and the fourth power value indicates that the power direction is the charging direction.
- the charging direction can be understood as the direction from the power grid through the inverter unit to the energy storage unit, and its absolute value represents the magnitude of the power value. .
- the inverter unit of the DC coupling unit is in a charging state, and the absolute value of the first candidate inverter power value of the DC coupling unit can be considered. Whether the value exceeds the maximum charging power value of the inverter unit, if so, it indicates that the DC coupling unit cannot withstand the first candidate inverter power, the inverter unit is limited, and the discharge adjustment demand value is N DC
- the DC coupling unit in which the inverter unit is clipped in the coupling unit exceeds the sum of the fourth power value.
- the master controller determines to adjust the required power.
- the adjusted demand power is the absolute value of the difference between the discharge adjustment demand value and the charge adjustment demand value.
- the adjusted demand power Delta is:
- the total controller acquires the adjustment ratio value of each DC coupling unit in the N DC coupling units.
- the adjustment ratio value is the ratio of the exchange power value of each DC coupling unit to the sum of the exchange power values of the DC coupling units whose exchange power value is greater than 0.
- the adjustment ratio of the jth DC coupling unit in the N DC coupling units is:
- S5308 The overall controller determines the second candidate inverter power value of each of the N DC coupling units.
- the second candidate inverter power value of the DC coupling unit whose first candidate inverter power value is greater than 0 is the minimum value among the corresponding first candidate inverter power value and the corresponding second power value
- the first candidate inverter power value is the minimum value.
- the second candidate inverter power value of the DC coupling unit whose power value is less than 0 is the maximum value among the corresponding first candidate inverter power value and the corresponding fourth power value.
- p bus_pcs_to_grid_j_2 min(p bus_pcs_to_grid_j_1 , p bus_max_pcs_discharge_j ) (65)
- p bus_pcs_to_grid_j_2 max(p bus_pcs_to_grid_j_1 ,p bus_max_pcs_charge_j ) (66)
- p bus_pcs_to_grid_j_2 is the second candidate inverter power value of the jth DC coupling unit in the N DC coupling units
- p bus_pcs_to_grid_j_1 is the first candidate inverter power value of the jth DC coupling unit in the N DC coupling units
- p bus_max_pcs_discharge_j is the second power value of the jth DC coupling unit among the N DC coupling units
- p bus_max_pcs_charge_j is the fourth power value of the jth DC coupling unit among the N DC coupling units.
- the first inverter power value of the DC coupling unit with p bus_pcs_to_other_j ⁇ 0 is:
- the first inverter power value of the DC coupling unit with p bus_pcs_to_other_j >0 is:
- the first inverter power value of the DC coupling unit with p bus_pcs_to_other_j ⁇ 0 is:
- the first inverter power value of the DC coupling unit with p bus_pcs_to_other_j >0 is:
- the first inverter may be allocated according to the ratio of the maximum discharge power of each inverter to the second power value power value, or assign the first inverter power value according to the ratio of the maximum charging power of each inverter to the fourth power value.
- p pcs_to_grid_ji represents the inverter power of the i-th inverter in the inverter unit in the j-th DC coupling unit
- p pcs_max_discharge_ji represents the i-th inverter in the inverter unit in the j-th DC coupling unit.
- p pcs_max_charge_ji represents the maximum charging power of the i-th inverter in the inverter unit in the j-th DC coupling unit.
- the electric energy generated by the energy unit of the DC coupling unit can be supplied to the DC coupling unit and/or other DC coupling units.
- the energy storage unit is charged, thereby reducing the power waste of the energy unit.
- FIG. 14 shows a schematic structural diagram of a control device provided by an embodiment of the present application.
- the control device includes a processor 1410 and a communication interface 1420 .
- the control device may further include a memory 1430 .
- the memory 1430 may be included in the processor 1410 .
- the processor 1410, the communication interface 1420 and the memory 1430 communicate with each other through an internal connection path, the memory 1430 is used to store instructions, and the processor 1410 is used to execute the instructions stored in the memory 1430 to implement the control method provided by the embodiments of the present application.
- control device may be used to perform the functions of the general controller 101 in FIG. 1 , or the functions of the photovoltaic controllers 2400 to 2600 in FIG. 2 , or the functions of the energy storage controllers 3400 to 3600 in FIG. 3 .
- control device can also be used to execute the control method shown in any one of FIG. 5 or FIG. 13 .
- a component may be, but is not limited to, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and/or a computer.
- an application running on a computing device and the computing device may be components.
- One or more components may reside within a process and/or thread of execution, and a component may be localized on one computer and/or distributed between 2 or more computers.
- these components can execute from various computer readable media having various data structures stored thereon.
- a component may, for example, be based on a signal having one or more data packets (eg, data from two components interacting with another component between a local system, a distributed system, and/or a network, such as the Internet interacting with other systems via signals) Communicate through local and/or remote processes.
- data packets eg, data from two components interacting with another component between a local system, a distributed system, and/or a network, such as the Internet interacting with other systems via signals
- the disclosed system, apparatus and method may be implemented in other manners.
- the apparatus embodiments described above are only illustrative.
- the division of the units is only a logical function division. In actual implementation, there may be other division methods.
- multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented.
- the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be in electrical, mechanical or other forms.
- the units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.
- each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit.
- the functions, if implemented in the form of software functional units and sold or used as independent products, may be stored in a computer-readable storage medium.
- the technical solution of the present application can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution.
- the computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application.
- the aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk and other media that can store program codes .
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Abstract
一种电力系统和电力系统的控制方法,电力系统(100)包括N个直流耦合单元(102、103、104),N个直流母线(105、106、107)以及总控制器(101),N个直流耦合单元(102、103、104)与N个直流母线(105、106、107)一一对应,N个直流耦合单元(102、103、104)用于向电网(108)供电,每个直流耦合单元(102、103、104)包括能源单元(1022、1032),能源单元(1022、1032)用于产生电能;总控制器(101)用于:获取总入网需求功率,总入网需求功率是电网(108)所需的入网功率;获取第一限幅值,第一限幅值用于指示每个能源单元(1022、1032)可向电网(108)提供的最大放电功率;根据总入网需求功率和第一限幅值,确定第一入网功率值,第一入网功率值是指为每个能源单元(1022、1032)分配的输入电网(108)的功率值,至少一个直流耦合单元(102、103、104)处于第一限幅状态,第一限幅状态是指第一入网功率值等于其对应的第一限幅值,可以提高电力系统运行的可靠性。
Description
本申请要求于2021年4月30日提交国家知识产权局、申请号为202110481296.3、发明名称为“电力系统和电力系统的控制方法”的中国专利申请的优先权,其全部内容通过引用结合在本申请中。
本申请涉及电力系统的领域,并且更具体地,涉及电力系统和电力系统的控制方法。
近年来,随着风能、太阳能等新能源电力在电力系统中比重的增加,传统电力系统的结构特性、运行控制方式将产生变革,形成新能源电力系统。
然而,新能源电力具有较大的不确定性,若按照额定容量进行功率分配可能会导致新能源设备的能量转换效率较低,若按照每个设备当前的最大功率分配则容易造成电力系统中部分设备过压或过流,导致整个电力系统的可靠性下降。
因此,亟需一种电力系统和电力系统的控制方法,可以在提高电力系统运行的可靠性。
发明内容
本申请提供一种电力系统和电力系统的控制方法,能够提高电力系统运行的可靠性。
第一方面,提供了一种电力系统,所述电力系统包括N个直流耦合单元,N个直流母线以及控制器,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直流耦合单元用于向电网供电,所述N个直流耦合单元中的每个直流耦合单元包括能源单元,所述能源单元用于产生电能,N为正整数;所述总控制器用于:获取所述电网的总入网需求功率,所述总入网需求功率是所述电网所需的入网功率;获取所述N个直流耦合单元的第一限幅值,所述第一限幅值用于指示每个直流耦合单元中的能源单元可向电网提供的最大放电功率;根据所述总入网需求功率和所述N个直流耦合单元的第一限幅值,确定所述N个直流耦合单元的第一入网功率值,所述第一入网功率值是指为每个直流耦合单元中的能源单元分配的输入电网的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元处于第一限幅状态,所述第一限幅状态是指为直流耦合单元分配的第一入网功率值等于其对应的所述第一限幅值。
从而,在本申请中,电力系统中的总控制器可以获取直流耦合单元中能源单元当前可向电网提供的最大放电功率,也就是第一限幅值,总控制器根据第一限幅值对总入网需求功率对每个直流耦合单元分配第一入网功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性。
结合第一方面,在第一方面的某些实现方式中,所述N个直流耦合单元中的每个直流 耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收所述能源单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能;所述总控制器具体用于:将以下项中的最小值确定为每个直流耦合单元的第一限幅值:每个直流耦合单元的第一功率值、每个直流耦合单元的第二功率值,其中,所述第一功率值为每个直流耦合单元中的能源单元的最大放电功率,所述第二功率值为每个直流耦合单元中逆变单元的最大放电功率。
从而,在本申请中,总控制器将每个直流耦合单元的第一功率值和第二功率值之中的最小值作为该直流耦合单元的第一限幅值,从而与根据额定功率分配总入网需求功率相比,根据第一限幅值对总入网需求功率对每个直流耦合单元分配第一入网功率值,可以进一步提高电力系统能源单元产生电能的利用率。
结合第一方面,在第一方面的某些实现方式中,所述总控制器具体用于:进行多轮第一迭代计算,以确定所述N个直流耦合单元的第一入网功率值,所述多轮第一迭代计算中的每轮第一迭代计算包括:确定L
1个第一直流耦合单元,所述第一直流耦合单元为在之前的第一迭代计算中未被分配第一入网功率值的直流耦合单元,所述L
1为正整数且L
1≤N;计算所述L
1个第一直流耦合单元的第一候选入网功率值,所述第一候选入网功率值是根据所述总入网需求功率以及所述L
1个直流耦合单元的第一功率值确定的,所述第一功率值为每个直流耦合单元中的能源单元可提供的最大放电功率;根据所述L
1个第一直流耦合单元的第一候选入网功率值和第一限幅值,确定所述L
1个第一直流耦合单元的第一入网功率值。
从而,在本申请中,可以运用多轮第一迭代计算来为每个直流耦合单元分配第一入网功率值,从而提高电力系统运行的可靠性。
结合第一方面,在第一方面的某些实现方式中,所述总控制器具体用于:在所述L
1个第一直流耦合单元中确定L
2个第二直流耦合单元,所述第二直流耦合单元的第一候选入网功率值大于或等于其对应的第一限幅值,所述L
2为正整数;确定所述L
2个第二直流耦合单元的所述第一入网功率值,其中,所述L
2个第二直流耦合单元处于第一限幅状态。
从而,在本申请中,并不是直接将计算获得的第一候选入网功率值作为为每个直流耦合单元中的能源单元分配的输入电网的功率值,而是会确定处于第一限幅状态的L
2个第二直流耦合单元,为处于第一限幅状态的直流耦合单元分配对应的第一限幅值作为第一入网功率值,从而可以提高电力系统运行的可靠性。
结合第一方面,在第一方面的某些实现方式中,所述多轮第一迭代计算中的每轮第一迭代计算还包括:在L
1=L
2的情况下,确定结束所述多轮第一迭代计算;以及,在L
1>L
2的情况下,确定开始下一轮第一迭代计算。
结合第一方面,在第一方面的某些实现方式中,所述总控制器具体用于:确定所述L
1个第一直流耦合单元的第一候选入网功率值均小于其对应的第一限幅值;确定所述L
1个第一直流耦合单元的第一入网功率值为其对应的第一候选入网功率值。
结合第一方面,在第一方面的某些实现方式中,所述总控制器具体用于:满足以下条件,确定所述L
1个第一直流耦合单元的第一候选入网功率:
其中,P
bus_energy_to_grid_j表示所述L
1个第一直流耦合单元中第j个第一直流耦合单元的第一候选入网功率值,P
pref_1表示参考入网需求功率,所述参考入网需求功率为所述总入网需求功率与第一分配功率的差值,所述第一分配功率为在之前的第一迭代计算中已分配给直流耦合单元的第一入网功率值之和,P
bus_max_energy_j表示所述L
1个第一直流耦合单元中第j个第一直流耦合单元的第一功率值,
表示所述L
1个第一直流耦合单元的第一功率值之和,1≤j≤L
1。
从而,在本申请中,当某轮迭代计算中第一直流耦合单元的第一候选入网功率值均小于其对应的第一限幅值,也就是说,在某轮计算中第一直流耦合单元均为处于第一限幅状态,则可以确定L
1个第一直流耦合单元的第一入网功率值为其对应的第一候选入网功率值,可以进一步提高电力系统能源单元产生电能的利用率。
第二方面,提供了一种电力系统的控制方法,所述供电系统包括N个直流耦合单元、N个直流母线以及控制器,所述N个直流耦合单元用于向电网供电,其中,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直流耦合单元中的每个直流耦合单元包括能源单元,所述能源单元用于产生电能,N为正整数,所述方法包括:所述控制器获取所述电网的总入网需求功率,所述总入网需求功率是所述电网所需的入网功率;所述控制器获取所述N个直流耦合单元的第一限幅值,所述第一限幅值用于指示每个直流耦合单元中的能源单元可向电网提供的最大放电功率;所述控制器根据所述总入网需求功率和所述N个直流耦合单元的第一限幅值,确定所述N个直流耦合单元的第一入网功率值,所述第一入网功率值是指为每个直流耦合单元中的能源单元分配的输入电网的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元处于第一限幅状态,所述第一限幅状态是指为直流耦合单元分配的第一入网功率值等于其对应的所述第一限幅值。
从而,在本申请中,电力系统中的总控制器可以获取直流耦合单元中能源单元当前可向电网提供的最大放电功率,也就是第一限幅值,总控制器根据第一限幅值对总入网需求功率对每个直流耦合单元分配第一入网功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性。
结合第二方面,在第二方面的某些实现方式中,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收所述能源单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能,所述控制器获取所述N个直流耦合单元的第一限幅值,包括:所述控制器将以下项中的最小值确定为每个直流耦合单元的第一限幅值:每个直流耦合单元的第一功率值、每个直流耦合单元的第二功率值,其中,所述第一功率值为每个直流耦合单元中的能源单元的最大放电功率,所述第二功率值为每个直流耦合单元中逆变单元的最大放电功率。
结合第二方面,在第二方面的某些实现方式中,所述控制器根据所述总入网需求功率和所述N个直流耦合单元的第一限幅值,确定所述N个直流耦合单元的第一入网功率值,包括:所述控制器进行多轮第一迭代计算,以确定所述N个直流耦合单元的第一入网功率值,所述多轮第一迭代计算中的每轮第一迭代计算包括:所述控制器确定L
1个第一直流耦合单元,所述第一直流耦合单元为在之前的第一迭代计算中未被分配第一入网功率值的直流耦合单元,所述L
1为正整数且L
1≤N;所述控制器计算所述L
1个第一直流耦合单元的第一候选入网功率值,所述第一候选入网功率值是根据所述总入网需求功率以及所述 L
1个直流耦合单元的第一功率值确定的,所述第一功率值为每个直流耦合单元中的能源单元可提供的最大放电功率;所述控制器根据所述L
1个第一直流耦合单元的第一候选入网功率值和第一限幅值,确定所述L
1个第一直流耦合单元的第一入网功率值。
结合第二方面,在第二方面的某些实现方式中,所述控制器根据所述L
1个第一直流耦合单元的第一候选入网功率值和第一限幅值,确定所述L
1个第一直流耦合单元的第一入网功率值,包括:所述控制器在所述L
1个第一直流耦合单元中确定L
2个第二直流耦合单元,所述第二直流耦合单元的第一候选入网功率值大于或等于其对应的第一限幅值,所述L
2为正整数;所述控制器确定所述L
2个第二直流耦合单元的所述第一入网功率值,其中,所述L
2个第二直流耦合单元处于第一限幅状态。
结合第二方面,在第二方面的某些实现方式中,所述多轮第一迭代计算中的每轮第一迭代计算还包括:所述控制器在L
1=L
2的情况下,确定结束所述多轮第一迭代计算;以及,所述控制器在L
1>L
2的情况下,确定开始下一轮第一迭代计算。
结合第二方面,在第二方面的某些实现方式中,所述控制器根据所述L
1个第一直流耦合单元的第一候选入网功率值和第一限幅值,确定所述L
1个第一直流耦合单元的第一入网功率值,包括:确定所述L
1个第一直流耦合单元的第一候选入网功率值均小于其对应的第一限幅值;确定所述L
1个第一直流耦合单元的第一入网功率值为其对应的第一候选入网功率值。
结合第二方面,在第二方面的某些实现方式中,所述控制器计算L
1个第一直流耦合单元的第一候选入网功率值,包括:满足以下条件,确定所述L
1个第一直流耦合单元的第一候选入网功率:
其中,P
bus_energy_to_grid_j表示所述L
1个第一直流耦合单元中第j个第一直流耦合单元的第一候选入网功率值,P
pref表示参考入网需求功率,所述参考入网需求功率为所述总入网需求功率与第一分配功率的差值,所述第一分配功率为在之前的第一迭代计算中已分配给直流耦合单元的第一入网功率值之和,P
bus_max_energy_j表示所述L
1个第一直流耦合单元中第j个第一直流耦合单元的第一功率值,
表示所述L
1个第一直流耦合单元的第一功率值之和,1≤j≤L
1。
第三方面,提供了一种电力系统的控制方法,所述方法应用于电力系统,所述电力系统包括N个直流耦合单元、N个直流母线以及总控制器,所述N个直流耦合单元用于向电网供电,其中,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直流耦合单元中的每个直流耦合单元包括储能单元,所述储能单元用于储存电能,N为正整数,所述方法包括:所述总控制器获取所述电网的储能入网需求功率,所述储能入网需求功率是指需要所述储能单元为所述电网提供的入网功率;所述总控制器获取所述N个直流耦合单元的第二限幅值,所述第二限幅值用于指示每个直流耦合单元中的储能单元可向电网提供的最大放电功率;所述总控制器根据所述储能入网需求功率和所述N个直流耦合单元的第二限幅值,确定每个直流耦合单元的第二入网功率值,所述第二入网功率值是指为每个直流耦合单元中的储能单元分配的输入电网的功率值,其中,所述N个直流耦合单元中的 至少一个直流耦合单元中的储能单元处于第二限幅状态,所述第二限幅状态是指为直流耦合单元分配的第二入网功率值等于其对应的所述第二限幅值。
从而,在本申请中,电力系统中的总控制器可以获取直流耦合单元中储能单元当前可向电网提供的最大放电功率,也就是第二限幅值,总控制器根据第二限幅值对储能入网需求功率对每个直流耦合单元分配第二入网功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性,并且,电力系统中的储能单元可以均衡放电,提高储能单元中电力器件的生命周期。
结合第三方面,在第三方面的某些实现方式中,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收所述储能单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能,所述总控制器获取所述N个直流耦合单元的第二限幅值,包括:所述总控制器将以下项中的最小值确定为每个直流耦合单元的第二限幅值:每个直流耦合单元的第二功率值,每个直流耦合单元的第三功率值,其中,所述第二功率值为每个直流耦合单元中逆变单元的最大放电功率,所述第三功率值为每个直流耦合单元中的储能单元的最大放电功率。
从而,在本申请中,总控制器将每个直流耦合单元的第二功率值和第三功率值之中的最小值作为该直流耦合单元的第二限幅值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性。
结合第三方面,在第三方面的某些实现方式中,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元和能源单元,所述能源单元用于产生电能,所述逆变单元用于通过所述直流母线接收所述能源单元和/或储能单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能,所述总控制器获取所述N个直流耦合单元的第二限幅值,包括:所述总控制器将以下项中的最小值确定为每个直流耦合单元的第二限幅值:每个直流耦合单元的第三功率值,每个直流耦合单元的剩余放电功率值,其中,所述第三功率值为每个直流耦合单元中的储能单元的最大放电功率,所述剩余放电功率值为每个直流耦合单元的第二功率值减去第一入网功率值,所述第二功率值为每个直流耦合单元中逆变单元的最大放电功率,所述第一入网功率值是指为每个直流耦合单元中的能源单元分配的输入电网的功率值。
从而,在本申请中,在包括能源单元的电力系统中,总控制器将每个直流耦合单元的第二功率值和第四功率值之中的最小值作为该直流耦合单元的第二限幅值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性。
结合第三方面,在第三方面的某些实现方式中,所述总控制器根据所述储能入网需求功率和所述N个直流耦合单元的第二限幅值,确定所述N个直流耦合单元的第二入网功率值,包括:所述总控制器进行多轮第二迭代计算,以确定所述N个直流耦合单元的第二入网功率值,所述多轮第二迭代计算中的每轮第二迭代计算包括:所述总控制器确定M
1个第三直流耦合单元,所述第三直流耦合单元为在之前的第二迭代计算中未被分配第二入网功率值的直流耦合单元,所述M
1为正整数且M
1≤N;所述总控制器计算所述M
1个第三直流耦合单元的第二候选入网功率值,所述第二候选入网功率值是根据所述储能入网需求功率以及所述N个直流耦合单元的第一能量值确定的,所述第一能量值为每个直流耦合 单元中的储能单元当前存储的电能;所述总控制器根据所述M
1个第三直流耦合单元的第二候选入网功率值和第二限幅值,确定所述M
1个第三直流耦合单元的第二入网功率值。
结合第三方面,在第三方面的某些实现方式中,所述总控制器根据所述M
1个第三直流耦合单元的第二候选入网功率值和第二限幅值,确定所述M
1个第三直流耦合单元的第二入网功率值,包括:所述总控制器在所述M
1个第三直流耦合单元中确定M
2个第四直流耦合单元,所述第四直流耦合单元的第二候选入网功率值大于或等于其对应的第二限幅值,所述M
2为正整数;所述总控制器确定所述M
2个第四直流耦合单元的所述第二入网功率值,其中,所述M
2个直流耦合单元处于第二限幅状态。
结合第三方面,在第三方面的某些实现方式中,所述多轮第一迭代计算中的每轮第一迭代计算还包括:所述总控制器在M
1=M
2的情况下,确定结束所述多轮第二迭代计算;以及,所述总控制器在L
1>L
2的情况下,确定开始下一轮第二迭代计算。
结合第三方面,在第三方面的某些实现方式中,所述总控制器根据所述M
1个第三直流耦合单元的第二候选入网功率值和第二限幅值,确定所述M
1个第三直流耦合单元的第二入网功率值,包括:确定所述M
1个第三直流耦合单元的第三候选入网功率值均小于其对应的第二限幅值;确定所述M
1个第三直流耦合单元的第二入网功率值为其对应的第二候选入网功率值。
结合第三方面,在第三方面的某些实现方式中,,所述总控制器计算M
1个第三直流耦合单元的第二候选入网功率值,包括:确定参考储能入网需求功率,所述参考储能入网需求功率为所述储能入网需求功率减去在之前的第二迭代计算中已分配给直流耦合单元的第二入网功率值之和的差值;满足以下条件,确定所述M
1个第三直流耦合单元的第二候选入网功率值:
其中,P
bus_bat_to_grid_j表示所述M
1个第三直流耦合单元中第j个第三直流耦合单元的第二候选入网功率值,P
pref_2表示参考储能入网需求功率,所述参考储能入网需求功率为所述储能入网需求功率减去在之前的第二迭代计算中已分配给直流耦合单元的第二入网功率值之和的差值,SOE
bus_j表示所述M
1个第三直流耦合单元中第j个第三直流耦合单元的第一能量值,
表示所述M
1个第三直流耦合单元的第一能量值之和,1≤j≤M
1。
从而,在本申请中,并不是直接将计算获得的第二候选入网功率值作为为每个直流耦合单元中的储能单元分配的输入电网的功率值,而是会确定处于第二限幅状态的M
2个第四直流耦合单元,为处于第二限幅状态的直流耦合单元分配对应的第二限幅值作为第二入网功率值,从而可以提高电力系统运行的可靠性。
第四方面,提供了一种电力系统,所述电力系统包括N个直流耦合单元、N个直流母线以及总控制器,所述N个直流耦合单元与所述N个直流母线一一对应,其中,所述N个直流耦合单元用于向电网供电,所述N个直流耦合单元中的每个直流耦合单元包括储能单元,所述储能单元用于储存电能,N为正整数;所述总控制器用于:获取所述电网的储能入网需求功率,所述储能入网需求功率是指需要所述储能单元为所述电网提供的入网功率;获取所述N个直流耦合单元的第二限幅值,所述第二限幅值用于指示每个直流耦合单 元中的储能单元可向电网提供的最大放电功率;根据所述储能入网需求功率和所述N个直流耦合单元的第二限幅值,确定每个直流耦合单元的第二入网功率值,所述第二入网功率值是指为每个直流耦合单元中的储能单元分配的输入电网的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元中的储能单元处于第二限幅状态,所述第二限幅状态是指为直流耦合单元分配的第二入网功率值等于其对应的所述第二限幅值。
从而,在本申请中,电力系统中的总控制器可以获取直流耦合单元中储能单元当前可向电网提供的最大放电功率,也就是第二限幅值,总控制器根据第一限幅值对储能入网需求功率对每个直流耦合单元分配第二入网功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性,并且,电力系统中的储能单元可以均衡放电,提高储能单元中电力器件的生命周期。
结合第四方面,在第四方面的某些实施方式中,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收所述储能单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能;所述总控制器具体用于:总控制器获取所述N个直流耦合单元的第二限幅值,包括:所述总控制器将以下项中的最小值确定为每个直流耦合单元的第二限幅值:每个直流耦合单元的第二功率值,每个直流耦合单元的第三功率值,其中,所述第二功率值为每个直流耦合单元中逆变单元的最大放电功率,所述第三功率值为每个直流耦合单元中的储能单元的最大放电功率。
结合第四方面,在第四方面的某些实施方式中,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元和能源单元,所述能源单元用于产生电能,所述逆变单元用于通过所述直流母线接收所述能源单元和/或储能单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能;所述总控制器具体用于获取所述N个直流耦合单元的第二限幅值,包括:将以下项中的最小值确定为每个直流耦合单元的第二限幅值:每个直流耦合单元的第三功率值,每个直流耦合单元的剩余放电功率值,其中,所述第三功率值为每个直流耦合单元中的储能单元的最大放电功率,所述剩余放电功率值为每个直流耦合单元的第二功率值减去第一入网功率值,所述第二功率值为每个直流耦合单元中逆变单元的最大放电功率,所述第一入网功率值是指为每个直流耦合单元中的能源单元分配的输入电网的功率值。
结合第四方面,在第四方面的某些实施方式中,所述控制器具体用于:进行多轮第二迭代计算,以确定所述N个直流耦合单元的第二入网功率值,所述多轮第二迭代计算中的每轮第二迭代计算包括:确定M
1个第三直流耦合单元,所述第三直流耦合单元为在之前的第二迭代计算中未被分配第二入网功率值的直流耦合单元,所述M
1为正整数且M
1≤N;计算所述M
1个第三直流耦合单元的第二候选入网功率值,所述第二候选入网功率值是根据所述储能入网需求功率以及所述N个直流耦合单元的第一能量值确定的,所述第一能量值为每个直流耦合单元中的储能单元当前存储的电能;根据所述M
1个第三直流耦合单元的第二候选入网功率值和第二限幅值,确定所述M
1个第三直流耦合单元的第二入网功率值。
结合第四方面,在第四方面的某些实施方式中,所述控制器具体用于:在所述M
1个第三直流耦合单元中确定M
2个第四直流耦合单元,所述第四直流耦合单元的第二候选入网功率值大于或等于其对应的第二限幅值,所述M
2为正整数;确定所述M
2个第四直流 耦合单元的所述第二入网功率值,其中,所述M
2个直流耦合单元处于第二限幅状态。
结合第四方面,在第四方面的某些实施方式中,所述控制器具体用于:在M
1=M
2的情况下,确定结束所述多轮第二迭代计算;以及,在L
1>L
2的情况下,确定开始下一轮第二迭代计算。
结合第四方面,在第四方面的某些实施方式中,所述控制器具体用于:确定所述M
1个第三直流耦合单元的第三候选入网功率值均小于其对应的第二限幅值;确定所述M
1个第三直流耦合单元的第二入网功率值为其对应的第二候选入网功率值。
结合第四方面,在第四方面的某些实施方式中,所述控制器具体用于:确定参考储能入网需求功率,所述参考储能入网需求功率为所述储能入网需求功率减去在之前的第二迭代计算中已分配给直流耦合单元的第二入网功率值之和的差值;满足以下条件,确定所述M
1个第三直流耦合单元的第二候选入网功率值:
其中,P
bus_bat_to_grid_j表示所述M
1个第三直流耦合单元中第j个第三直流耦合单元的第二候选入网功率值,P
pref_2表示参考储能入网需求功率,所述参考储能入网需求功率为所述储能入网需求功率减去在之前的第二迭代计算中已分配给直流耦合单元的第二入网功率值之和的差值,SOE
bus_j表示所述M
1个第三直流耦合单元中第j个第三直流耦合单元的第一能量值,
表示所述M
1个第三直流耦合单元的第一能量值之和,1≤j≤M
1。
第五方面,提供了一种电力系统,所述电力系统包括N个直流耦合单元、N个直流母线以及总控制器,所述N个直流耦合单元与所述N个直流母线一一对应,其中,所述N个直流耦合单元用于与电网传输电能,所述N个直流耦合单元中的每个直流耦合单元包括逆变单元,所述N个直流耦合单元中的每个直流耦合单元还包括能源单元和/或储能单元,所述逆变单元用于通过所述直流母线,接收所述能源单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能,或者,所述逆变单元用于通过所述直流母线吸收所述电网的电能,以及对电能进行交流转直流变换后,向储能单元提供电能,所述能源单元用于产生电能,所述储能单元用于储存电能;所述总控制器用于:获取N个直流耦合单元的放电需求功率,所述放电需求功率用于指示为每个直流耦合单元中的能源单元分配的给N个直流耦合单元的储能单元充电的功率;获取N个直流耦合单元的充电需求功率,所述充电需求功率用于指示为每个直流耦合单元中的储能单元分配的从N个直流耦合单元的能源单元获取的功率;根据所述N个直流耦合单元的放电需求功率和所述N个直流耦合单元的充电需求功率确定每个直流耦合单元的第一逆变功率值,所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元向电网提供电能的功率,或所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元从电网吸收电能的功率。
从而,在本申请中,可以通过确定N个直流耦合单元中逆变单元的第一逆变功率值,实现将直流耦合单元的能源单元产生的电能给该直流耦合单元和/或其它直流耦合单元的储能单元充电,从而可以减少能源单元的电能浪费。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:获取总充电需求功率,所述总充电需求功率是为N个直流耦合单元中的储能单元分配的从N个直流 耦合单元中的能源单元获取的总功率;获取所述N个直流耦合单元的第三限幅值,所述第三限幅值用于指示每个直流耦合单元中的储能单元可提供的最大充电功率;根据所述总充电需求功率和所述N个直流耦合单元的第三限幅值,确定每个直流耦合单元的充电需求功率,其中,所述N个直流耦合单元中的至少一个直流耦合单元中处于第三限幅状态,所述第三限幅状态是指为直流耦合单元分配的充电需求功率等于其对应的所述第三限幅值。
从而,在本申请中,可以根据第三限幅值确定每个直流耦合单元中的充电需求功率,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性,并且,电力系统中的储能单元可以均衡充电,提高储能单元中电力器件的生命周期。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:进行多轮第三迭代计算,以确定所述N个直流耦合单元的充电需求功率,所述多轮第三迭代计算中的每轮第三迭代计算包括:确定T
1个第五直流耦合单元,所述第五直流耦合单元为在之前的第三迭代计算中未被分配充电需求功率的直流耦合单元,所述T
1为正整数且T
1≤N;计算所述T
1个第五直流耦合单元的候选充电需求功率,所述候选充电需求功率是根据所述总充电需求功率以及所述N个直流耦合单元的第二能量值确定的,所述第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差;根据所述T
1个第五直流耦合单元的候选充电需求功率和第三限幅值,确定所述T
1个第五直流耦合单元的充电需求功率。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:在所述T
1个第五直流耦合单元中确定T
2个第六直流耦合单元,所述第六直流耦合单元的候选充电需求功率大于或等于其对应的第三限幅值,所述T
2为正整数;确定所述T
2个第六直流耦合单元的充电需求功率,其中,所述T
2个第六直流耦合单元处于第三限幅状态。
结合第五方面,在第五方面的某些实现方式中,所述多轮第三迭代计算中的每轮第一迭代计算还包括:在T
1=T
2的情况下,确定结束所述多轮第三迭代计算;以及,在T
1>T
2的情况下,确定开始下一轮第三迭代计算。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:确定所述T
1个第五直流耦合单元的候选充电需求功率均小于其对应的第三限幅值;确定所述T
1个第五直流耦合单元的充电需求功率为其对应的候选充电需求功率。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:确定参考充电需求功率,所述参考充电需求功率为所述充电需求功率减去在之前的第三迭代计算中已分配给直流耦合单元的充电需求功率之和的差值;满足以下条件,确定所述T
1个第五直流耦合单元的候选充电需求功率:
其中,p
bus_bat_charge_j表示所述T
1个第五直流耦合单元中第j个第五直流耦合单元的候选充电需求功率,P
pref_3表示参考总充电需求功率,所述参考总充电需求功率为所述充电需求功率减去在之前的第三迭代计算中已分配给直流耦合单元的充电需求功率之和的差值,SOE
bus_able_j表示所述T
1个第五直流耦合单元中第j个第五直流耦合单元的第二能量值,
表示所述T
1个第五直流耦合单元的第二能量值之和,1≤j≤T
1。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:确定N个直流耦合单元的交换功率,所述交换功率为每个直流耦合单元的放电需求功率减去其对应的充电需求功率;根据所述N个直流耦合单元的交换功率确定调整需求功率;根据所述调整需求功率和所述N个直流耦合单元的交换功率确定N个直流耦合单元的第一逆变功率值。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:根据所述N个直流耦合单元的交换功率确定所述N个直流耦合单元的第一候选逆变功率值,所述第一候选逆变功率值为每个直流耦合单元的交换功率与对应的第一入网功率值之和,或者,所述第一候选逆变功率值为每个直流耦合单元的交换功率减去吸收功率值的差值,其中,所述第一入网功率值为是指为每个直流耦合单元中的能源单元分配的输入电网的功率值,所述吸收功率值为为每个直流耦合单元中的储能单元分配的吸收电网的功率值;根据所述N个直流耦合单元的第一候选逆变功率值和所述N个直流耦合单元的交换功率确定所述调整需求功率。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:确定放电调整需求值,所述放电调整需求值为所述N个直流耦合单元中第一候选逆变功率值大于0,且第一候选逆变功率值大于对应的第二功率值的直流耦合单元的第一候选逆变功率值减去对应的第二功率值的差值之和;确定充电调整需求值,所述充电调整需求值为所述N个直流耦合单元中第一候选逆变功率值小于0,且第一候选逆变功率值小于对应的第四功率值的直流耦合单元的第四功率值减去对应的第一候选逆变功率值的差值之和,其中,所述第二功率值为每个直流耦合单元中的逆变单元的最大放电功率,所述第四功率值为每个直流耦合单元中逆变单元的最大充电功率;确定所述调整需求功率,所述调整需求功率为所述放电调整需求值减去所述充电调整需求值的差值的绝对值。
结合第五方面,在第五方面的某些实现方式中,所述总控制器具体用于:所述总控制器具体用于:确定N个直流耦合单元的调整比例值,所述调整比例值为每个直流耦合单元的交换功率值占交换功率值大于0的直流耦合单元的交换功率值之和的占比;确定N个直流耦合单元的第二候选逆变功率值,其中,第一候选逆变功率值大于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第二功率值中的最小值,第一候选逆变功率值小于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第四功率值中的最大值;在确定放电需求功率大于充电需求功率的情况下,确定交换功率值小于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值减去调整需求功率与对应的调整比例值乘积的差值,确定交换功率大于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值;以及在确定放电需求功率小于充电需求功率的情况下,确定交换功率值小于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值,确定交换功率值大于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值减去调整需求功率与对应的调整比例值乘积的差值。
第六方面,提供了一种电力系统的控制方法,所述方法应用于电力系统,所述电力系统包括N个直流耦合单元、N个直流母线以及控制器,所述N个直流耦合单元用于与电网传输电能,其中,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直 流耦合单元中的每个直流耦合单元包括逆变单元,所述N个直流耦合单元中的每个直流耦合单元还包括能源单元和/或储能单元,所述逆变单元用于通过所述直流母线,接收所述能源单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能,或者,所述逆变单元用于通过所述直流母线吸收所述电网的电能,以及对电能进行交流转直流变换后,向储能单元提供电能,所述能源单元用于产生电能,所述储能单元用于储存电能,所述方法包括:所述控制器获取N个直流耦合单元的放电需求功率,所述放电需求功率用于指示为每个直流耦合单元中的能源单元分配的给N个直流耦合单元的储能单元充电的功率;所述控制器获取N个直流耦合单元的充电需求功率,所述充电需求功率用于指示为每个直流耦合单元中的储能单元分配的从N个直流耦合单元的能源单元获取的功率;所述控制器根据所述N个直流耦合单元的放电需求功率和所述N个直流耦合单元的充电需求功率确定每个直流耦合单元的第一逆变功率值,所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元向电网提供电能的功率,或所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元从电网吸收电能的功率。
从而,在本申请中,可以通过确定N个直流耦合单元中逆变单元的第一逆变功率值,实现将直流耦合单元的能源单元产生的电能给该直流耦合单元和/或其它直流耦合单元的储能单元充电,从而可以减少能源单元的电能浪费。
结合第六方面,在第六方面的某些实现方式中,所述控制器获取N个直流耦合单元的充电需求功率,包括:所述控制器获取总充电需求功率,所述总充电需求功率是为N个直流耦合单元中的储能单元分配的从N个直流耦合单元中的能源单元获取的总功率;所述控制器获取所述N个直流耦合单元的第三限幅值,所述第三限幅值用于指示每个直流耦合单元中的储能单元可提供的最大充电功率;所述控制器根据所述总充电需求功率和所述N个直流耦合单元的第三限幅值,确定每个直流耦合单元的充电需求功率,其中,所述N个直流耦合单元中的至少一个直流耦合单元中处于第三限幅状态,所述第三限幅状态是指为直流耦合单元分配的充电需求功率等于其对应的所述第三限幅值。
结合第六方面,在第六方面的某些实现方式中,述控制器根据所述总充电需求功率和所述N个直流耦合单元的第三限幅值,确定每个直流耦合单元的充电需求功率,包括:所述控制器进行多轮第三迭代计算,以确定所述N个直流耦合单元的充电需求功率,所述多轮第三迭代计算中的每轮第三迭代计算包括:所述控制器确定T
1个第五直流耦合单元,所述第五直流耦合单元为在之前的第三迭代计算中未被分配充电需求功率的直流耦合单元,所述T
1为正整数且T
1≤N;所述控制器计算所述T
1个第五直流耦合单元的候选充电需求功率,所述候选充电需求功率是根据所述总充电需求功率以及所述N个直流耦合单元的第二能量值确定的,所述第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差;所述控制器根据所述T
1个第五直流耦合单元的候选充电需求功率和第三限幅值,确定所述T
1个第五直流耦合单元的充电需求功率。
结合第六方面,在第六方面的某些实现方式中,所述控制器根据所述T
1个第五直流耦合单元的候选充电需求功率和第三限幅值,确定所述T
1个第五直流耦合单元的充电需求功率,包括:所述控制器在所述T
1个第五直流耦合单元中确定T
2个第六直流耦合单元,所述第六直流耦合单元的候选充电需求功率大于或等于其对应的第三限幅值,所述T
2为正整数;所述控制器确定所述T
2个第六直流耦合单元的充电需求功率,其中,所述T
2个 第六直流耦合单元处于第三限幅状态。
结合第六方面,在第六方面的某些实现方式中,所述多轮第三迭代计算中的每轮第一迭代计算还包括:所述控制器在T
1=T
2的情况下,确定结束所述多轮第三迭代计算;以及,所述控制器在T
1>T
2的情况下,确定开始下一轮第三迭代计算。
结合第六方面,在第六方面的某些实现方式中,所述控制器根据所述T
1个第五直流耦合单元的候选充电需求功率和第三限幅值,确定所述T
1个第五直流耦合单元的充电需求功率,包括:确定所述T
1个第五直流耦合单元的候选充电需求功率均小于其对应的第三限幅值;确定所述T
1个第五直流耦合单元的充电需求功率为其对应的候选充电需求功率。
结合第六方面,在第六方面的某些实现方式中,所述控制器计算T
1个第五直流耦合单元的候选充电需求功率,包括:确定参考充电需求功率,所述参考充电需求功率为所述充电需求功率减去在之前的第三迭代计算中已分配给直流耦合单元的充电需求功率之和的差值;结合以下方面,确定所述T
1个第五直流耦合单元的候选充电需求功率:
其中,P
bus_bat_to_grid_j表示所述T
1个第五直流耦合单元中第j个第五直流耦合单元的第一候选充电功率值,P
max_energy_to_bat表示参考充电需求功率,所述参考充电需求功率为所述充电需求功率减去在之前的第三迭代计算中已分配给直流耦合单元的充电需求功率之和的差值,SOE
bus_able_j表示所述T
1个第五直流耦合单元中第j个第五直流耦合单元的第二能量值,
表示所述T
1个第五直流耦合单元的第二能量值之和,1≤j≤T
1。
结合第六方面,在第六方面的某些实现方式中,所述控制器根据所述N个直流耦合单元的放电需求功率和所述N个直流耦合单元的充电需求功率确定每个直流耦合单元的第一逆变功率值,包括:所述控制器确定N个直流耦合单元的交换功率,所述交换功率为每个直流耦合单元的放电需求功率减去其对应的充电需求功率;所述控制器根据所述N个直流耦合单元的交换功率确定调整需求功率;所述控制器根据所述调整需求功率和所述N个直流耦合单元的交换功率确定N个直流耦合单元的第一逆变功率值。
结合第六方面,在第六方面的某些实现方式中,所述控制器根据所述N个直流耦合单元的交换功率确定调整需求功率,包括:所述控制器根据所述N个直流耦合单元的交换功率确定所述N个直流耦合单元的第一候选逆变功率值,所述第一候选逆变功率值为每个直流耦合单元的交换功率与对应的第一入网功率值之和,或者,所述第一候选逆变功率值为每个直流耦合单元的交换功率减去吸收功率值的差值,其中,所述第一入网功率值为是指为每个直流耦合单元中的能源单元分配的输入电网的功率值,所述吸收功率值为为每个直流耦合单元中的储能单元分配的吸收电网的功率值;所述控制器根据所述N个直流耦合单元的第一候选逆变功率值和所述N个直流耦合单元的交换功率确定所述调整需求功率。
结合第六方面,在第六方面的某些实现方式中,所述控制器根据所述N个直流耦合单元的第一候选逆变功率值和所述N个直流耦合单元的交换功率确定所述调整需求功率,包括:所述控制器确定放电调整需求值,所述放电调整需求值为所述N个直流耦合单元中第一候选逆变功率值大于0,且第一候选逆变功率值大于对应的第二功率值的直流耦合单元 的第一候选逆变功率值减去对应的第二功率值的差值之和;所述控制器确定充电调整需求值,所述充电调整需求值为所述N个直流耦合单元中第一候选逆变功率值小于0,且第一候选逆变功率值小于对应的第四功率值的直流耦合单元的第四功率值减去对应的第一候选逆变功率值的差值之和,其中,所述第一功率值为每个直流耦合单元中的逆变单元的最大放电功率,所述第四功率值为每个直流耦合单元中逆变单元的最大充电功率;所述控制器确定所述调整需求功率,所述调整需求功率为所述放电调整需求值减去所述充电调整需求值的差值的绝对值。
结合第六方面,在第六方面的某些实现方式中,所述控制器根据所述调整需求功率和所述N个直流耦合单元的交换功率确定N个直流耦合单元的第一逆变功率值,包括:所述控制器确定N个直流耦合单元的调整比例值,所述调整比例值为每个直流耦合单元的交换功率值占交换功率值大于0的直流耦合单元的交换功率值之和的占比;所述控制器确定N个直流耦合单元的第二候选逆变功率值,其中,第一候选逆变功率值大于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第二功率值中的最小值,第一候选逆变功率值小于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第四功率值中的最大值;所述控制器在确定放电需求功率大于充电需求功率的情况下,确定交换功率值小于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值减去调整需求功率与对应的调整比例值乘积的差值,确定交换功率大于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值;以及所述控制器在确定放电需求功率小于充电需求功率的情况下,确定交换功率值小于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值,确定交换功率值大于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值减去调整需求功率与对应的调整比例值乘积的差值。
第七方面,提供了一种电力系统的控制方法,所述方法应用于电力系统,所述电力系统包括N个直流耦合单元、N个直流母线以及总控制器,所述N个直流耦合单元用于从电网吸收功率,其中,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直流耦合单元中的每个直流耦合单元包括储能单元,所述储能单元用于储存电能,N为正整数,所述方法包括:所述总控制器获取所述电网的吸收需求功率,所述吸收需求功率为所述N个直流耦合单元中储能单元需要从电网吸收的功率;所述总控制器获取所述N个直流耦合单元的第四限幅值,所述第四限幅值用于指示每个直流耦合单元可提供的最大充电功率;所述总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,所述吸收功率值是指为每个直流耦合单元中的能源单元分配的从电网吸收的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元处于第四限幅状态,所述第四限幅状态是指为直流耦合单元分配的吸收功率值等于其对应的第四限幅值。
从而,在本申请中,电力系统中的总控制器可以获取每个直流耦合单元可提供的最大充电功率,也就是直流耦合单元中储能单元当前可从电网吸收的最大充电功率,也就是第四限幅值,总控制器根据第四限幅值对吸收需求功率值对每个直流耦合单元分配吸收功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性。
结合第七方面,在第七方面的某些实现方式中,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收电网的电能,以及对电能进行交流转直流变换之后,向所述储能单元传输电能,所述方法还包括:所述总控制器获取所述N个直流耦合单元的第四限幅值,包括:所述总控制器将以下项中的最小值确定为每个直流耦合单元的第四限幅值:每个直流耦合单元的第四功率值的绝对值,每个直流耦合单元的第五功率值,其中,所述第四功率值为每个直流耦合单元中逆变单元的最大充电功率,所述第五功率值为每个直流耦合单元中储能单元的最大充电功率。
从而,在本申请中,总控制器将每个直流耦合单元的第四功率值和第五功率值之中的最小值作为该直流耦合单元的第四限幅值,从而可以提高电力系统运行的可靠性。
结合第七方面,在第七方面的某些实现方式中,所述总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,包括:所述总控制器进行多轮第四迭代计算,以确定所述N个直流耦合单元的吸收功率值,所述多轮第四迭代计算中的每轮第四迭代计算包括:
结合第七方面,在第七方面的某些实现方式中,所述总控制器确定Q
1个第七直流耦合单元,所述第七直流耦合单元为在之前的第四迭代计算中未被分配吸收功率值的直流耦合单元,所述Q
1为正整数,且Q
1≤N;所述总控制器计算所述Q
1个第七直流耦合单元的第一候选吸收功率值,所述第一候选吸收功率值是根据所述吸收需求功率以及所述Q
1个直流耦合单元的第二能量值确定的,所述第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差;所述总控制器根据所述Q
1个第七直流耦合单元的第一候选吸收功率值和第四限幅值,确定所述Q
1个第七直流耦合单元的吸收功率值。
结合第七方面,在第七方面的某些实现方式中,所述总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,包括:所述总控制器在所述Q
1个第七直流耦合单元中确定Q
2个第八直流耦合单元,所述第八直流耦合单元的第一候选吸收功率值大于或等于其对应的第四限幅值,所述Q
2为正整数;所述总控制器确定所述Q
2个第八直流耦合单元的吸收功率值,其中,所述Q
2个第八直流耦合单元处于所述第四限幅状态。
结合第七方面,在第七方面的某些实现方式中,所述多轮第四迭代计算中的每轮第四迭代计算还包括:所述总控制器在Q
1=Q
2的情况下,确定结束所述多轮第四迭代计算;以及,所述总控制器在Q
1>Q
2的情况下,确定开始下一轮第四迭代计算。
结合第七方面,在第七方面的某些实现方式中,所述总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,包括:确定所述Q
1个第七直流耦合单元的第一候选吸收功率值均小于其对应的第四限幅值;确定所述Q
1个第七直流耦合单元的吸收功率值为其对应的第一候选吸收功率值。
结合第七方面,在第七方面的某些实现方式中,所述总控制器计算Q
1个第七直流耦合单元的第一候选吸收功率值,包括:确定第一参考吸收需求功率,所述第一参考吸收需求功率为所述吸收需求功率减去在之前的第四迭代计算中已分配给直流耦合单元的吸收功率值之和的差值;满足以下条件,确定Q
1个第七直流耦合单元的第一候选吸收功率值:
其中P
bus_bat_from_grid_j表示所述Q
1个第七直流耦合单元中第j个直流耦合单元的第一候选吸收功率值,P
ref_absorb表示第一参考吸收需求功率,所述第一参考吸收需求功率为所述吸收需求功率减去在之前的第四迭代计算中已分配给直流耦合单元的吸收功率值之和的差值,SOE
bus_able_j表示所述Q
1个第七直流耦合单元中第j个第七直流耦合单元的第二能量值,
表示所述Q
1个第七直流耦合单元的第二能量值之和,1≤j≤Q
1。
从而,在本申请中,通过迭代算法为每个直流耦合单元分配吸收功率,可以实现直流耦合单元中储能单元的均衡放电,可以进一步提高储能单元电力器件的生命周期。
第八方面,提供了一种电力系统,所述电力系统包括N个直流耦合单元,N个直流母线以及控制器,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直流耦合单元用于从电网吸收功率,所述N个直流耦合单元中的每个直流耦合单元包括储能单元,所述储能单元用于储存电能,N为正整数;所述总控制器用于:获取所述电网的吸收需求功率,所述吸收需求功率为所述N个直流耦合单元中储能单元需要从电网吸收的功率;获取所述N个直流耦合单元的第四限幅值,所述第四限幅值用于指示每个直流耦合单元可提供的最大充电功率;根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,所述吸收功率值是指为每个直流耦合单元中的能源单元分配的从电网吸收的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元处于第四限幅状态,所述第四限幅状态是指为直流耦合单元分配的吸收功率值等于其对应的第四限幅值。
从而,在本申请中,电力系统中的总控制器可以获取每个直流耦合单元可提供的最大充电功率,也就是直流耦合单元中储能单元当前可从电网吸收的最大充电功率,也就是第四限幅值,总控制器根据第四限幅值对吸收需求功率值对每个直流耦合单元分配吸收功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性。
结合第八方面,在第八方面的某些实现方式中,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收电网的电能,以及对电能进行交流转直流变换之后,向所述储能单元传输电能;所述总控制器具体用于:将以下项中的最小值确定为每个直流耦合单元的第四限幅值:每个直流耦合单元的第四功率值的绝对值,每个直流耦合单元的第五功率值,其中,所述第四功率值为每个直流耦合单元中逆变单元的最大充电功率,所述第五功率值为每个直流耦合单元中储能单元的最大充电功率。
结合第八方面,在第八方面的某些实现方式中,所述总控制器具体用于:进行多轮第四迭代计算,以确定所述N个直流耦合单元的吸收功率值,所述多轮第四迭代计算中的每轮第四迭代计算包括:所述总控制器确定Q
1个第七直流耦合单元,所述第七直流耦合单元为在之前的第四迭代计算中未被分配吸收功率值的直流耦合单元,所述Q
1为正整数,且Q
1≤N;所述总控制器计算所述Q
1个第七直流耦合单元的第一候选吸收功率值,所述第一候选吸收功率值是根据所述吸收需求功率以及所述Q
1个直流耦合单元的第二能量值 确定的,所述第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差;所述总控制器根据所述Q
1个第七直流耦合单元的第一候选吸收功率值和第四限幅值,确定所述Q
1个第七直流耦合单元的吸收功率值。
结合第八方面,在第八方面的某些实现方式中,所述总控制器具体用于:在所述Q
1个第七直流耦合单元中确定Q
2个第八直流耦合单元,所述第八直流耦合单元的第一候选吸收功率值大于或等于其对应的第四限幅值,所述Q
2为正整数;所述总控制器确定所述Q
2个第八直流耦合单元的吸收功率值,其中,所述Q
2个第八直流耦合单元处于所述第四限幅状态。
结合第八方面,在第八方面的某些实现方式中,所述多轮第四迭代计算中的每轮第四迭代计算还包括:所述总控制器在Q
1=Q
2的情况下,确定结束所述多轮第四迭代计算;以及,所述总控制器在Q
1>Q
2的情况下,确定开始下一轮第四迭代计算。
结合第八方面,在第八方面的某些实现方式中,所述总控制器具体用于:确定所述Q
1个第七直流耦合单元的第一候选吸收功率值均小于其对应的第四限幅值;确定所述Q
1个第七直流耦合单元的吸收功率值为其对应的第一候选吸收功率值。
结合第八方面,在第八方面的某些实现方式中,所述总控制器具体用于:确定第一参考吸收需求功率,所述第一参考吸收需求功率为所述吸收需求功率减去在之前的第四迭代计算中已分配给直流耦合单元的吸收功率值之和的差值;满足以下条件,确定Q
1个第七直流耦合单元的第一候选吸收功率值:
其中P
bus_bat_from_grid_j表示所述Q
1个第七直流耦合单元中第j个直流耦合单元的第一候选吸收功率值,P
ref_absorb表示第一参考吸收需求功率,所述第一参考吸收需求功率为所述吸收需求功率减去在之前的第四迭代计算中已分配给直流耦合单元的吸收功率值之和的差值,SOE
bus_able_j表示所述Q
1个第七直流耦合单元中第j个第七直流耦合单元的第二能量值,
表示所述Q
1个第七直流耦合单元的第二能量值之和,1≤j≤Q
1。
图1是适用本申请电力系统的一例示意图;
图2是适用本申请的能源单元的一例示意性结构图;
图3是适用本申请的储能单元的一例示意性结构图;
图4是适用本申请的逆变单元的一例示意性结构图;
图5是本申请提供的为直流耦合单元分配第一入网功率值的示意性流程图;
图6是本申请提供的确定第一入网功率值的一例示意性流程图;
图7是本申请提供的为直流耦合单元分配第二入网功率值的示意性流程图;
图8是本申请提供的确定第二入网功率值的一例示意性流程图;
图9是本申请提供的为直流耦合单元分配第一逆变功率值的示意性流程图;
图10是本申请提供的确定第一逆变功率值的示意性流程图;
图11是本申请提供的为直流耦合单元分配吸收功率值的示意性流程图;
图12是本申请提供的确定吸收功率值的一例示意性流程图;
图13是本申请提供的为直流耦合单元分配第一逆变功率值的另一例示意性流程图;
图14是适用本申请的装置的示意性结构图。
下面将结合附图,对本申请中的技术方案进行描述。
本申请提供的技术方案可以应用于各种电力系统,为便于理解本申请实施例,首先结合图1详细说明适用于本申请实施例提供的一种电力系统。图1示出了本申请实施例提供的电力系统100的示意图,如图1所示,该电力系统可以包括至少一个总控制器,如图1所示的总控制器101;该电力系统100还可以包括至少一个直流耦合单元,如图1所示的直流耦合单元102至104;该电力系统100还可以包括至少一个直流母线,如图1所示的直流母线105至107。其中,直流耦合单元102至104与直流母线105至107一一对应。总控制器101可以对直流耦合单元102至104进行控制。从而,图1中的总控制器101,直流耦合单元102至104,和直流母线105至107构成了一个可以和电网108进行电能传输的电力系统,也就是说直流耦合单元102至104可以向电网108供电,直流耦合单元102至104也可以从电网108吸收电能。
其中,每个直流耦合单元包括逆变单元,如图1所示的逆变单元1021,1031和1041;每个直流耦合单元还可以包括能源单元,如图1所示的能源单元1022,1032;每个直流耦合单元还可以包括储能单元,如图1所示的储能单元1033,1043。逆变单元1021,1031和1041的直流侧与直流母线105至107相连,交流侧与电网108相连,用于通过直流母线105至107接收能源单元1022,1032输出的电能,和/或,储能单元1033,1043放电的电能,以及对电能进行直流转交流变换之后,向电网108提供电能。逆变单元1021,1031和1041还可以用于吸收电网108的电能,以及对电能进行交流转直流变换后,通过直流母线105至107向储能单元1033,1043提供电能。能源单元1022,1032用于产生电能,储能单元1033,1043用于储存电能。
可选地,能源单元可以是新能源单元,例如,利用太阳能、地热能、风能、海洋能、生物质能或核聚变能等产生电能的电力装置。以下以利用太阳能产生电能的能源单元进行举例。
图2是本申请实施例提供的一种能源单元2000的结构示意图。该能源单元2000可以应用于图1所示的系统中。该能源单元可以包括至少一个光伏电池,如图2所示的光伏电池2100至2300;该能源单元还可以包括至少一个光伏控制器,如图2所示的光伏控制器2400至2600。光伏电池2100至2300通过光伏控制器2400至2600连接到直流母线上。其中,光伏电池2100至2300用于将太阳的光能直接转换为电能,例如单晶硅太阳能光伏电池、多晶硅太阳能光伏电池或非晶硅太阳能光伏电池;光伏控制器2400至2600用于分别控制光伏电池2100至2300,可选地,光伏控制器可以获取对应的光伏电池可提供的最大放电功率,例如光伏控制器可以是MPPT控制器。MPPT控制器能够实时跟踪光伏电池的最大的功率点,可以控制光伏电池以最大功率输出电能。
图3是本申请实施例提供的一种储能单元3000的结构示意图。该储能单元3000可以包括至少一个储能电池,如图3所示的储能电池3100至3300;该储能单元3000还可以包括至少一个储能控制器,如图3所示的储能控制器3400至3600。储能电池3100至3300 通过储能控制器3400至3600连接到直流母线上。其中,储能电池3100至3300可以用于存储电能,还可用于提供电能,例如,铅酸蓄电池,锂离子储能电池等;储能控制器3400至3600分别用于控制储能电池3100至3300,可以是一种DCDC控制器。
图4是本申请实施例提供的一种逆变单元4000的结构示意图。该逆变单元4000可以包括至少一个逆变器,如图4所示的逆变器4100至4300。其中,逆变器4100至4300的直流侧连接到直流母线上,逆变器4100至4300的交流侧连接到电网上,逆变器4100至4300上的功率方向可以是从直流母线流向电网,也可以是从电网吸收功率流向直流母线。
需要说明的是,本申请是以光伏系统进行举例,并不对本申请构成任何限定。
图1所示的电力系统既可以运用于电网调度功率上网的场景,也可以运用于电网调度从电网吸收功率的场景。
首先结合图5至图10对电网调度功率上网的场景进行说明。
需要说明的是,图5是一种为能源单元分配入网功率的方法100,图7是一种为储能单元分配入网功率的方法200,图9是一种为逆变单元分配第一逆变功率的方法300。方法100,方法200,以及方法300可以独立运用于电力系统中,也可以组合在一起运用于电力系统中。
例如,当方法100与方法200组合运用时,可以理解为运用方法100为直流耦合系统中的能源单元分配入网功率,若能源单元不能满足电网的调度需求的话,再运用方法200为直流耦合系统中的储能单元分配入网功率。
例如,当方法100与方法300组合运用时,可以理解为运用方法100为直流耦合系统中的能源单元分配入网功率,若能源单元可以满足电网的调度需求,则可以运用方法300为直流耦合系统的逆变单元分配第一逆变功率,从而可以实现将能源单元剩余的电能输送给储能单元进行储存。
图5是本申请实施例提供的一种为能源单元分配入网功率的方法100的示意性流程图。该方法100可以运用于电力系统,该电力系统包括N个直流耦合单元、N个直流母线以及总控制器。
为了清楚,以下举例将以太阳能转换成电能的光伏电力系统为例进行说明。
S110,总控制器获取电网的总入网需求功率。
该总入网需求功率是电网所需的入网功率。
S120,总控制器获取N个直流耦合单元的第一限幅值。
该第一限幅值用于指示N个直流耦合单元中每个直流耦合单元中的能源单元可向电网提供的最大放电功率。
S130,总控制器根据总入网需求功率和N个直流耦合单元的第一限幅值,确定N个直流耦合单元的第一入网功率值。
该第一入网功率值是指为N个直流耦合单元中每个直流耦合单元中的能源单元分配的输入电网的功率值,其中,N个直流耦合单元中的至少一个直流耦合单元处于第一限幅状态,第一限幅状态是指为直流耦合单元分配的第一入网功率值等于其对应的第一限幅值。
在一种可能的实现方式中,结合以下步骤S121至S123对图5中步骤S120中获取第一限幅值的方式进行说明。
S121,总控制器获取N个直流耦合单元的第一功率值。
该第一功率值为每个直流耦合单元中能源单元的最大放电功率。
在一种可能的实现方式中,在每个直流耦合单元中的能源单元中包括至少一个光伏电池和至少一个光伏控制器的情况下,总控制器可以从该至少一个光伏控制器中获取该至少一个光伏电池的最大放电功率。
其中,若光伏控制器为MPPT控制器,MPPT控制器可以向总控制器提供其对应的光伏电池的最大放电功率,其中,第j个直流耦合单元中的能源单元中的第i个光伏电池的最大放电功率为p
max_energy_ji。
需要说明的是,若MPPT控制器对应的光伏电池不处于MPPT点,该MPPT控制器向总控制器提供的最大放电功率值可以是MPPT控制器对其对应的光伏电池放电功率的估计值,若MPPT控制器对应的光伏电池处于降额状态,该MPPT控制器向总控制器提供的最大放电功率值可以是降额之后的最大放电功率。
总控制器根据该至少一个光伏电池的最大放电功率确定N个直流耦合单元中每个直流耦合单元中能源单元的最大放电功率,其中,第j个直流耦合单元中能源单元的最大放电功率,也就是第一功率值p
bus_max_energy_j为:
p
bus_max_energy_j=∑p
max_energy_ji (1)
也就是说,每个直流耦合单元中能源单元的最大放电功率为每个直流耦合单元中能源单元中的所有光伏控制器所提供的光伏电池的最大放电功率之和。
S122,总控制器获取N个直流耦合单元中每个直流耦合单元的第二功率值。
该第二功率值为每个直流耦合单元中逆变单元的最大放电功率。
在一种可能的实现方式中,在每个直流耦合单元中的逆变单元中包括至少一个逆变器的情况下,该总控制器获取每个逆变器的最大放电功率,其中,第j个直流耦合单元中的逆变单元中的第i个逆变器的最大放电功率为p
pcs_max_discharge_ji。
总控制器根据该至少一个逆变器的最大放电功率确定N个直流耦合单元中每个直流耦合单元中逆变单元的最大放电功率,其中,第j个直流耦合单元中逆变单元的最大放电功率,即第二功率值p
bus_max_pcs_discharge_j为:
p
bus_max_pcs_discharge_j=∑p
pcs_max_discharge_ji (2)
也就是说,每个直流耦合单元中逆变单元的最大放电功率为每个直流耦合单元中逆变单元中的所有逆变器的最大放电功率之和。
S123,总控制器根据N个直流耦合单元的第一功率值,以及N个直流耦合单元的第二功率值,确定N个直流耦合单元中每个直流耦合单元的第一限幅值。
在一种可能的实现方式中,总控制器将以下项中的最小值确定为每个直流耦合单元的第一限幅值:每个直流耦合单元的第一功率值、每个直流耦合单元的第二功率值。
也就是说,N个直流耦合单元中第j个直流耦合单元的第一限幅值p
lim_1_j为:
p
lim_1_j=min(p
bus_max_energy_j,p
bus_max_pcs_discharge_j) (3)
也就是说,直流耦合单元中的能源单元实际入网的功率需要受到逆变单元的限制,避免光伏电池、能源控制器或逆变器超幅运行,导致电力系统的可靠性下降。
在一种可能的实现方式中,结合图6对图5中的步骤S130中获取第一入网功率值的方式进行说明,图6示出了一种获取第一入网功率值的示意性流程图。
所述总控制器根据总入网需求功率和N个直流耦合单元的第一限幅值进行第一迭代 计算,以确定N个直流耦合单元的第一入网功率值。
S1301,总控制器计算N个直流耦合单元的初始第一候选入网功率值。
在一种可能的实现方式中,总控制器根据以下公式,确定N个直流耦合单元中每个直流耦合单元的初始第一候选功率值,其中第j个直流耦合单元的初始第一候选功率值为:
其中,p
bus_energy_to_grid_j表示N个直流耦合单元中第j个直流耦合单元的初始第一候选入网功率值,p
1表示总入网需求功率,p
bus_max_energy_j表示N个直流耦合单元中第j个直流耦合单元的第一功率值,
表示N个直流耦合单元的第一功率值之和,1≤j≤N。
S1302,总控制器在N个直流耦合单元中确定L个第二直流耦合单元。
在一种可能的实现方式中,第二直流耦合单元的初始第一候选入网功率值大于或等于其对应的第一限幅值,L为正整数。
需要说明的是,第二直流耦合单元可以理解为在本次计算后处于第一限幅状态的直流耦合单元。
S1303,总控制器根据该L个第二直流耦合单元进行判定。
在L=0的情况下,S1304,总控制器确定该N个直流耦合单元的第一入网功率值为其对应的初始第一候选入网功率值,并结束第一迭代计算。
也就是说,在L=0的情况下,在本次计算后N个直流耦合单元都未处于第一限幅状态,总控制器可以为该N个直流耦合单元中能源单元分配其对应的初始第一候选入网功率值进入电网。
在L=N的情况下,S1305,总控制器确定该L个第二直流耦合单元的第一入网功率值为其对应的第一限幅值,并结束第一迭代计算。
也就是说,在L=N的情况下,在本次计算后N个直流耦合单元全部处于第一限幅状态,总控制器为该N个直流耦合单元中能源单元分配其对应的第一限幅值进入电网。
在0<L<N的情况下,S1306,总控制器确定该L个第二直流耦合单元的第一入网功率值为其对应的第一限幅值。
总控制器先为该L个第二直流耦合单元分配第一入网功率值,再执行S1307。
S1307,总控制器确定L
1个第一直流耦合单元。
该L
1个第一直流耦合单元为在之前的第一迭代计算中未被分配第一入网功率值的直流耦合单元,L
1为正整数且L
1≤N。
需要说明的是,第一直流耦合单元也可以理解为在之前的第一迭代计算中计算获得的第一候选入网功率值小于其对应的第一限幅值。
S1308,总控制器确定参考入网需求功率。
在一种可能的实现方式中,根据以下公式,总控制器确定参考入网需求功率:
其中,p
ref_1为参考入网需求功率,
为已被分配第一入网功率值的直 流耦合单元的第一入网功率值之和,P
bus_energy_to_grid_j为已被分配第一入网功率值的直流耦合单元中第j个直流耦合单元的第一入网功率值。
S1309,计算L
1个第一直流耦合单元的第一候选入网功率值。
在一种可能的实现方式中,根据以下公式,总控制器确定该L
1个第一直流耦合单元的第一候选入网功率值:
其中,P
bus_energy_to_grid_j表示L
1个第一直流耦合单元中第j个第一直流耦合单元的第一候选入网功率值,p
bus_max_energy_j表示L
1个第一直流耦合单元中第j个第一直流耦合单元的第一功率值,
表示L
1个第一直流耦合单元的第一功率值之和,1≤j≤L
1。
S1310,总控制器在L
1个第一直流耦合单元中确定L
2个第二直流耦合单元。
其中,该L
2个第二直流耦合单元在S1309计算获得的第一候选入网功率值大于或等于其对应的第一限幅值,L
2为正整数。
S1311,总控制器确定该L
2个第二直流耦合单元的第一入网功率值。
该L
2个第二直流耦合单元处于第一限幅状态,也就是说,总控制器确定为该L
2个第二直流耦合单元分配其对应的第一限幅值进入电网。
S1312,总控制器根据该L
1个第一直流耦合单元和该L
2个第二直流耦合单元进行判定。
在L
1=L
2的情况下,S1313,总控制器确定结束该多轮第一迭代计算。
此时,之前未被分配的L
1个第一直流耦合单元在S1311中全部被分配其对应的第一限幅值作为第一入网功率值。
在L
1>L
2>0的情况下,回到S1307重新进行计算。
在L
2=0的情况下,S1314,总控制器确定该L
1个第一直流耦合单元的第一入网功率值,并结束该多轮第一迭代计算。
该L
1个第一直流耦合单元的第一入网功率值为对应的第一参考入网功率值。
此时,在本轮计算中,该L
1个第一直流耦合单元都未处于第一限幅状态,电网所需的入网功率被分配完。
从而,在本申请中,电力系统中的总控制器可以获取直流耦合单元中能源单元当前可向电网提供的最大放电功率,也就是第一限幅值,总控制器根据第一限幅值对总入网需求功率对每个直流耦合单元分配第一入网功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性。
图7是本申请实施例提供的一种为储能单元分配入网功率的方法200的示意性流程图。该方法200可以运用于电力系统,该电力系统包括N个直流耦合单元、N个直流母线以及总控制器。
为了清楚,以下举例将以太阳能转换成电能的光伏电力系统为例进行说明。
S210,总控制器获取电网的储能入网需求功率。
该储能入网需求功率是指需要储能单元为电网提供的入网功率。
S220,总控制器获取N个直流耦合单元的第二限幅值。
该第二限幅值用于指示每个直流耦合单元中的储能单元可向电网提供的最大放电功率。
S230,总控制器根据储能入网需求功率和N个直流耦合单元的第二限幅值,确定每个直流耦合单元的第二入网功率值。
该第二入网功率值是指为每个直流耦合单元中的储能单元分配的输入电网的功率值,其中,N个直流耦合单元中的至少一个直流耦合单元中的储能单元处于第二限幅状态,第二限幅状态是指为直流耦合单元分配的第二入网功率值等于其对应的第二限幅值。
在一种可能的实现方式中,结合以下步骤S211至S213对步骤S210中获取储能入网需求功率的方式进行说明。
S211,总控制器确定该N个直流耦合单元的总第一入网功率值。
该总第一入网功率值是指为N个直流耦合单元中能源单元分配的输入电网的总功率值。
总控制器可以确定该N个直流耦合单元中每个直流耦合单元的第一入网功率值,该总第一入网功率值为该N个直流耦合单元的第一入网功率值之和,其中,确定N个直流耦合单元中每个直流耦合单元的第一入网功率值可以与方法100描述的流程类似,在此不再赘述。
也就是说,总第一入网功率值p
energy_to_grid为:
p
energy_to_grid=∑p
bus_energy_to_grid_j (7)
其中P
bus_energy_to_grid_j为该N个直流耦合单元中第j个直流耦合单元的第一入网功率值。
S212,总控制器确定该N个直流耦合单元的总第一入网功率值是否满足电网的需求。
在总第一入网功率值小于总电网需求功率的情况下,总控制器确定该N个直流耦合单元的总第一入网功率值不满足电网的需求。
也就是说,当该N个直流耦合单元的能源单元无法满足电网的需求时,可以为该N个直流耦合单元中的储能单元分配入网的功率,从而满足电网的需求。
在总控制器确定该N个直流耦合单元的总第一入网功率值不满足电网的需求的情况下,S213,总控制器根据总第一入网功率值确定电网所需的储能入网需求功率。
该储能入网需求功率p
2为总电网需求功率p
1减去总第一入网功率值p
energy_to_grid的差值,即:
p
2=p
1-p
energy_to_grid (8)
在一种可能的实现方式中,结合以下步骤S221至S223对步骤S220中获取第二限幅值的方式进行说明。
S221,总控制器获取N个直流耦合单元中每个直流耦合单元的第二功率值。
该第二功率值为每个直流耦合单元中逆变单元的最大放电功率。
在每个直流耦合单元中的逆变单元中包括至少一个逆变器的情况下,总控制器获取第二功率值的方法可以与方法120中的S122类似,为了简便,在此不再赘述。
S222,总控制器获取N个直流耦合单元中每个直流耦合单元的第三功率值。
该第三功率值为每个直流耦合单元中的储能单元的最大放电功率。
在一种可能的实现方式中,在每个直流耦合单元中的储能单元包括至少一个储能电池和至少一个储能控制器的情况下,总控制器可以从该至少一个储能控制器中获取对应的储 能电池的最大放电功率,还可以获取每个储能控制器的最大放电功率。
总控制器根据该至少一个储能电池的最大放电功率和该至少一个储能控制器的最大放电功率确定每个直流耦合单元的第三功率值,其中,该N个直流耦合单元中的第j个直流耦合单元的第三功率值p
bus_max_bat_discharge_j为:
p
bus_max_bat_discharge_j=∑max(p
bat_max_discharge_ji,p
dcdc_max_discharge_ji) (9)
其中,p
bat_max_discharge_ji为第j个直流耦合单元中第i个储能电池的最大放电功率,p
dcdc_max_discharge_ji为第j个直流耦合单元中第i个储能控制器的最大放电功率,另外,可以定义负号为储能单元充电的方向,p
bat_max_discharge_ji与p
dcdc_max_discharge_ji皆为负值。
也就是说,储能电池与对应的储能控制器最终的最大放电功率为两者的最大放电功率的最大值,直流耦合单元中的储能单元的最大放电功率为该直流耦合单元中全部储能电池与对应的储能控制器最终的最大放电功率之和。
需要说明的是,一个储能控制器可以控制一个或多个储能电池,本申请对此不作限定。
S223,总控制器根据N个直流耦合单元中每个直流耦合单元的第二功率值和第三功率值确定每个直流耦合单元的第二限幅值。
在一种可能的实现方式中,总控制器将以下项中的最小值确定为每个直流耦合单元的第二限幅值:每个直流耦合单元的第二功率值、每个直流耦合单元的第三功率值。
也就是说,N个直流耦合单元中第j个直流耦合单元的第二限幅值p
lim_2_j为:
p
lim_2_j=min(p
bus_max_bat_discharge_j,p
bus_max_pcs_discharge_j) (10)
也就是说,直流耦合单元中的储能单元实际放电需要受到逆变单元的限制,避免储能电池、储能控制器或逆变器超幅运行,导致电力系统的可靠性下降。
在另一种可能的实现方式中,在该直流耦合单元还包括能源单元,且总控制器已经为该能源单元分配第一入网功率值的情况下,总控制器可以将以下项中的最小值确定为每个直流耦合单元的第二限幅值:每个直流耦合单元的第二功率值、每个直流耦合单元的剩余放电功率值,其中,剩余放电功率值为每个直流耦合单元的第二功率值减去第一入网功率值。
也就是说,N个直流耦合单元中第j个直流耦合单元的第二限幅值p
lim_2_j可以为:
p
lim_2_j=min(p
bus_max_bat_discharge_j,p
bus_max_pcs_discharge_j-p
bus_energy_to_grid_j) (11)
在这种情况下,由于逆变单元已经承受了能源单元的放电功率,所以在为储能单元分配输入电网的功率时需要考虑到已经为能源单元分配的输入电网的功率。
在一种可能的实现方式中,结合图8对图7中的步骤S230中获取第二入网功率值的方式进行说明,图8示出了一种获取第二入网功率值的示意性流程图。
总控制器根据储能入网需求功率和N个直流耦合单元的第二限幅值进行第二迭代计算,以确定N个直流耦合单元的第二入网功率值。
S2301,总控制器获取N个直流耦合单元的第一能量值。
该第一能量值为N个直流耦合单元中每个直流耦合单元中的储能单元当前存储的电能。
在一种可能的实现方式中,每个直流耦合单元中的储能单元中包括至少一个储能电池,总控制器可以获取每个直流耦合单元中的储能单元中的每一个储能电池当前存储的电能。
总控制器根据每一个储能电池当前存储的电能确定N个直流耦合单元中每个直流耦 合单元的第一能量值,其中第j个直流耦合单元的第一能量值SOE
bus_j为:
SOE
bus_j=∑SOE
ji (12)
其中,SOE
ji为第j个直流耦合单元中第i个储能电池当前存储的电能。
也就是说,一个直流耦合单元中中的储能单元可以包括多个储能电池,直流耦合单元的第一能量值为该直流耦合单元中全部储能电池当前存储的电能之和。
S2302,总控制器计算N个直流耦合单元的初始第二候选入网功率值。
在一种可能的实现方式中,总控制器根据以下公式,确定N个直流耦合单元中每个直流耦合单元的初始第二候选功率值,其中,第j个直流耦合单元的初始第二候选功率值为:
S2303,总控制器在N个直流耦合单元中确定M个第四直流耦合单元。
在一种可能的实现方式中,第四直流耦合单元的初始第二候选入网功率值大于或等于其对应的第二限幅值,M为正整数。
需要说明的是,第四直流耦合单元可以理解为在本次计算后处于第二限幅状态的直流耦合单元。
S2304,总控制器根据该M个第四直流耦合单元进行判定。
在M=0的情况下,S2305,总控制器确定该N个直流耦合单元的第二入网功率值为其对应的初始第二候选入网功率值,并结束第二迭代计算。
也就是说,在M=0的情况下,在本次计算后N个直流耦合单元都未处于第二限幅状态,总控制器可以为该N个直流耦合单元中储能单元分配其对应的初始第二候选入网功率值进入电网。
在M=N的情况下,S2306,总控制器确定该M个第四直流耦合单元的第二入网功率值为其对应的第二限幅值,并结束第二迭代计算。
也就是说,在M=N的情况下,在本次计算后N个直流耦合单元全部处于第二限幅状态,总控制器为该N个直流耦合单元中储能单元分配其对应的第二限幅值进入电网。
在0<M<N的情况下,S2307,总控制器确定该M个第四直流耦合单元的第二入网功率值为其对应的第二限幅值。
总控制器先为该M个第四直流耦合单元分配第二入网功率值,再执行S2308。
S2308,总控制器确定M
1个第三直流耦合单元。
该M
1个第三直流耦合单元为在之前的第二迭代计算中未被分配第二入网功率值的直流耦合单元,M
1为正整数且M
1≤N。
需要说明的是,第三直流耦合单元也可以理解为在之前的第二迭代计算中计算获得的第二候选入网功率值小于其对应的第二限幅值。
S2309,总控制器确定参考储能入网需求功率。
在一种可能的实现方式中,根据以下公式,总控制器确定参考储能入网需求功率:
其中,p
pref_2为参考储能入网需求功率,
为已被分配第二入网功率值的直流耦合单元的第二入网功率值之和,p
bus_bat_to_grid_j为已被分配第二入网功率值的直流耦合单元中第j个直流耦合单元的第二入网功率值。
S2310,总控制器计算M
1个第三直流耦合单元的第二候选入网功率值。
在一种可能的实现方式中,根据以下公式,总控制器确定该M
1个第三直流耦合单元的第二候选入网功率值:
其中,p
bus_bat_to_grid_j表示M
1个第三直流耦合单元中第j个第三直流耦合单元的第二候选入网功率值,p
pref_2表示参考储能入网需求功率,参考储能入网需求功率为储能入网需求功率减去在之前的第二迭代计算中已分配给直流耦合单元的第二入网功率值之和的差值,SOE
bus_j表示M
1个第三直流耦合单元中第j个第三直流耦合单元的第一能量值,
表示M
1个第三直流耦合单元的第一能量值之和,1≤j≤M
1。
S2311,总控制器在M
1个第三直流耦合单元中确定M
2个第四直流耦合单元。
其中,该M
2个第四直流耦合单元在S2310计算获得的第二候选入网功率值大于或等于其对应的第二限幅值,M
2为正整数。
S2312,总控制器确定该M
2个第四直流耦合单元的第二入网功率值。
该M
2个第四直流耦合单元处于第二限幅状态,也就是说,总控制器确定为该M
2个第四直流耦合单元分配其对应的第二限幅值进入电网。
S2313,总控制器根据该M
1个第三直流耦合单元和该M
2个第四直流耦合单元进行判定。
在M
1=M
2的情况下,S2314,总控制器确定结束该多轮第二迭代计算。
此时,之前未被分配的M
1个第三直流耦合单元在S2312中全部被分配其对应的第二限幅值作为第二入网功率值。
在M
1>M
2>0的情况下,回到S2308重新进行计算。
在M
2=0的情况下,S2315,总控制器确定该M
1个第三直流耦合单元的第二入网功率值,并结束该多轮第二迭代计算。
该M
1个第三直流耦合单元的第二入网功率值为对应的第二候选入网功率值。
此时,在本轮计算中,该M
1个第三直流耦合单元都未处于第二限幅状态,储能单元需要入网的功率被分配完。
从而,在本申请中,电力系统中的总控制器可以获取直流耦合单元中储能单元当前可向电网提供的最大放电功率,也就是第二限幅值,总控制器根据第二限幅值对储能入网需求功率对每个直流耦合单元分配第二入网功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性,并且,电力系统中的储能单元可以均衡放电,提高储能单元中电力器件的生命周期。
图9是本申请实施例提供的一种为逆变单元分配第一逆变功率的方法300的示意性流 程图。该方法300可以运用于电力系统,该电力系统包括N个直流耦合单元、N个直流母线以及总控制器。
为了清楚,以下举例将以太阳能转换成电能的光伏电力系统为例进行说明。
S310,总控制器获取N个直流耦合单元的放电需求功率。
所述放电需求功率用于指示为每个直流耦合单元中的能源单元分配的给N个直流耦合单元的储能单元充电的功率。
S320,总控制器获取N个直流耦合单元的充电需求功率。
所述充电需求功率用于指示为每个直流耦合单元中的储能单元分配的从N个直流耦合单元的能源单元获取的功率。
S330,总控制器根据所述N个直流耦合单元的放电需求功率和所述N个直流耦合单元的充电需求功率确定每个直流耦合单元的第一逆变功率值。
所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元向电网提供电能的功率,或所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元从电网吸收电能的功率。
在一种可能的实现方式中,结合以下步骤S311至S319对步骤S310中获取每个直流耦合单元的放电需求功率的方式进行说明。
S311,总控制器获取N个直流耦合单元中每个直流耦合单元的第一功率值。
该第一功率值为每个直流耦合单元中能源单元的最大放电功率。
总控制器获取第一功率值的方式可以与方法100中的S121中描述的方式类似,为了简便,在此不再赘述。
S312,总控制器获取该N个直流耦合单元的总第一入网功率值。
该总第一入网功率值是指为N个直流耦合单元中能源单元分配的输入电网的总功率值。
总控制器可以确定该N个直流耦合单元中每个直流耦合单元的第一入网功率值,该总第一入网功率值为该N个直流耦合单元的第一入网功率值之和,其中,确定N个直流耦合单元中每个直流耦合单元的第一入网功率值可以与方法100描述的流程类似,在此不再赘述。
也就是说,总第一入网功率值P
energy_to_grid为:
P
energy_to_grid=∑P
bus_energy_to_grid_j (16)
其中P
bus_energy_to_grid_j为该N个直流耦合单元中第j个直流耦合单元的第一入网功率值。
S313,总控制器获取该N个直流耦合单元中每个直流耦合单元的第三功率值。
该第三功率值为每个直流耦合单元中的储能单元的最大放电功率。
总控制器获取第三功率值的方式可以与方法200中的S222中描述的方式类似,为了简便,在此不再赘述。
S314,总控制器确定该N个直流耦合单元的总第一入网功率值是否满足电网的需求。
在总第一入网功率值等于总电网需求功率的情况下,总控制器确定该N个直流耦合单元的总第一入网功率值满足电网的需求。
也就是说,当该N个直流耦合单元的能源单元满足电网的需求时,可以将N个直流耦合单元中的能源单元剩余的功率分配给N个直流耦合单元中的储能单元进行储存,从而 提高了新能源电能的利用率。
在总控制器确定该N个直流耦合单元的总第一入网功率值满足电网的需求的情况下,总控制器可以根据总第一入网功率值确定总充电需求功率。
该总充电需求功率是为N个直流耦合单元中的储能单元分配的从N个直流耦合单元中的能源单元获取的总功率。
在一种可能的方式中,S315,总控制器确定N个直流耦合单元的第一充电能力值。
该第一充电能力值为N个直流耦合单元中的能源单元可提供给储能单元电能的能力值。
总控制器可以根据下式确定N个直流耦合单元中能源单元给储能单元的第一充电能力值p
max_energy_to_bat_1为:
也就是说,在N个直流耦合单元中能源单元已经给电网提供第一入网功率值的情况下,第一充电能力值为N个直流耦合单元中能源单元还剩余的可以放电的功率值。
S316,总控制器获取N个直流耦合单元中每个直流耦合单元中储能单元的最大充电功率。
在一种可能的实现方式中,在每个直流耦合单元中的储能单元包括至少一个储能电池和至少一个储能控制器的情况下,总控制器可以从该至少一个储能控制器中获取对应的储能电池的最大充电功率,还可以获取每个储能控制器的最大充电功率。
总控制器根据该至少一个储能电池的最大充电功率和该至少一个储能控制器的最大充电功率确定每个直流耦合单元中储能单元的最大充电功率,其中,该N个直流耦合单元中的第j个直流耦合单元中储能单元的最大充电功率P
bus_max_bat_charge_j为:
p
bat_max_charge_j=∑min(p
bat_max_charge_ji,p
dcdc_max_charge_ji) (18)
其中,P
bat_max_charge_ji为第j个直流耦合单元中第i个储能电池的最大充电功率,P
dcdc_max_charge_ji为第j个直流耦合单元中第i个储能控制器的最大充电功率。
也就是说,储能电池与对应的储能控制器最终的最大充电功率为储能电池与对应的储能控制器的最大充电功率的最小值,直流耦合单元中的储能单元的最大充电功率为该直流耦合单元中全部储能电池与对应的储能控制器最终的最大充电功率之和。
需要说明的是,一个储能控制器可以控制一个或多个储能电池,本申请对此不作限定。
S317,总控制器确定N个直流耦合单元的第二充电能力值。
该第二充电能力值为N个直流耦合单元中的储能单元可接受的电能的能力值。
在一种可能的实现方式中,总控制器可以根据下式获取第二充电能力值为p
max_bat_charge:
也就是说,N个直流耦合单元的第二充电能力值为该N个直流耦合单元中每个直流耦合单元中储能单元的最大充电功率值之和。
S318,总控制器获取总充电需求功率。
总充电需求功率是为N个直流耦合单元中的储能单元分配的从N个直流耦合单元中的能源单元获取的总功率;
在一种可能的实现方式中,总控制器可以根据以下公式确定总充电需求功率:
p
max_energy_to_bat=min(p
max_bat_charge,p
max_energy_to_bat_1) (20)
也就是说,总控制器可以确定第一充电能力值和第二充电能力值中的最小值作为总充电需求功率。
S319,总控制器获取N个直流耦合单元中每个直流耦合单元的放电需求功率。
在一种可能的方式中,总控制器可以根据下式确定N个直流耦合单元中每个直流耦合单元的放电需求功率,其中,第j个直流耦合单元的放电需求功率p
bus_energy_to_bat_j为:
也就是说,N个直流耦合单元中每个直流耦合单元的放电需求功率可以根据每个直流耦合单元的第一功率值,即直流耦合单元中能源单元的最大放电功率值占N个直流耦合单元的第一功率值之和的占比来分配总充电需求功率,从而获得为每个直流耦合单元中能源单元分配的用于储存的功率。
在一种可能的实现方式中,结合图10对图9中的步骤S320中获取每个直流耦合单元的充电需求功率的方式进行说明,图10示出了一种获取充电需求功率的示意性流程图。
总控制器可以进行第三迭代计算,以确定N个直流耦合单元中每个直流耦合单元的充电需求功率。
S3201,总控制器获取N个直流耦合单元的第三限幅值。
该第三限幅值用于指示N个直流耦合单元中每个直流耦合单元中储能单元可提供的最大充电功率。
在一种可能的实现方式中,每个直流耦合单元的第三限幅值可以是每个储能单元的最大充电功率。
S3202,总控制器获取N个直流耦合单元中每个直流耦合单元的第二能量值。
该第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差。
其中,总控制器可以从储能单元获取每个直流耦合单元中的储能单元的可提供的电能值总量,也可以在总控制器中预配置每个直流耦合单元中的储能单元的可提供的电能值总量。
需要说明的是,每个直流耦合单元中的储能单元的已存储的电能值可以理解为方法200中的第一能量值,即N个直流耦合单元中每个直流耦合单元中的储能单元当前存储的电能。因此,其获取方式可以与方法200中的步骤S2301的获取方式类似,为了简便,在此不再赘述。
S3203,总控制器计算N个直流耦合单元的初始候选充电需求功率。
在一种可能的实现方式中,总控制器根据以下公式,确定N个直流耦合单元中每个直流耦合单元的初始候选充电需求功率,其中,第j个直流耦合单元的初始候选充电需求功率为:
其中,p
bus_bat_charge_j表示N个直流耦合单元中第j个直流耦合单元的初始候选充电需求功率,SOE
bus_able_j表示N个直流耦合单元中第j个直流耦合单元的第二能量值,
为N个直流耦合单元的第二能量值之和,1≤j≤N。
S3204,总控制器在N个直流耦合单元中确定T个第六直流耦合单元。
在一种可能的实现方式中,第六直流耦合单元的初始候选充电需求功率大于或等于其对应的第三限幅值,T为正整数。
需要说明的是,第六直流耦合单元可以理解为在本次计算后处于第三限幅状态的直流耦合单元。
S3205,总控制器根据该T个第六直流耦合单元进行判定。
在T=0的情况下,S3206,总控制器确定该N个直流耦合单元的充电需求功率为其对应的初始候选充电需求功率,并结束第三迭代计算。
也就是说,在T=0的情况下,在本次计算后N个直流耦合单元都未处于第三限幅状态,总控制器可以确定该N个直流耦合单元的充电需求功率为其对应的初始候选充电需求功率。
在T=N的情况下,S3207,总控制器确定该T个第六直流耦合单元的充电需求功率为其对应的第三限幅值,并结束第三迭代计算。
也就是说,在T=N的情况下,在本次计算后N个直流耦合单元全部处于第三限幅状态,总控制器可以确定该N个直流耦合单元的充电需求功率为其对应的第三限幅值。
在0<T<N的情况下,S3208,总控制器确定该T个第六直流耦合单元的充电需求功率为其对应的第三限幅值。
总控制器先为该T个第六直流耦合单元分配充电需求功率,再执行S3209。
S3209,总控制器确定T
1个第五直流耦合单元。
该T
1个第五直流耦合单元为在之前的第三迭代计算中未被分配充电需求功率的直流耦合单元,T
1为正整数且T
1≤N。
需要说明的是,第五直流耦合单元也可以理解为在之前的第三迭代计算中计算获得的候选充电需求功率小于其对应的第三限幅值。
S3210,总控制器确定参考总充电需求功率。
在一种可能的实现方式中,根据以下公式,总控制器确定参考总充电需求功率:
其中,p
pref_3为参考总充电需求功率,
为已被分配充电需求功率的直流耦合单元的充电需求功率之和,p
bus_bat_charge_j为已被分配充电需求功率的直流耦合单元中第j个直流耦合单元的充电需求功率。
S3211,总控制器计算T
1个第五直流耦合单元的候选充电需求功率。
在一种可能的实现方式中,根据以下公式,总控制器确定该T
1个第五直流耦合单元的候选充电需求功率:
其中,p
bus_bat_charge_j表示所述T
1个第五直流耦合单元中第j个第五直流耦合单元的选充电需求功率,p
pref_3表示参考总充电需求功率,SOE
bus_able_j表示所述T
1个第五直流耦合单元中第j个第五直流耦合单元的第二能量值,
表示所述T
1个第五直流耦合单元的第二能量值之和,1≤j≤T
1。
S3212,总控制器在T
1个第五直流耦合单元中确定T
2个第六直流耦合单元。
其中,该T
2个第六直流耦合单元在S3211计算获得的候选充电需求功率大于或等于其对应的第三限幅值,T
2为正整数。
S3213,总控制器确定该T
2个第六直流耦合单元的充电需求功率。
该T
2个第六直流耦合单元处于第三限幅状态,也就是说,总控制器确定该T
2个第六直流耦合单元的充电需求功率为其对应的第三限幅值。
S3214,总控制器根据该T
1个第五直流耦合单元和该T
2个第六直流耦合单元进行判定。
在T
1=T
2的情况下,S3215,总控制器确定结束该多轮第三迭代计算。
此时,之前未被分配的T
1个第五直流耦合单元在S3213中全部被分配其对应的第三限幅值作为充电需求功率。
在T
1>T
2>0的情况下,回到S3209重新进行计算。
在T
2=0的情况下,S3216,总控制器确定该T
1个第五直流耦合单元的充电需求功率,并结束该多轮第三迭代计算。
该T
1个第五直流耦合单元的充电需求功率为对应的参考充电需求功率。
此时,在本轮计算中,该T
1个第五直流耦合单元都未处于第三限幅状态,总充电需求功率被分配完。
也就是说,经过第三迭代计算,总控制器可以确定N个直流耦合单元的充电需求功率。
在一种可能的实现方式中,结合以下步骤S3301至S3309对图9中步骤S330中获取第一逆变功率值的方式进行说明。
S3301,总控制器确定N个直流耦合单元中每个直流耦合单元的交换功率。
该交换功率为N个直流耦合单元中每个直流耦合单元的放电需求功率减去其对应的充电需求功率。
也就是说,N个直流耦合单元中第j个直流耦合单元的交换功率p
bus_pcs_to_other_j为:
p
bus_pcs_to_other_j=p
bus_energy_to_bat_j-p
bus_bat_charge_j (25)
S3302,总控制器根据N个直流耦合单元的第一候选逆变功率。
在一种可能的实现方式中,在存在直流耦合单元中的能源单元已被分配输入电网的功率值,也就是第一入网功率值的情况下,N个直流耦合单元中每个直流耦合单元的第一候选逆变功率为每个直流耦合单元的交换功率与对应的第一入网功率值之和,N个直流耦合单元中的第j个直流耦合单元的第一候选逆变功率值p
bus_pcs_to_grid_j_1为:
p
bus_pcs_to_grid_j_1=p
bus_pcs_to_other_j+p
bus_energy_to_grid_j (26)
也就是说,直流耦合单元中的逆变单元需要承受同一个直流耦合单元中的能源单元输 出的功率值,因此,逆变单元上实际承载的逆变功率,与同一个直流耦合单元中的能源单元输入电网的功率、能源单元给储能单元充电的功率,以及同一个直流耦合单元中的能源单元充电的功率相关。
S3303,总控制器获取N个直流耦合单元中每个直流耦合单元的第二功率值。
该第二功率值为每个直流耦合单元中逆变单元的最大放电功率。
在每个直流耦合单元中的逆变单元中包括至少一个逆变器的情况下,总控制器获取第二功率值的方法可以与方法120中的S122类似。
S3304,总控制器确定放电调整需求值。
该放电调整需求值为N个直流耦合单元中第一候选逆变功率值大于0,且第一候选逆变功率值大于对应的第二功率值的直流耦合单元的第一候选逆变功率值减去对应的第二功率值的差值之和。
也就是说,放电调整需求值Delta_pos_sum为:
需要说明的是,直流耦合单元的第一候选逆变功率值大于0,可以理解为该直流耦合单元的逆变单元处于放电状态,可以考虑该直流耦合单元的第一候选逆变功率值是否超过了逆变单元的最大放电功率值,如果超过了的话,则表明该直流耦合单元不可以承受第一候选逆变功率,该逆变单元被限幅,放电调整需求值就是N个直流耦合单元中逆变单元被限幅的直流耦合单元超过第二功率值的总和。
S3305,总控制器确定充电调整需求值。
该充电调整需求值为所述N个直流耦合单元中第一候选逆变功率值小于0,且第一候选逆变功率值小于对应的第四功率值的直流耦合单元的第四功率值减去对应的第一候选逆变功率值的差值之和。
该第四功率值为每个直流耦合单元中逆变单元的最大充电功率。
在一种可能的实现方式中,在每个直流耦合单元中的逆变单元中包括至少一个逆变器的情况下,该总控制器获取每个逆变器的最大充电功率,其中,第j个直流耦合单元中的逆变单元中的第i个逆变器的最大充电功率为p
pcs_max_charge_ji。
总控制器根据该至少一个逆变器的最大充电功率确定N个直流耦合单元中每个直流耦合单元中逆变单元的最大充电功率,其中,第j个直流耦合单元中逆变单元的最大充电功率,即第四功率值p
bus_max_pcs_charge_j为:p
bus_max_pcs_charge_j=∑p
pcs_max_charge_ji。
也就是说,每个直流耦合单元中逆变单元的最大充电功率为每个直流耦合单元中逆变单元中的所有逆变器的最大充电功率之和。
也就是说充电调整需求值Delta_neg_sum为:
其中,第一候选逆变功率值和第四功率值的负号代表功率方向为充电方向,充电方向可以理解为从电网经过逆变单元到储能单元的方向,其绝对值代表功率值的大小。
需要说明的是,直流耦合单元的第一候选逆变功率值小于0,可以理解为该直流耦合单元的逆变单元处于充电状态,可以考虑该直流耦合单元的第一候选逆变功率值的绝对值 是否超过了逆变单元的最大充电功率值,如果超过了的话,则表明该直流耦合单元不可以承受第一候选逆变功率,该逆变单元被限幅,放电调整需求值就是N个直流耦合单元中逆变单元被限幅的直流耦合单元超过第四功率值的总和。
S3306,总控制器确定调整需求功率。
该调整需求功率为所述放电调整需求值减去所述充电调整需求值的差值的绝对值。
也就是说,调整需求功率Delta为:
Delta=|Delta_pos_max-Delta_neg_max| (29)
S3307,总控制器获取N个直流耦合单元中每个直流耦合单元的调整比例值。
该调整比例值为每个直流耦合单元的交换功率值占交换功率值大于0的直流耦合单元的交换功率值之和的占比。
也就是说,N个直流耦合单元中第j个直流耦合单元的调整比例值为:
其中,
S3308,总控制器确定N个直流耦合单元中每个直流耦合单元的第二候选逆变功率值。
其中,第一候选逆变功率值大于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第二功率值中的最小值,第一候选逆变功率值小于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第四功率值中的最大值。
也就是说:
若p
bus_pcs_to_grid_j_1>0
p
bus_pcs_to_grid_j_2=min(p
bus_pcs_to_grid_j_1,p
bus_max_pcs_discharge_j) (32)
若p
bus_pcs_to_grid_j_1<0
p
bus_pcs_to_grid_j_2=max(p
bus_pcs_to_grid_j_1,p
bus_max_pcs_charge_j) (33)
其中,p
bus_pcs_to_grid_j_2为N个直流耦合单元中第j个直流耦合单元的第二候选逆变功率值,p
bus_pcs_to_grid_j_1为N个直流耦合单元中第j个直流耦合单元的第一候选逆变功率值,p
bus_max_pcs_discharge_j为N个直流耦合单元中第j个直流耦合单元的第二功率值,p
bus_max_pcs_charge_j为N个直流耦合单元中第j个直流耦合单元的第四功率值。
S3309,总控制器在确定放电需求功率大于充电需求功率的情况下,确定交换功率值小于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值减去调整需求功率与对应的调整比例值乘积的差值,确定交换功率大于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值。
也就是说,
若Delta_pos_max>Delta_neg_max,
p
bus_pcs_to_other_j<0的直流耦合单元的第一逆变功率值为:
p
bus_pcs_to_grid_j=p
bus_pcs_to_grid_j_2-Delta*K
bus_j (34)
p
bus_pcs_to_other_j>0的直流耦合单元的第一逆变功率值为:
p
bus_pcs_to_grid_j=p
bus_pcs_to_grid_j_2 (35)
若Delta_pos_max<Delta_neg_max,
p
bus_pcs_to_other_j<0的直流耦合单元的第一逆变功率值为:
p
bus_pcs_to_grid_j=p
bus_pcs_to_grid_j_2 (36)
p
bus_pcs_to_other_j>0的直流耦合单元的第一逆变功率值为:
p
bus_pcs_to_grid_j=p
bus_pcs_to_grid_j_2-Delta*K
bus_j (37)
在一种可能的实现方式中,若直流耦合单元中的逆变单元包括多个逆变器,则可以根据每个逆变器的最大放电功率占第二功率值的占比分配第一逆变功率值,或根据每个逆变器的最大充电功率占第四功率值的占比分配第一逆变功率值。
例如,若p
bus_pcs_to_grid_j>0,
若p
bus_pcs_to_grid_j<0,
其中,p
pcs_to_grid_ji表示第j个直流耦合单元中的逆变单元中的第i个逆变器的逆变功率,p
pcs_max_discharge_ji表示第j个直流耦合单元中的逆变单元中的第i个逆变器的最大放电功率,p
pcs_max_charge_ji表示第j个直流耦合单元中的逆变单元中的第i个逆变器的最大充电功率。
从而,在本申请中,可以通过确定N个直流耦合单元中逆变单元的第一逆变功率值,实现将直流耦合单元的能源单元产生的电能给该直流耦合单元和/或其它直流耦合单元的储能单元充电,从而可以减少能源单元的电能浪费。
以下结合图11和图13对电网调度从电网吸收功率的场景进行说明。
需要说明的是,图11是一种为储能单元分配吸收功率的方法400,图13是一种为逆变单元分配第一逆变功率的方法500。方法400和方法500可以独立运用于电力系统中,也可以组合在一起运用在电力系统中。
例如,当方法400和方法500组合运用时,可以理解为运用方法400为直流耦合系统的储能单元分配吸收功率,若储能单元能够满足电网的调度需求,则可以运用方法500为直流耦合系统的逆变单元分配第一逆变功率,从而可以实现让储能单元剩余的容量存储能源单元发出的电能。
图11是本申请实施例提供的一种为储能单元分配吸收功率的方法400的示意性流程图。该方法400可以运用于电力系统,该电力系统包括N个直流耦合单元、N个直流母线以及总控制器。
为了清楚,以下举例将以太阳能转换成电能的光伏电力系统为例进行说明。
S410,总控制器获取所述电网的吸收需求功率。
该吸收需求功率为所述N个直流耦合单元中储能单元需要从电网吸收的功率。
S420,总控制器获取所述N个直流耦合单元的第四限幅值。
该第四限幅值用于指示每个直流耦合单元可提供的最大充电功率。
S430,总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值。
该吸收功率值是指为每个直流耦合单元中的能源单元分配的从电网吸收的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元处于第四限幅状态,所述第四限幅状态是指为直流耦合单元分配的吸收功率值等于其对应的第四限幅值。
在一种可能的实现方式中,结合以下步骤S421至S423对图11中步骤S420中获取第四限幅值的方式进行说明。
S421,总控制器获取N个直流耦合单元中每个直流耦合单元的第四功率值的绝对值。
该第四功率值为每个直流耦合单元中逆变单元的最大充电功率。
在一种可能的实现方式中,在每个直流耦合单元中的逆变单元中包括至少一个逆变器的情况下,该总控制器获取每个逆变器的最大充电功率,其中,第j个直流耦合单元中的逆变单元中的第i个逆变器的最大充电功率为P
pcs_max_charge_ji。
总控制器根据该至少一个逆变器的最大充电功率确定N个直流耦合单元中每个直流耦合单元中逆变单元的最大充电功率,其中,第j个直流耦合单元中逆变单元的最大充电功率,即第四功率值P
bus_max_pcs_charge_j为:
P
bus_max_pcs_charge_j=∑P
pcs_max_charge_ji (40)
也就是说,每个直流耦合单元中逆变单元的最大充电功率为每个直流耦合单元中逆变单元中的所有逆变器的最大充电功率之和。
S422,总控制器获取N个直流耦合单元中每个直流耦合单元的第五功率值。
该第五功率值为每个直流耦合单元中储能单元的最大充电功率。
在一种可能的实现方式中,在每个直流耦合单元中的储能单元包括至少一个储能电池和至少一个储能控制器的情况下,总控制器可以从该至少一个储能控制器中获取对应的储能电池的最大充电功率,还可以获取每个储能控制器的最大充电功率。
总控制器根据该至少一个储能电池的最大充电功率和该至少一个储能控制器的最大充电功率确定每个直流耦合单元的第五功率值,其中,该N个直流耦合单元中的第j个直流耦合单元的第五功率值P
bus_max_bat_charge_j为:
P
bus_max_bat_charge_j=∑min(P
bat_max_charge_ji,P
dcdc_max_charge_ji) (41)
其中,P
bat_max_charge_ji为第j个直流耦合单元中第i个储能电池的最大充电功率,P
dcdc_max_charge_ji为第j个直流耦合单元中第i个储能控制器的最大充电功率。
也就是说,储能电池与对应的储能控制器最终的最大充电功率为两者的最大充电功率的最小值,直流耦合单元中的储能单元的最大充电功率为该直流耦合单元中全部储能电池与对应的储能控制器最终的最大充电功率之和。
需要说明的是,一个储能控制器可以控制一个或多个储能电池,本申请对此不作限定。
S423,总控制器获取N个直流耦合单元第四限幅值。
例如,总控制器将以下项中的最小值确定为每个直流耦合单元的第四限幅值:每个直流耦合单元的第四功率值的绝对值,每个直流耦合单元的第五功率值。
也就是说,N个直流耦合单元中第j个直流耦合单元的第四限幅值P
lim_4_j为:
P
lim_4_j=min(P
bus_max_bat_charge_j,P
bus_max_pcs_charge_j) (42)
也就是说,直流耦合单元中的储能单元实际充电的功率需要受到逆变单元的限制,避 免储能电池、储能控制器或逆变器超幅运行,导致电力系统的可靠性下降。
在一种可能的实现方式中,结合图12对图11中的步骤S430中获取吸收功率值的方式进行说明,图12示出了一种获取吸收功率值的示意性流程图。
S4301,总控制器获取N个直流耦合单元的第二能量值。
该第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差。
该第一能量值为N个直流耦合单元中每个直流耦合单元中的储能单元当前存储的电能。
在一种可能的实现方式中,总控制器可以获取N个直流耦合单元已存储的电能值,定义N个直流耦合单元中每个直流耦合单元中已存储的电能,或者说是当前存储的电能为第一能量值。
若每个直流耦合单元中的储能单元中包括至少一个储能电池,总控制器可以获取每个直流耦合单元中的储能单元中的每一个储能电池当前存储的电能。
总控制器根据每一个储能电池当前存储的电能确定N个直流耦合单元中每个直流耦合单元的第一能量值,其中第j个直流耦合单元的第一能量值SOE
bus_j为:
SOE
bus_j=∑SOE
ji (43)
其中,SOE
ji为第j个直流耦合单元中第i个储能电池当前存储的电能。
也就是说,一个直流耦合单元中中的储能单元可以包括多个储能电池,直流耦合单元的第一能量值为该直流耦合单元中全部储能电池当前存储的电能之和。
可选地,可以从储能单元获取每个直流耦合单元中的储能单元的可提供的电能值总量,也可以在总控制器中预配置每个直流耦合单元中的储能单元的可提供的电能值总量。
也就是说,N个直流耦合单元中第j个直流耦合单元的第二能量值SOE
bus_able_j为:
SOE
bus_able_j=SOE
bus_full_j-SOE
bus_j (44)
其中,SOE
bus_full_j为第j个直流耦合单元的可存储的电能值总量,SOE
bus_j为第j个直流耦合单元的已存储的电能值。
S4302,总控制器计算N个直流耦合单元的初始候选吸收功率值。
在一种可能的实现方式中,总控制器根据以下公式,确定N个直流耦合单元中每个直流耦合单元的初始候选吸收功率值,其中,第j个直流耦合单元的初始候选吸收功率值为:
其中,p
absorb为吸收需求功率,p
bus_bat_from_grid_j表示N个直流耦合单元中第j个直流耦合单元的初始候选吸收功率值,SOE
bus_able_j表示N个直流耦合单元中第j个直流耦合单元的第二能量值,
为N个直流耦合单元的第二能量值之和,1≤j≤N。
S4303,总控制器在N个直流耦合单元中确定Q个第八直流耦合单元。
在一种可能的实现方式中,第八直流耦合单元的初始候选吸收功率值大于或等于其对应的第四限幅值,Q为正整数。
需要说明的是,第八直流耦合单元可以理解为在本次计算后处于第四限幅状态的直流耦合单元。
S4304,总控制器根据该Q个第八直流耦合单元进行判定。
在Q=0的情况下,S4305,总控制器确定该N个直流耦合单元的吸收功率值为其对应的初始候选吸收功率值,并结束第四迭代计算。
也就是说,在Q=0的情况下,在本次计算后N个直流耦合单元都未处于第四限幅状态,总控制器可以确定该N个直流耦合单元的吸收功率值为其对应的初始候选吸收功率值。
在Q=N的情况下,S4306,总控制器确定该Q个第八直流耦合单元的吸收功率值为其对应的第四限幅值,并结束第四迭代计算。
也就是说,在Q=N的情况下,在本次计算后N个直流耦合单元全部处于第四限幅状态,总控制器可以确定该N个直流耦合单元的吸收功率值为其对应的第四限幅值。
在0<Q<N的情况下,S4307,总控制器确定该Q个第八直流耦合单元的吸收功率值为其对应的第四限幅值。
总控制器先为该Q个第八直流耦合单元分配吸收功率值,再执行S4308。
S4308,总控制器确定Q
1个第七直流耦合单元。
该Q
1个第七直流耦合单元为在之前的第四迭代计算中未被分配吸收功率值的直流耦合单元,Q
1为正整数且Q
1≤N。
需要说明的是,第七直流耦合单元也可以理解为在之前的第四迭代计算中计算获得的候选吸收功率值小于其对应的第四限幅值。
S4309,总控制器确定参考吸收需求功率值。
在一种可能的实现方式中,根据以下公式,总控制器确定参考吸收需求功率值:
其中,p
pref_absorb为参考吸收需求功率值,
为已被分配吸收功率值的直流耦合单元的吸收功率值之和,p
bus_bat_from_grid_j为已被分配吸收功率值的直流耦合单元中第j个直流耦合单元的吸收功率值。
S4310,总控制器计算Q
1个第七直流耦合单元的候选吸收功率值。
在一种可能的实现方式中,根据以下公式,总控制器确定该Q
1个第七直流耦合单元的候选吸收功率值:
其中,p
bus_bat_from_grid_j表示所述Q
1个第七直流耦合单元中第j个第七直流耦合单元的第一候选吸收功率值,p
ref_absorb表示参考吸收需求功率值,SOE
bus_able_j表示所述Q
1个第七直流耦合单元中第j个第七直流耦合单元的第二能量值,
表示所述Q
1个第七直流耦合单元的第二能量值之和,1≤j≤Q
1。
S4311,总控制器在Q
1个第七直流耦合单元中确定Q
2个第八直流耦合单元。
其中,该Q
2个第八直流耦合单元在S4310计算获得的候选吸收功率值大于或等于其对应的第四限幅值,Q
2为正整数。
S4312,总控制器确定该Q
2个第八直流耦合单元的吸收功率值。
该Q
2个第八直流耦合单元处于第四限幅状态,也就是说,总控制器确定该Q
2个第八 直流耦合单元的吸收功率值为其对应的第四限幅值。
S4313,总控制器根据该Q
1个第七直流耦合单元和该Q
2个第八直流耦合单元进行判定。
在Q
1=Q
2的情况下,S4314,总控制器确定结束该多轮第四迭代计算。
此时,之前未被分配的Q
1个第七直流耦合单元在S4312中全部被分配其对应的第四限幅值作为吸收功率值。
在Q
1>Q
2>0的情况下,回到S4308重新进行计算。
在Q
2=0的情况下,S4315,总控制器确定该Q
1个第七直流耦合单元的吸收功率值,并结束该多轮第四迭代计算。
该Q
1个第七直流耦合单元的吸收功率值为对应的候选吸收功率值。
此时,在本轮计算中,该Q
1个第七直流耦合单元都未处于第四限幅状态,吸收需求功率被分配完。
也就是说,经过第四迭代计算,总控制器可以确定N个直流耦合单元的吸收功率值。
从而,在本申请中,电力系统中的总控制器可以获取每个直流耦合单元可提供的最大充电功率,也就是直流耦合单元中储能单元当前可从电网吸收的最大充电功率,也就是第四限幅值,总控制器根据第四限幅值对吸收需求功率值对每个直流耦合单元分配吸收功率值,可以避免电力系统中的电力器件因超过限幅而造成电力系统运行的可靠性下降,从而可以提高电力系统运行的可靠性。
图13是本申请实施例提供的一种为逆变单元分配第一逆变功率的方法500的示意性流程图。该方法500可以运用于电力系统,该电力系统包括N个直流耦合单元、N个直流母线以及总控制器。
为了清楚,以下举例将以太阳能转换成电能的光伏电力系统为例进行说明。
S510,总控制器获取N个直流耦合单元的放电需求功率。
所述放电需求功率用于指示为每个直流耦合单元中的能源单元分配的给N个直流耦合单元的储能单元充电的功率。
S520,总控制器获取N个直流耦合单元的充电需求功率。
所述充电需求功率用于指示为每个直流耦合单元中的储能单元分配的从N个直流耦合单元的能源单元获取的功率。
S530,总控制器根据所述N个直流耦合单元的放电需求功率和所述N个直流耦合单元的充电需求功率确定每个直流耦合单元的第一逆变功率值。
所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元向电网提供电能的功率,或所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元从电网吸收电能的功率。
在一种可能的实现方式中,结合以下步骤S511至S518对图13中步骤S510中获取放电需求功率的方式进行说明。
S511,总控制器获取N个直流耦合单元中每个直流耦合单元的第一功率值。
该第一功率值为每个直流耦合单元中能源单元的最大放电功率。
在一种可能的实现方式中,在每个直流耦合单元中的能源单元中包括至少一个光伏电池和至少一个光伏总控制器的情况下,总控制器可以从该至少一个光伏总控制器中获取该 至少一个光伏电池的最大放电功率。
其中,若光伏总控制器为MPPT控制器,MPPT控制器可以向总总控制器提供其对应的光伏电池的最大放电功率,其中,第j个直流耦合单元中的能源单元中的第i个光伏电池的最大放电功率为P
max_energy_ji。
需要说明的是,若MPPT控制器对应的光伏电池不处于MPPT点,该MPPT控制器向总总控制器提供的最大放电功率值可以是MPPT控制器对其对应的光伏电池放电功率的估计值,若MPPT控制器对应的光伏电池处于降额状态,该MPPT控制器向总控制器提供的最大放电功率值可以是降额之后的最大放电功率。
总控制器根据该至少一个光伏电池的最大放电功率获取N个直流耦合单元中每个直流耦合单元中能源单元的最大放电功率,其中,第j个直流耦合单元中能源单元的最大放电功率P
bus_max_energy_j为:
P
bus_max_energy_j=∑P
max_energy_ji (48)
也就是说,每个直流耦合单元中能源单元的最大放电功率为每个直流耦合单元中能源单元中的所有光伏总控制器所提供的光伏电池的最大放电功率之和。
S512,总控制器获取该N个直流耦合单元的总吸收功率值。
该吸收功率值是指为每个直流耦合单元中的能源单元分配的从电网吸收的功率值。
总控制器可以确定该N个直流耦合单元中每个直流耦合单元的吸收功率值,该总吸收功率值为该N个直流耦合单元的吸收功率值值之和,其中,确定N个直流耦合单元中每个直流耦合单元的吸收功率值可以与方法400描述的流程类似,为了简便,在此不再赘述。
也就是说总吸收功率值p
bat_from_grid为:
p
bat_from_grid=∑p
bus_bat_from_grid_j (49)
其中p
bus_bat_from_grid_j为该N个直流耦合单元中第j个直流耦合单元的吸收功率值。
S513,总控制器确定该N个直流耦合单元的总吸收功率值是否满足电网的需求。
在总吸收功率值等于电网所需的吸收需求功率的情况下,总控制器确定该N个直流耦合单元的总吸收功率值满足电网的需求。
也就是说,当该N个直流耦合单元的储能单元满足电网的需求时,并且该N个直流耦合单元的储能单元还可存储电能的情况下,若该N个直流耦合单元中还存在能源单元,总控制器可以将能源单元的功率分配给储能单元进行储存,从而提高了新能源电能的利用率。
在总控制器确定该N个直流耦合单元的总吸收功率值满足电网的情况下,总控制器可以根据总吸收功率值确定总充电需求功率。
该总充电需求功率是为N个直流耦合单元中的储能单元分配的从N个直流耦合单元中的能源单元获取的总功率。
在一种可能的方式中,S514,总控制器确定N个直流耦合单元的第一充电能力值。
该第一充电能力值为N个直流耦合单元中的能源单元可提供给储能单元电能的能力值。
总控制器可以根据下式确定N个直流耦合单元中能源单元给储能单元的第一充电能力值p
max_energy_to_bat_1为:
其中,p
bus_max_energy_j为N个直流耦合单元中第j个直流耦合单元的第一功率值。
S515,总控制器获取N个直流耦合单元中每个直流耦合单元中储能单元的最大充电功率。
在一种可能的实现方式中,在每个直流耦合单元中的储能单元包括至少一个储能电池和至少一个储能控制器的情况下,总控制器可以从该至少一个储能控制器中获取对应的储能电池的最大充电功率,还可以获取每个储能控制器的最大充电功率。
总控制器根据该至少一个储能电池的最大充电功率和该至少一个储能控制器的最大充电功率确定每个直流耦合单元中储能单元的最大充电功率,其中,该N个直流耦合单元中的第j个直流耦合单元中储能单元的最大充电功率P
bus_max_bat_charge_j为:
P
bus_max_bat_charge_j=∑min(p
bat_max_charge_ji,p
dcdc_max_charge_ji) (51)
其中,P
bat_max_charge_ji为第j个直流耦合单元中第i个储能电池的最大充电功率,P
dcdc_max_charge_ji为第j个直流耦合单元中第i个储能控制器的最大充电功率。
也就是说,储能电池与对应的储能控制器最终的最大充电功率为储能电池与对应的储能控制器的最大充电功率的最小值,直流耦合单元中的储能单元的最大充电功率为该直流耦合单元中全部储能电池与对应的储能控制器最终的最大充电功率之和。
需要说明的是,一个储能控制器可以控制一个或多个储能电池,本申请对此不作限定。
S516,总控制器确定N个直流耦合单元的第二充电能力值。
该第二充电能力值为N个直流耦合单元中的储能单元可接受的电能的能力值。
在一种可能的实现方式中,总控制器可以根据下式获取第二充电能力值p
bus_bat_rest_charge为:
也就是说,N个直流耦合单元的第二充电能力值为每个直流耦合单元中每个直流耦合单元中储能单元的最大充电功率与吸收功率值之差的和。
S517,总控制器获取总充电需求功率。
总充电需求功率是为N个直流耦合单元中的储能单元分配的从N个直流耦合单元中的能源单元获取的总功率;
在一种可能的实现方式中,总控制器可以根据以下公式确定总充电需求功率:
p
max_energy_to_bat=min(p
bus_bat_rest_charge,p
max_energy_to_bat_1) (53)
也就是说,总控制器可以确定第一充电能力值和第二充电能力值中的最小值作为总充电需求功率。
S518,总控制器获取N个直流耦合单元中每个直流耦合单元的放电需求功率。
在一种可能的方式中,总控制器可以根据下式确定N个直流耦合单元中每个直流耦合单元的放电需求功率,其中,第j个直流耦合单元的放电需求功率为:
也就是说,N个直流耦合单元中每个直流耦合单元的放电需求功率可以根据每个直流耦合单元的第一功率值,即直流耦合单元中能源单元的最大放电功率值占N个直流耦合单元的第一功率值之和的占比来分配总充电需求功率,从而获得为每个直流耦合单元中能源 单元分配的用于储存的功率。
在一种可能的实现方式中,结合以下步骤S5201至S5216对图13中步骤S520中获取充电需求功率的方式进行说明。
总控制器可以进行第三迭代计算,以确定N个直流耦合单元中每个直流耦合单元的充电需求功率。
S5201,总控制器获取N个直流耦合单元的第三限幅值。
该第三限幅值用于指示N个直流耦合单元中每个直流耦合单元中储能单元可提供的最大充电功率。
在一种可能的实现方式中,每个直流耦合单元的第三限幅值可以是每个储能单元可提供的最大充电功率。
可选地,当未给直流耦合单元的储能单元分配吸收电网的吸收功率值时,该储能单元可提供的最大充电功率为该直流耦合单元的最大充电功率。当给直流耦合单元的储能单元分配吸收电网的吸收功率值时,该储能单元可提供的最大充电功率为对应的最大充电功率与对应的吸收功率值的差值。
也就是说,能为储能单元分配的充电功率受到其本身的最大充电功率和已经分配的充电功率的限制。
S5202,总控制器获取N个直流耦合单元中每个直流耦合单元的第二能量值。
该第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差。
其中,总控制器可以从储能单元获取每个直流耦合单元中的储能单元的可提供的电能值总量,也可以在总控制器中预配置每个直流耦合单元中的储能单元的可提供的电能值总量。
总控制器获取N个直流耦合单元中每个直流耦合单元的第二能量值的方式可以与方法400中步骤S4301获取第二能量值的方式类似,为了简便,在此不再赘述。
S5203,总控制器计算N个直流耦合单元的初始候选充电需求功率。
在一种可能的实现方式中,总控制器根据以下公式,确定N个直流耦合单元中每个直流耦合单元的初始候选充电需求功率,其中,第j个直流耦合单元的初始候选充电需求功率为:
其中,p
bus_bat_charge_j表示N个直流耦合单元中第j个直流耦合单元的初始候选充电需求功率,SOE
bus_able_j表示N个直流耦合单元中第j个直流耦合单元的第二能量值,
为N个直流耦合单元的第二能量值之和,1≤j≤N。
S5204,总控制器在N个直流耦合单元中确定T个第六直流耦合单元。
在一种可能的实现方式中,第六直流耦合单元的初始候选充电需求功率大于或等于其对应的第三限幅值,T为正整数。
需要说明的是,第六直流耦合单元可以理解为在本次计算后处于第三限幅状态的直流耦合单元。
S5205,总控制器根据该T个第六直流耦合单元进行判定。
在T=0的情况下,S5206,总控制器确定该N个直流耦合单元的充电需求功率为其对应的初始候选充电需求功率,并结束第三迭代计算。
也就是说,在T=0的情况下,在本次计算后N个直流耦合单元都未处于第三限幅状态,总控制器可以确定该N个直流耦合单元的充电需求功率为其对应的初始候选充电需求功率。
在T=N的情况下,S5207,总控制器确定该T个第六直流耦合单元的充电需求功率为其对应的第三限幅值,并结束第三迭代计算。
也就是说,在T=N的情况下,在本次计算后N个直流耦合单元全部处于第三限幅状态,总控制器可以确定该N个直流耦合单元的充电需求功率为其对应的第三限幅值。
在0<T<N的情况下,S5208,总控制器确定该T个第六直流耦合单元的充电需求功率为其对应的第三限幅值。
总控制器先为该T个第六直流耦合单元分配充电需求功率,再执行S5209。
S5209,总控制器确定T
1个第五直流耦合单元。
该T
1个第五直流耦合单元为在之前的第三迭代计算中未被分配充电需求功率的直流耦合单元,T
1为正整数且T
1≤N。
需要说明的是,第五直流耦合单元也可以理解为在之前的第三迭代计算中计算获得的候选充电需求功率小于其对应的第三限幅值。
S5210,总控制器确定参考总充电需求功率。
在一种可能的实现方式中,根据以下公式,总控制器确定参考总充电需求功率:
其中,P
ref_3为参考总充电需求功率,
为已被分配充电需求功率的直流耦合单元的充电需求功率之和,p
bus_bat_charge_j为已被分配充电需求功率的直流耦合单元中第j个直流耦合单元的充电需求功率。
S5211,总控制器计算T
1个第五直流耦合单元的候选充电需求功率。
在一种可能的实现方式中,根据以下公式,总控制器确定该T
1个第五直流耦合单元的候选充电需求功率:
其中,p
bus_bat_charge_j表示所述T
1个第五直流耦合单元中第j个第五直流耦合单元的选充电需求功率,P
pref_3表示参考总充电需求功率,SOE
bus_able_j表示所述T
1个第五直流耦合单元中第j个第五直流耦合单元的第二能量值,
表示所述T
1个第五直流耦合单元的第二能量值之和,1≤j≤T
1。
S5212,总控制器在T
1个第五直流耦合单元中确定T
2个第六直流耦合单元。
其中,该T
2个第六直流耦合单元在S5211计算获得的候选充电需求功率大于或等于其对应的第三限幅值,T
2为正整数。
S5213,总控制器确定该T
2个第六直流耦合单元的充电需求功率。
该T
2个第六直流耦合单元处于第三限幅状态,也就是说,总控制器确定该T
2个第六直流耦合单元的充电需求功率为其对应的第三限幅值。
S5214,总控制器根据该T
1个第五直流耦合单元和该T
2个第六直流耦合单元进行判定。
在T
1=T
2的情况下,S5215,总控制器确定结束该多轮第三迭代计算。
此时,之前未被分配的T
1个第五直流耦合单元在S5213中全部被分配其对应的第三限幅值作为充电需求功率。
在T
1>T
2>0的情况下,回到S5209重新进行计算。
在T
2=0的情况下,S5216,总控制器确定该T
1个第五直流耦合单元的充电需求功率,并结束该多轮第三迭代计算。
该T
1个第五直流耦合单元的充电需求功率为对应的参考充电需求功率。
此时,在本轮计算中,该T
1个第五直流耦合单元都未处于第三限幅状态,总充电需求功率被分配完。
也就是说,经过第三迭代计算,总控制器可以确定N个直流耦合单元的充电需求功率。
在一种可能的实现方式中,结合以下步骤S5301至S5216对图13中步骤S530中获取第一逆变功率值的方式进行说明。
S5301,总控制器确定N个直流耦合单元中每个直流耦合单元的交换功率。
该交换功率为N个直流耦合单元中每个直流耦合单元的放电需求功率减去其对应的充电需求功率。
也就是说,N个直流耦合单元中第j个直流耦合单元的交换功率p
bus_pcs_to_other_j为:
p
bus_pcs_to_other_j=p
bus_energy_to_bat_j-p
bus_bat_charge_j (57)
S5302,总控制器根据N个直流耦合单元的第一候选逆变功率。
在一种可能的实现方式中,在存在直流耦合单元中的储能单元已被分配吸收电网的功率值,也就是第一吸收功率的情况下,N个直流耦合单元中每个直流耦合单元的第一候选逆变功率为每个直流耦合单元的交换功率与对应的吸收功率值之差,N个直流耦合单元中的第j个直流耦合单元的第一候选逆变功率值p
bus_pcs_to_grid_j_1为:
p
bus_pcs_to_grid_j_1=p
bus_pcs_to_other_j-p
bus_bat_from_grid_j (58)
也就是说,直流耦合单元中的逆变单元需要承受同一个直流耦合单元中的储能单元吸收的功率值,因此,逆变单元上实际承载的逆变功率,与同一个直流耦合单元中的储能单元吸收的功率值、能源单元给储能单元充电的功率,以及同一个直流耦合单元中的能源单元充电的功率相关。
S5303,总控制器获取N个直流耦合单元中每个直流耦合单元的第二功率值。
该第二功率值为每个直流耦合单元中逆变单元的最大放电功率。
在一种可能的实现方式中,在每个直流耦合单元中的逆变单元中包括至少一个逆变器的情况下,该总控制器获取每个逆变器的最大放电功率,其中,第j个直流耦合单元中的逆变单元中的第i个逆变器的最大放电功率为p
pcs_max_discharge_ji。
总控制器根据该至少一个逆变器的最大放电功率确定N个直流耦合单元中每个直流耦合单元中逆变单元的最大放电功率,其中,第j个直流耦合单元中逆变单元的最大放电功率,即第二功率值p
bus_max_pcs_discharge_j为:
p
bus_max_pcs_discharge_j=∑p
pcs_max_discharge_ji (59)
也就是说,每个直流耦合单元中逆变单元的最大放电功率为每个直流耦合单元中逆变单元中的所有逆变器的最大放电功率之和。
S5304,总控制器确定放电调整需求值。
该放电调整需求值为N个直流耦合单元中第一候选逆变功率值大于0,且第一候选逆变功率值大于对应的第二功率值的直流耦合单元的第一候选逆变功率值减去对应的第二功率值的差值之和。
也就是说,放电调整需求值Delta_pos_sum为:
需要说明的是,直流耦合单元的第一候选逆变功率值大于0,可以理解为该直流耦合单元的逆变单元处于放电状态,可以考虑该直流耦合单元的第一候选逆变功率值是否超过了逆变单元的最大放电功率值,如果超过了的话,则表明该直流耦合单元不可以承受第一候选逆变功率,该逆变单元被限幅,放电调整需求值就是N个直流耦合单元中逆变单元被限幅的直流耦合单元超过第二功率值的总和。
S5305,总控制器确定充电调整需求值。
该充电调整需求值为所述N个直流耦合单元中第一候选逆变功率值小于0,且第一候选逆变功率值小于对应的第四功率值的直流耦合单元的第四功率值减去对应的第一候选逆变功率值的差值之和。
该第四功率值为每个直流耦合单元中逆变单元的最大充电功率。
在一种可能的实现方式中,在每个直流耦合单元中的逆变单元中包括至少一个逆变器的情况下,该总控制器获取每个逆变器的最大充电功率,其中,第j个直流耦合单元中的逆变单元中的第i个逆变器的最大充电功率为p
pcs_max_charge_ji。
总控制器根据该至少一个逆变器的最大充电功率确定N个直流耦合单元中每个直流耦合单元中逆变单元的最大充电功率,其中,第j个直流耦合单元中逆变单元的最大充电功率,即第四功率值p
bus_max_pcs_charge_j为:p
bus_max_pcs_charge_j=∑p
pcs_max_charge_ji。
也就是说充电调整需求值Delta_neg_sum为:
其中,第一候选逆变功率值和第四功率值的负号代表功率方向为充电方向,充电方向可以理解为从电网经过逆变单元到储能单元的方向,其绝对值代表功率值的大小。
需要说明的是,直流耦合单元的第一候选逆变功率值小于0,可以理解为该直流耦合单元的逆变单元处于充电状态,可以考虑该直流耦合单元的第一候选逆变功率值的绝对值是否超过了逆变单元的最大充电功率值,如果超过了的话,则表明该直流耦合单元不可以承受第一候选逆变功率,该逆变单元被限幅,放电调整需求值就是N个直流耦合单元中逆变单元被限幅的直流耦合单元超过第四功率值的总和。
S5306,总控制器确定调整需求功率。
该调整需求功率为所述放电调整需求值减去所述充电调整需求值的差值的绝对值。
也就是说,调整需求功率Delta为:
Delta=|Delta_pos_max-Delta_neg_max| (62)
S5307,总控制器获取N个直流耦合单元中每个直流耦合单元的调整比例值。
该调整比例值为每个直流耦合单元的交换功率值占交换功率值大于0的直流耦合单元的交换功率值之和的占比。
也就是说,N个直流耦合单元中第j个直流耦合单元的调整比例值为:
其中,
S5308,总控制器确定N个直流耦合单元中每个直流耦合单元的第二候选逆变功率值。
其中,第一候选逆变功率值大于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第二功率值中的最小值,第一候选逆变功率值小于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第四功率值中的最大值。
也就是说:
若p
bus_pcs_to_grid_j_1>0
p
bus_pcs_to_grid_j_2=min(p
bus_pcs_to_grid_j_1,p
bus_max_pcs_discharge_j) (65)
若p
bus_pcs_to_grid_j_1<0
p
bus_pcs_to_grid_j_2=max(p
bus_pcs_to_grid_j_1,p
bus_max_pcs_charge_j) (66)
其中,p
bus_pcs_to_grid_j_2为N个直流耦合单元中第j个直流耦合单元的第二候选逆变功率值,p
bus_pcs_to_grid_j_1为N个直流耦合单元中第j个直流耦合单元的第一候选逆变功率值,p
bus_max_pcs_discharge_j为N个直流耦合单元中第j个直流耦合单元的第二功率值,p
bus_max_pcs_charge_j为N个直流耦合单元中第j个直流耦合单元的第四功率值。
S3309,总控制器在确定放电需求功率大于充电需求功率的情况下,确定交换功率值小于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值减去调整需求功率与对应的调整比例值乘积的差值,确定交换功率大于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值。
也就是说,
若Delta_pos_max>Delta_neg_max,
p
bus_pcs_to_other_j<0的直流耦合单元的第一逆变功率值为:
p
bus_pcs_to_grid_j=p
bus_pcs_to_grid_j_2-Delta*K
bus_j (67)
p
bus_pcs_to_other_j>0的直流耦合单元的第一逆变功率值为:
p
bus_pcs_to_grid_j=p
bus_pcs_to_grid_j_2 (68)
若Delta_pos_max<Delta_neg_max,
p
bus_pcs_to_other_j<0的直流耦合单元的第一逆变功率值为:
p
bus_pcs_to_grid_j=p
bus_pcs_to_grid_j_2 (69)
p
bus_pcs_to_other_j>0的直流耦合单元的第一逆变功率值为:
p
bus_pcs_to_grid_j=p
bus_pcs_to_grid_j_2-Delta*K
bus_j (70)
在一种可能的实现方式中,若直流耦合单元中的逆变单元包括多个逆变器,则可以根据每个逆变器的最大放电功率占第二功率值的占比分配第一逆变功率值,或根据每个逆变器的最大充电功率占第四功率值的占比分配第一逆变功率值。
例如,若p
bus_pcs_to_grid_j>0,
若p
bus_pcs_to_grid_j<0,
其中,p
pcs_to_grid_ji表示第j个直流耦合单元中的逆变单元中的第i个逆变器的逆变功率,p
pcs_max_discharge_ji表示第j个直流耦合单元中的逆变单元中的第i个逆变器的最大放电功率,p
pcs_max_charge_ji表示第j个直流耦合单元中的逆变单元中的第i个逆变器的最大充电功率。
从而,在本申请中,可以通过确定N个直流耦合单元中逆变单元的第一逆变功率值,实现将直流耦合单元的能源单元产生的电能给该直流耦合单元和/或其它直流耦合单元的储能单元充电,从而可以减少能源单元的电能浪费。
图14示出了本申请实施例提供的控制设备的结构示意图。该控制设备包括处理器1410、通信接口1420。可选地,该控制设备还可以包括存储器1430。可选地,存储器1430可以包括于处理器1410中。其中,处理器1410、通信接口1420和存储器1430通过内部连接通路互相通信,存储器1430用于存储指令,处理器1410用于执行存储器1430存储的指令,以实现本申请实施例提供的控制方法。
可选地,该控制设备可以用于执行图1中的总控制器101,或图2中光伏控制器2400至2600的功能,或图3中储能控制器3400至3600的功能。
可选地,该控制设备还可以用于执行图5或图13中任一项所展示的控制方法。
在本说明书中使用的术语“部件”、“模块”、“系统”等用于表示计算机相关的实体、硬件、固件、硬件和软件的组合、软件、或执行中的软件。例如,部件可以是但不限于,在处理器上运行的进程、处理器、对象、可执行文件、执行线程、程序和/或计算机。通过图示,在计算设备上运行的应用和计算设备都可以是部件。一个或多个部件可驻留在进程和/或执行线程中,部件可位于一个计算机上和/或分布在2个或更多个计算机之间。此外,这些部件可从在上面存储有各种数据结构的各种计算机可读介质执行。部件可例如根据具有一个或多个数据分组(例如来自与本地系统、分布式系统和/或网络间的另一部件交互的二个部件的数据,例如通过信号与其它系统交互的互联网)的信号通过本地和/或远程进程来通信。
本领域普通技术人员可以意识到,结合本文中所公开的实施例描述的各示例的单元及算法步骤,能够以电子硬件、或者计算机软件和电子硬件的结合来实现。这些功能究竟以硬件还是软件方式来执行,取决于技术方案的特定应用和设计约束条件。专业技术人员可以对每个特定的应用来使用不同方法来实现所描述的功能,但是这种实现不应认为超出本申请的范围。
所属领域的技术人员可以清楚地了解到,为描述的方便和简洁,上述描述的系统、装置和单元的具体工作过程,可以参考前述方法实施例中的对应过程,在此不再赘述。
在本申请所提供的几个实施例中,应该理解到,所揭露的系统、装置和方法,可以通过其它的方式实现。例如,以上所描述的装置实施例仅仅是示意性的,例如,所述单元的划分,仅仅为一种逻辑功能划分,实际实现时可以有另外的划分方式,例如多个单元或组件可以结合或者可以集成到另一个系统,或一些特征可以忽略,或不执行。另一点,所显示或讨论的相互之间的耦合或直接耦合或通信连接可以是通过一些接口,装置或单元的间接耦合或通信连接,可以是电性,机械或其它的形式。
所述作为分离部件说明的单元可以是或者也可以不是物理上分开的,作为单元显示的部件可以是或者也可以不是物理单元,即可以位于一个地方,或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部单元来实现本实施例方案的目的。
另外,在本申请各个实施例中的各功能单元可以集成在一个处理单元中,也可以是各个单元单独物理存在,也可以两个或两个以上单元集成在一个单元中。
所述功能如果以软件功能单元的形式实现并作为独立的产品销售或使用时,可以存储在一个计算机可读取存储介质中。基于这样的理解,本申请的技术方案本质上或者说对现有技术做出贡献的部分或者该技术方案的部分可以以软件产品的形式体现出来,该计算机软件产品存储在一个存储介质中,包括若干指令用以使得一台计算机设备(可以是个人计算机,服务器,或者网络设备等)执行本申请各个实施例所述方法的全部或部分步骤。而前述的存储介质包括:U盘、移动硬盘、只读存储器(read-only memory,ROM)、随机存取存储器(random access memory,RAM)、磁碟或者光盘等各种可以存储程序代码的介质。
以上所述,仅为本申请的具体实施方式,但本申请的保护范围并不局限于此,任何熟悉本技术领域的技术人员在本申请揭露的技术范围内,可轻易想到变化或替换,都应涵盖在本申请的保护范围之内。因此,本申请的保护范围应以所述权利要求的保护范围为准。
Claims (33)
- 一种电力系统,其特征在于,所述电力系统包括N个直流耦合单元,N个直流母线以及控制器,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直流耦合单元用于向电网供电,所述N个直流耦合单元中的每个直流耦合单元包括能源单元,所述能源单元用于产生电能,N为正整数;所述总控制器用于:获取所述电网的总入网需求功率,所述总入网需求功率是所述电网所需的入网功率;获取所述N个直流耦合单元的第一限幅值,所述第一限幅值用于指示每个直流耦合单元中的能源单元可向电网提供的最大放电功率;根据所述总入网需求功率和所述N个直流耦合单元的第一限幅值,确定所述N个直流耦合单元的第一入网功率值,所述第一入网功率值是指为每个直流耦合单元中的能源单元分配的输入电网的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元处于第一限幅状态,所述第一限幅状态是指为直流耦合单元分配的第一入网功率值等于其对应的所述第一限幅值。
- 如权利要求1所述的电力系统,其特征在于,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收所述能源单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能;所述总控制器具体用于:将以下项中的最小值确定为每个直流耦合单元的第一限幅值:每个直流耦合单元的第一功率值、每个直流耦合单元的第二功率值,其中,所述第一功率值为每个直流耦合单元中的能源单元的最大放电功率,所述第二功率值为每个直流耦合单元中逆变单元的最大放电功率。
- 如权利要求1或2所述的系统,其特征在于,所述总控制器具体用于:进行多轮第一迭代计算,以确定所述N个直流耦合单元的第一入网功率值,所述多轮第一迭代计算中的每轮第一迭代计算包括:确定L 1个第一直流耦合单元,所述第一直流耦合单元为在之前的第一迭代计算中未被分配第一入网功率值的直流耦合单元,所述L 1为正整数且L 1≤N;计算所述L 1个第一直流耦合单元的第一候选入网功率值,所述第一候选入网功率值是根据所述总入网需求功率以及所述L 1个直流耦合单元的第一功率值确定的,所述第一功率值为每个直流耦合单元中的能源单元的最大放电功率;根据所述L 1个第一直流耦合单元的第一候选入网功率值和第一限幅值,确定所述L 1个第一直流耦合单元的第一入网功率值。
- 如权利要求3所述的系统,其特征在于,所述总控制器具体用于:在所述L 1个第一直流耦合单元中确定L 2个第二直流耦合单元,所述第二直流耦合单元的第一候选入网功率值大于或等于其对应的第一限幅值,所述L 2为正整数;确定所述L 2个第二直流耦合单元的所述第一入网功率值,其中,所述L 2个第二直流 耦合单元处于第一限幅状态。
- 如权利要求4所述的系统,其特征在于,所述多轮第一迭代计算中的每轮第一迭代计算还包括:在L 1=L 2的情况下,确定结束所述多轮第一迭代计算;以及,在L 1>L 2的情况下,确定开始下一轮第一迭代计算。
- 如权利要求3所述的系统,其特征在于,所述总控制器具体用于:确定所述L 1个第一直流耦合单元的第一候选入网功率值均小于其对应的第一限幅值;确定所述L 1个第一直流耦合单元的第一入网功率值为其对应的第一候选入网功率值。
- 如权利要求3至6中任一项所述的系统,其特征在于,所述总控制器具体用于:满足以下条件,确定所述L 1个第一直流耦合单元的第一候选入网功率值:
- 一种电力系统的控制方法,其特征在于,所述方法应用于电力系统,所述电力系统包括N个直流耦合单元、N个直流母线以及总控制器,所述N个直流耦合单元用于向电网供电,其中,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直流耦合单元中的每个直流耦合单元包括储能单元,所述储能单元用于储存电能,N为正整数,所述方法包括:所述总控制器获取所述电网的储能入网需求功率,所述储能入网需求功率是指需要所述储能单元为所述电网提供的入网功率;所述总控制器获取所述N个直流耦合单元的第二限幅值,所述第二限幅值用于指示每个直流耦合单元中的储能单元可向电网提供的最大放电功率;所述总控制器根据所述储能入网需求功率和所述N个直流耦合单元的第二限幅值,确定每个直流耦合单元的第二入网功率值,所述第二入网功率值是指为每个直流耦合单元中的储能单元分配的输入电网的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元中的储能单元处于第二限幅状态,所述第二限幅状态是指为直流耦合单元分配的第二入网功率值等于其对应的所述第二限幅值。
- 如权利要求8所述的方法,其特征在于,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收所述储能单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能,所述总控制器获取所述N个直流耦合单元的第二限幅值,包括:所述总控制器将以下项中的最小值确定为每个直流耦合单元的第二限幅值:每个直流耦合单元的第二功率值,每个直流耦合单元的第三功率值,其中,所述第二功率值为每个直流耦合单元中逆变单元 的最大放电功率,所述第三功率值为每个直流耦合单元中的储能单元的最大放电功率。
- 如权利要求8所述的方法,其特征在于,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元和能源单元,所述能源单元用于产生电能,所述逆变单元用于通过所述直流母线接收所述能源单元和/或储能单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能,所述总控制器获取所述N个直流耦合单元的第二限幅值,包括:所述总控制器将以下项中的最小值确定为每个直流耦合单元的第二限幅值:每个直流耦合单元的第三功率值,每个直流耦合单元的剩余放电功率值,其中,所述第三功率值为每个直流耦合单元中的储能单元的最大放电功率,所述剩余放电功率值为每个直流耦合单元的第二功率值减去第一入网功率值,所述第二功率值为每个直流耦合单元中逆变单元的最大放电功率,所述第一入网功率值是指为每个直流耦合单元中的能源单元分配的输入电网的功率值。
- 如权利要求8至10中任一项所述的方法,其特征在于,所述总控制器根据所述储能入网需求功率和所述N个直流耦合单元的第二限幅值,确定所述N个直流耦合单元的第二入网功率值,包括:所述总控制器进行多轮第二迭代计算,以确定所述N个直流耦合单元的第二入网功率值,所述多轮第二迭代计算中的每轮第二迭代计算包括:所述总控制器确定M 1个第三直流耦合单元,所述第三直流耦合单元为在之前的第二迭代计算中未被分配第二入网功率值的直流耦合单元,所述M 1为正整数且M 1≤N;所述总控制器计算所述M 1个第三直流耦合单元的第二候选入网功率值,所述第二候选入网功率值是根据所述储能入网需求功率以及所述N个直流耦合单元的第一能量值确定的,所述第一能量值为每个直流耦合单元中的储能单元当前存储的电能;所述总控制器根据所述M 1个第三直流耦合单元的第二候选入网功率值和第二限幅值,确定所述M 1个第三直流耦合单元的第二入网功率值。
- 如权利要求11所述的方法,其特征在于,所述总控制器根据所述M 1个第三直流耦合单元的第二候选入网功率值和第二限幅值,确定所述M 1个第三直流耦合单元的第二入网功率值,包括:所述总控制器在所述M 1个第三直流耦合单元中确定M 2个第四直流耦合单元,所述第四直流耦合单元的第二候选入网功率值大于或等于其对应的第二限幅值,所述M 2为正整数;所述总控制器确定所述M 2个第四直流耦合单元的所述第二入网功率值,其中,所述M 2个直流耦合单元处于第二限幅状态。
- 如权利要求12所述的方法,其特征在于,所述多轮第二迭代计算中的每轮第二迭代计算还包括:所述总控制器在M 1=M 2的情况下,确定结束所述多轮第二迭代计算;以及,所述总控制器在M 1>M 2的情况下,确定开始下一轮第二迭代计算。
- 如权利要求11所述的方法,其特征在于,所述总控制器根据所述M 1个第三直流耦合单元的第二候选入网功率值和第二限幅值,确定所述M 1个第三直流耦合单元的第二入网功率值,包括:确定所述M 1个第三直流耦合单元的第二候选入网功率值均小于其对应的第二限幅值;确定所述M 1个第三直流耦合单元的第二入网功率值为其对应的第二候选入网功率值。
- 如权利要求11至14中任一项所述的方法,其特征在于,所述总控制器计算M 1个第三直流耦合单元的第二候选入网功率值,包括:满足以下条件,确定所述M 1个第三直流耦合单元的第二候选入网功率值:
- 一种电力系统,其特征在于,所述电力系统包括N个直流耦合单元、N个直流母线以及总控制器,所述N个直流耦合单元与所述N个直流母线一一对应,其中,所述N个直流耦合单元用于与电网传输电能,所述N个直流耦合单元中的每个直流耦合单元包括逆变单元,所述N个直流耦合单元中的每个直流耦合单元还包括能源单元和/或储能单元,所述逆变单元用于通过所述直流母线,接收所述能源单元输出的电能,以及在对电能进行直流转交流变换之后,向电网提供电能,所述逆变单元还用于通过所述直流母线吸收所述电网的电能,以及对电能进行交流转直流变换后,向储能单元提供电能,所述能源单元用于产生电能,所述储能单元用于储存电能;所述总控制器用于:获取N个直流耦合单元的放电需求功率,所述放电需求功率用于指示为每个直流耦合单元中的能源单元分配的给N个直流耦合单元的储能单元充电的功率;获取N个直流耦合单元的充电需求功率,所述充电需求功率用于指示为每个直流耦合单元中的储能单元分配的从N个直流耦合单元的能源单元获取的功率;根据所述N个直流耦合单元的放电需求功率和所述N个直流耦合单元的充电需求功率确定每个直流耦合单元的第一逆变功率值,所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元向电网提供电能的功率,或所述第一逆变功率值用于指示每个直流耦合单元中的逆变单元从电网吸收电能的功率。
- 如权利要求16所述的系统,其特征在于,所述总控制器具体用于:获取总充电需求功率,所述总充电需求功率是为N个直流耦合单元中的储能单元分配的从N个直流耦合单元中的能源单元获取的总功率;获取所述N个直流耦合单元的第三限幅值,所述第三限幅值用于指示每个直流耦合单元中的储能单元可提供的最大充电功率;根据所述总充电需求功率和所述N个直流耦合单元的第三限幅值,确定每个直流耦合单元的充电需求功率,其中,所述N个直流耦合单元中的至少一个直流耦合单元中处于第三限幅状态,所述第三限幅状态是指为直流耦合单元分配的充电需求功率等于其对应的所述第三限幅值。
- 如权利要求17所述的系统,其特征在于,所述总控制器具体用于:进行多轮第三迭代计算,以确定所述N个直流耦合单元的充电需求功率,所述多轮第三迭代计算中的每轮第三迭代计算包括:确定T 1个第五直流耦合单元,所述第五直流耦合单元为在之前的第三迭代计算中未被分配充电需求功率的直流耦合单元,所述T 1为正整数且T 1≤N;计算所述T 1个第五直流耦合单元的候选充电需求功率,所述候选充电需求功率是根据所述总充电需求功率以及所述N个直流耦合单元的第二能量值确定的,所述第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差;根据所述T 1个第五直流耦合单元的候选充电需求功率和第三限幅值,确定所述T 1个第五直流耦合单元的充电需求功率。
- 如权利要求18所述的系统,其特征在于,所述总控制器具体用于:在所述T 1个第五直流耦合单元中确定T 2个第六直流耦合单元,所述第六直流耦合单元的候选充电需求功率大于或等于其对应的第三限幅值,所述T 2为正整数;确定所述T 2个第六直流耦合单元的充电需求功率,其中,所述T 2个第六直流耦合单元处于第三限幅状态。
- 如权利要求19所述的系统,其特征在于,所述多轮第三迭代计算中的每轮第一迭代计算还包括:在T 1=T 2的情况下,确定结束所述多轮第三迭代计算;以及,在T 1>T 2的情况下,确定开始下一轮第三迭代计算。
- 如权利要求18所述的方法,其特征在于,所述总控制器具体用于:确定所述T 1个第五直流耦合单元的候选充电需求功率均小于其对应的第三限幅值;确定所述T 1个第五直流耦合单元的充电需求功率为其对应的候选充电需求功率。
- 如权利要求16至22中任一项所述的方法,其特征在于,所述总控制器具体用于:确定N个直流耦合单元的交换功率,所述交换功率为每个直流耦合单元的放电需求功率减去其对应的充电需求功率;根据所述N个直流耦合单元的交换功率确定调整需求功率;根据所述调整需求功率和所述N个直流耦合单元的交换功率确定N个直流耦合单元的第一逆变功率值。
- 如权利要求23所述的方法,其特征在于,所述总控制器具体用于:根据所述N个直流耦合单元的交换功率确定所述N个直流耦合单元的第一候选逆变功率值,所述第一候选逆变功率值为每个直流耦合单元的交换功率与对应的第一入网功率值之和,或者,所述第一候选逆变功率值为每个直流耦合单元的交换功率减去对应的吸收功率值的差值,其中,所述第一入网功率值为是指为每个直流耦合单元中的能源单元分配的输入电网的功率值,所述吸收功率值是指为每个直流耦合单元中的储能单元分配的吸收电网的功率值;根据所述N个直流耦合单元的第一候选逆变功率值和所述N个直流耦合单元的交换功率确定所述调整需求功率。
- 如权利要求24所述的方法,其特征在于,所述总控制器具体用于:确定放电调整需求值,所述放电调整需求值为所述N个直流耦合单元中第一候选逆变功率值大于0,且第一候选逆变功率值大于对应的第二功率值的直流耦合单元的第一候选逆变功率值减去对应的第二功率值的差值之和;确定充电调整需求值,所述充电调整需求值为所述N个直流耦合单元中第一候选逆变功率值小于0,且第一候选逆变功率值小于对应的第四功率值的直流耦合单元的第四功率值减去对应的第一候选逆变功率值的差值之和,其中,所述第二功率值为每个直流耦合单元中的逆变单元的最大放电功率,所述第四功率值为每个直流耦合单元中逆变单元的最大充电功率;确定所述调整需求功率,所述调整需求功率为所述放电调整需求值减去所述充电调整需求值的差值的绝对值。
- 如权利要求24或25所述的方法,其特征在于,所述总控制器具体用于:确定N个直流耦合单元的调整比例值,所述调整比例值为每个直流耦合单元的交换功率值占交换功率值大于0的直流耦合单元的交换功率值之和的占比;确定N个直流耦合单元的第二候选逆变功率值,其中,第一候选逆变功率值大于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第二功率值中的最小值,第一候选逆变功率值小于0的直流耦合单元的第二候选逆变功率值为对应的第一候选逆变功率值和对应的第四功率值中的最大值;在确定放电需求功率大于充电需求功率的情况下,确定交换功率值小于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值减去调整需求功率与对应的调整比例值乘积的差值,确定交换功率大于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值;以及在确定放电需求功率小于充电需求功率的情况下,确定交换功率值小于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值,确定交换功率值大于0的直流耦合单元的第一逆变功率值为对应的第二候选逆变功率值减去调整需求功率与对应的调整比例值乘积的差值。
- 一种功率控制方法,其特征在于,所述方法应用于电力系统,所述电力系统包括N个直流耦合单元、N个直流母线以及总控制器,所述N个直流耦合单元用于从电网吸收功率,其中,所述N个直流耦合单元与所述N个直流母线一一对应,所述N个直流耦合单元中的每个直流耦合单元包括储能单元,所述储能单元用于储存电能,N为正整数,所 述方法包括:所述总控制器获取所述电网的吸收需求功率,所述吸收需求功率为所述N个直流耦合单元中储能单元需要从电网吸收的功率;所述总控制器获取所述N个直流耦合单元的第四限幅值,所述第四限幅值用于指示每个直流耦合单元可提供的最大充电功率;所述总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,所述吸收功率值是指为每个直流耦合单元中的能源单元分配的从电网吸收的功率值,其中,所述N个直流耦合单元中的至少一个直流耦合单元处于第四限幅状态,所述第四限幅状态是指为直流耦合单元分配的吸收功率值等于其对应的第四限幅值。
- 如权利要求27所述的方法,其特征在于,所述N个直流耦合单元中的每个直流耦合单元还包括逆变单元,所述逆变单元用于通过所述直流母线接收电网的电能,以及对电能进行交流转直流变换之后,向所述储能单元传输电能,所述方法还包括:所述总控制器获取所述N个直流耦合单元的第四限幅值,包括:所述总控制器将以下项中的最小值确定为每个直流耦合单元的第四限幅值:每个直流耦合单元的第四功率值的绝对值,每个直流耦合单元的第五功率值,其中,所述第四功率值为每个直流耦合单元中逆变单元的最大充电功率,所述第五功率值为每个直流耦合单元中储能单元的最大充电功率。
- 如权利要求27或28所述的方法,其特征在于,所述总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,包括:所述总控制器进行多轮第四迭代计算,以确定所述N个直流耦合单元的吸收功率值,所述多轮第四迭代计算中的每轮第四迭代计算包括:所述总控制器确定Q 1个第七直流耦合单元,所述第七直流耦合单元为在之前的第四迭代计算中未被分配吸收功率值的直流耦合单元,所述Q 1为正整数,且Q 1≤N;所述总控制器计算所述Q 1个第七直流耦合单元的候选吸收功率值,所述候选吸收功率值是根据所述吸收需求功率以及所述Q 1个直流耦合单元的第二能量值确定的,所述第二能量值为每个直流耦合单元中的储能单元的可存储的电能值总量与已存储的电能值之差;所述总控制器根据所述Q 1个第七直流耦合单元的候选吸收功率值和第四限幅值,确定所述Q 1个第七直流耦合单元的吸收功率值。
- 如权利要求29所述的方法,其特征在于,所述总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,包括:所述总控制器在所述Q 1个第七直流耦合单元中确定Q 2个第八直流耦合单元,所述第八直流耦合单元的候选吸收功率值大于或等于其对应的第四限幅值,所述Q 2为正整数;所述总控制器确定所述Q 2个第八直流耦合单元的吸收功率值,其中,所述Q 2个第八直流耦合单元处于所述第四限幅状态。
- 如权利要求30所述的方法,其特征在于,所述多轮第四迭代计算中的每轮第四迭代计算还包括:所述总控制器在Q 1=Q 2的情况下,确定结束所述多轮第四迭代计算;以及,所述总控制器在Q 1>Q 2的情况下,确定开始下一轮第四迭代计算。
- 如权利要求29所述的方法,其特征在于,所述总控制器根据所述吸收需求功率和所述N个直流耦合单元的第四限幅值,确定N个直流耦合单元的吸收功率值,包括:确定所述Q 1个第七直流耦合单元的候选吸收功率值均小于其对应的第四限幅值;确定所述Q 1个第七直流耦合单元的吸收功率值为其对应的候选吸收功率值。
- 权利要求29至32中任一项所述的方法,其特征在于,所述总控制器计算Q 1个第七直流耦合单元的候选吸收功率值,包括:满足以下条件,确定Q 1个第七直流耦合单元的候选吸收功率值:
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| JP2019080485A (ja) * | 2017-10-25 | 2019-05-23 | 東芝Itコントロールシステム株式会社 | 電力変換器の運転制御装置および運転制御方法 |
| CN208955673U (zh) * | 2018-09-26 | 2019-06-07 | 深圳古瑞瓦特新能源股份有限公司 | 一种光储一体机装置 |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105811458A (zh) * | 2016-04-22 | 2016-07-27 | 深圳中电长城能源有限公司 | 微电网储能系统及其能量管理方法 |
| JP2019080485A (ja) * | 2017-10-25 | 2019-05-23 | 東芝Itコントロールシステム株式会社 | 電力変換器の運転制御装置および運転制御方法 |
| CN208955673U (zh) * | 2018-09-26 | 2019-06-07 | 深圳古瑞瓦特新能源股份有限公司 | 一种光储一体机装置 |
| CN113300398A (zh) * | 2021-04-30 | 2021-08-24 | 华为技术有限公司 | 电力系统和电力系统的控制方法 |
Non-Patent Citations (1)
| Title |
|---|
| See also references of EP4322360A4 |
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