CN203883473U - Double-frequency ship shore power device - Google Patents

Abstract

The utility model discloses a double-frequency ship shore power device. The device comprises a phase-shifting transformer, a power frequency conversion unit, a filter unit, a frequency meter and an electric quantity metering device. The secondary side of the phase-shifting transformer is connected to the electric quantity metering device successively through the power frequency conversion unit, the filter unit and the frequency meter. The electric quantity metering device comprises a current transformer, a voltage transformer and a electric energy meter. The current transformer and the voltage transformer are connected to the electric energy meter. The double-frequency ship shore power device utilizes the frequency meter to automatically detect two different frequencies, 50Hz and 60Hz, is high incompatibility, utilizes a special voltage transformer and a special current transformer to collect related data, and then accurately determines 50Hz/60Hz electric amount.

Description

A dual-frequency ship shore power device

technical field

The utility model relates to ship shore power technology in the field of electric power technology, in particular to a dual-frequency ship shore power device.

Background technique

In 2011, the Ministry of Transport issued the "Twelfth Five-Year Plan" Water Transport Energy Conservation and Emission Reduction Overall Promotion Implementation Plan. The overall goal is that by 2015, the awareness of energy conservation and emission reduction in the water transport industry will be further enhanced, energy utilization efficiency will be significantly improved, and the intensity of carbon dioxide emissions will be significantly reduced. , the management and operation mechanism is basically established, the policy and regulation system, the standard specification system, the technical support system and the statistical monitoring and assessment system are basically formed; the energy consumption structure of the water transportation industry is effectively improved, and the large-scale, professional and modern level of transport ships and port equipment is remarkable Energy conservation and emission reduction technologies have been widely promoted and applied; the energy conservation and emission reduction capabilities of the water transportation industry have been significantly enhanced, and the water transportation energy conservation and emission reduction goals set in the "Twelfth Five-Year Plan for Energy Conservation and Emission Reduction in Highway and Waterway Transportation" have been fully completed.

Its main indicators are that by 2015, compared with 2005, the comprehensive energy consumption of the port production unit throughput will drop by more than 8%; 14% or more. The carbon dioxide emissions of port production unit throughput will drop by more than 10%; the carbon dioxide emissions of operating ship unit transportation turnover will drop by more than 16%, of which ocean ships and inland ships will drop by more than 17% and 15% respectively.

Since the power grid frequency of my country's port and wharf power supply system is 50Hz, and many large ships at home and abroad use 60Hz ship electrical appliances, if the land grid is used for power supply, the difference in the power supply system between the port and the ship will inevitably have a serious impact on the ship's electrical equipment. Since the 50Hz alternating current cannot be directly used, frequency modulation is required to adjust the grid frequency to 60hz before supplying power to the ship.

In this regard, many domestic manufacturers have carried out research and pilot projects on shore power project technology, and have applied for related patents, including 50Hz and 60Hz dual-frequency power supply, high-voltage frequency conversion, etc. However, there is no mature technical solution for power metering and electricity fee calculation, only simple 50Hz metering and billing or 60Hz metering and billing, which cannot adapt to the uncertainty of domestic ship shore power tariff policies, and the compatibility is not high.

Utility model content

The purpose of the utility model is to disclose a dual-frequency ship shore power device to overcome the defects of immature power measurement technology and low compatibility of the traditional ship shore power device.

A dual-frequency ship shore power device provided by the embodiment of the utility model includes: a phase-shifting transformer, a power frequency conversion unit, a filter device, a frequency meter and a power metering device; the secondary side of the phase-shifting transformer passes through the power frequency conversion unit, the filter The device and the frequency meter are connected with the electricity metering device; the electricity metering device includes a current transformer, a voltage transformer and an electric energy meter, and the current transformer and the voltage transformer are respectively connected with the electric energy meter.

In the above technical solution, the electricity metering device includes at least two groups of current transformers and voltage transformers.

In the above technical solution, the dual-frequency ship shore power device also includes: an input switchgear and an output switchgear; the output end of the input switchgear is connected to the primary side of the phase-shifting transformer, and the input end of the output switchgear is connected to the power metering device .

In the above technical solution, the dual-frequency ship shore power device further includes a monitoring device; the monitoring device is connected to the input switch cabinet and the output switch cabinet respectively.

In the above technical solution, the monitoring device is respectively connected to the input switch cabinet and the output switch cabinet through the RS485 interface.

In the above technical solution, the monitoring device further includes a power meter.

In the above technical solution, the power frequency conversion unit includes a rectifier and an inverter; the inverter adopts an independent power supply.

In the above technical solution, the phase-shifting transformer is a multi-winding phase-shifting transformer.

A dual-frequency ship shore power device provided by the embodiment of the utility model is modularized and adaptive to different frequencies, and two different frequencies of 50Hz/60Hz are automatically detected by the frequency meter, and the compatibility is high; special voltage transformers and current transformers are used Collect relevant parameters, and then accurately determine the power; at the same time, real-time electricity bill settlement can be performed according to the power and the preset billing method, and each component can be configured to achieve modularization. The phase-shifting transformer can effectively reduce the harmonic pollution of the high-voltage inverter to the power grid, and will not cause harmonic interference to the power grid that exceeds the national standard, and realize step-down isolation; the control power supply of the inverter adopts a low-voltage independent of high-voltage The uninterrupted power supply technology enhances the optical fiber communication between the high-voltage main circuit of the system and the controller, and has strong anti-interference ability, safety and reliability.

Description of drawings

Fig. 1 is the first structural diagram of the dual-frequency ship shore power device in the embodiment of the utility model;

Fig. 2 is the circuit diagram of the power frequency conversion unit in the utility model embodiment;

Fig. 3 is a structural diagram of the electricity metering device in the embodiment of the utility model;

Fig. 4 is a second structural diagram of the dual-frequency ship shore power device in the embodiment of the utility model.

Detailed ways

A specific embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific embodiment.

A dual-frequency ship shore power device provided by the embodiment of the present invention, as shown in Figure 1, includes: a phase-shifting transformer 10, a power frequency conversion unit 20, a filtering device 30, a frequency meter 40 and a power metering device 50; a phase-shifting transformer The secondary side of 10 is connected to the power metering device 50 through the power frequency conversion unit 20 , the filtering device 30 , and the frequency meter 40 in sequence. Wherein, the electricity metering device 50 includes a current transformer, a voltage transformer and an electric energy meter, and the current transformer and the voltage transformer are respectively connected to the electric energy meter. In the embodiment of the utility model, the phase-shifting transformer 10, the power frequency conversion unit 20 and the filtering device 30 are combined into a high-voltage frequency converter.

In the embodiment of the utility model, the phase-shifting transformer 10 adopts a multi-winding phase-shifting transformer. The primary side of the phase-shifting transformer 10 is directly connected to the high-voltage grid, and the secondary side has multiple three-phase windings. Through the phase-shifting transformer, harmonics can be effectively eliminated (theoretically, harmonics below the 6n-1 order can be eliminated, n is the number of unit stages), so that the input current waveform is close to a sine wave, and the total harmonic distortion is lower than 3%. It will cause harmonic interference to the power grid that exceeds the national standard, effectively reduce the harmonic pollution of the high-voltage inverter to the power grid, and realize step-down isolation.

The power conversion unit 20 includes a rectifier and an inverter, and the inverter uses an independent power supply. The circuit schematic diagram of the power frequency conversion unit 20 is specifically shown in FIG. bridge inverter, wherein the diode rectifier bridge is composed of rectifier diodes T1-T6, and the H-bridge inverter is composed of insulated gate bipolar transistors (Insulated Gate Bipolar Transistor, IGBT) Q1-Q4. The power frequency conversion unit 20 is used to realize frequency conversion, and the output of high voltage (such as 6.6KV) is realized through the series connection of the power frequency conversion unit 20; the control power supply of the inverter adopts low-voltage uninterrupted power supply technology independent of high voltage, which enhances the The high-voltage main circuit communicates with the controller through optical fiber, which has strong anti-interference ability, safe and reliable.

The filter device 30 can use an active filter or a passive filter or a combination of the two to filter the output of the power frequency conversion unit to filter out or suppress harmonics of a set order.

The frequency meter 40 is an electronic measuring instrument specially used to measure the frequency of the signal to be measured, and generally consists of a time base (T) circuit, an input circuit, a counting display circuit and a control circuit. Its basic working principle is: when the number of cycles of the signal under test within a specific time period T is N, then the frequency of the signal under test is f=N/T. During a measurement cycle, the measured periodic signal is amplified, shaped and differentiated in the input circuit to form a narrow pulse of a specific period, which is sent to an input terminal of the main gate. The other input terminal of the main gate is the gate pulse generated by the time base circuit generating circuit. During the period when the gate pulse opens the main gate, the narrow pulse of a specific period can pass through the main gate to enter the counter for counting. The display circuit of the counter is used to display the frequency value of the measured signal, and the internal control circuit is used to complete various measurements. Switch between functions and implement measurement settings.

In the embodiment of the present utility model, as above, the electricity metering device 50 includes a current transformer, a voltage transformer and an electric energy meter, and the current transformer and the voltage transformer are respectively connected with the electric energy meter, and according to the frequency detected by the frequency meter 40 (50 Hz or 60Hz) to perform power metering adaptively. Specifically, the current transformer converts the high-voltage current into a low-voltage current and connects it to the current input terminal of the electric energy meter, and the voltage transformer converts the high voltage into a low voltage and connects it to the voltage input terminal of the electric energy meter. Electricity metering works. At the same time, the power metering device also completes the function of power transmission, and transmits the high-voltage voltage and current output by the filter device to the next-level equipment. Preferably, the electricity metering device 50 includes at least two sets of current transformers and voltage transformers, which are used to switch the sets of current transformers and voltage transformers under different frequency scenarios, and then measure the voltage and current respectively, see FIG. 3 for details As shown in Fig. 3, there are two sets of current transformers and voltage transformers as an example.

Preferably, as shown in FIG. 4, the dual-frequency ship shore power device also includes an input switch cabinet 60 and an output switch cabinet 70; the output end of the input switch cabinet 60 is connected to the primary side of the phase-shifting transformer 10, and the The input terminal is connected with the electricity metering device 50 . After connecting the cables at the standard inlet and outlet ports and locking them tightly, close the switch in the input switch cabinet 60, and then detect key indicators (including overvoltage, undervoltage, overfrequency, underfrequency, phase loss, phase reversal, power After the state of the frequency conversion unit, the state of the transformer, the ambient temperature, etc.) are correct, the operation of closing the switch in the output switch cabinet 70 can be performed according to the instructions of the external ship. At the same time, when the ship cannot stop power supply (for example, there is a patient emergency situation on the ship, there is a ship refrigerator, etc.), it is required that the power cannot be cut off at this time, and the ship's shore power device and the ship's generator are required to perform manual/automatic synchronous grid-connected operations.

Preferably, the dual-frequency ship shore power device further includes a monitoring device 80; the monitoring device 80 is connected to the input switch cabinet 60 and the output switch cabinet 70 respectively. Specifically, the monitoring device 80 is respectively connected to the input switch cabinet 60 and the output switch cabinet 70 through the RS485 interface. The monitoring device detects internal state indicators of the ship's shore power device through sensors, such as voltage, current, frequency, etc., and also includes three items of unbalance, overcurrent, temperature of key components, and alarms when abnormalities are detected.

Preferably, the monitoring device 80 also includes an electricity billing meter, which can accurately measure electricity for the dual-frequency ship shore power supply device and can perform various methods (peak-valley electricity price, ladder electricity price, two-part electricity price, contract electricity price, custom electricity price) etc.) billing. The electricity billing meter can adopt the existing equipment in the market, and can also use the AT89C51 single-chip microcomputer to design and complete the billing function. The ship shore power device provided by the embodiment of the utility model has a modularized 50Hz/60Hz self-adaptive power metering function through a power billing meter, and can satisfy billing in various ways.

A dual-frequency ship shore power device provided by the embodiment of the utility model is modularized and adaptive to different frequencies, and two different frequencies of 50Hz/60Hz are automatically detected by the frequency meter, and the compatibility is high; special voltage transformers and current transformers are used Collect relevant parameters, and then accurately determine the power; at the same time, real-time electricity bill settlement can be performed according to the power and the preset billing method, and each component can be configured to achieve modularization. The phase-shifting transformer can effectively reduce the harmonic pollution of the high-voltage inverter to the power grid, and will not cause harmonic interference to the power grid that exceeds the national standard, and realize step-down isolation; the control power supply of the inverter adopts a low-voltage independent of high-voltage The uninterrupted power supply technology enhances the high-voltage main circuit of the system and the optical fiber communication of the controller, which has strong anti-interference ability and is safe and reliable.

What is disclosed above is only a specific embodiment of the utility model, but the utility model is not limited thereto, and any changes conceivable by those skilled in the art should fall within the protection scope of the utility model.

Claims (8)

1. A dual-frequency ship shore power device, characterized in that it comprises: a phase-shifting transformer, a power frequency conversion unit, a filtering device, a frequency meter and a power metering device; The secondary side of the phase-shifting transformer is connected to the power metering device sequentially through the power frequency conversion unit, the filtering device, and the frequency meter; The electricity metering device includes a current transformer, a voltage transformer and an electric energy meter, and the current transformer and the voltage transformer are respectively connected to the electric energy meter. 2 . The dual-frequency ship shore power device according to claim 1 , wherein the electricity metering device includes at least two sets of current transformers and voltage transformers. 3. The dual-frequency ship shore power device according to claim 1, further comprising: an input switch cabinet and an output switch cabinet; The output end of the input switch cabinet is connected to the primary side of the phase-shifting transformer, and the input end of the output switch cabinet is connected to the electricity metering device. 4. The dual-frequency ship shore power device according to claim 3, further comprising a monitoring device; The monitoring device is respectively connected with the input switch cabinet and the output switch cabinet. 5 . The dual-frequency ship shore power device according to claim 4 , wherein the monitoring device is respectively connected to the input switch cabinet and the output switch cabinet through RS485 interfaces. 6 . The dual-frequency ship shore power device according to claim 4 , wherein the monitoring device further comprises a power billing meter. 7 . 7. The dual-frequency ship shore power device according to any one of claims 1-6, wherein the power frequency conversion unit includes a rectifier and an inverter; The inverter uses an independent power supply. 8. The dual-frequency ship shore power device according to any one of claims 1-6, wherein the phase-shifting transformer is a multi-winding phase-shifting transformer.