JPH082157B2 - Synchronous speed controller - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to frequency control of synchronous control when parallelizing a system of a turbine generator operating independently by a remote control and a sound operation line. Is.

[Technical background of the invention and its problems]

Most newly constructed hydroelectric power plants in recent years are unmanned power plants, and control and monitoring are performed from a distant control plant.

Also, in the event of a system accident or other outage, the entire system loses power and the recovery time is shortened.Therefore, the startup time is short and the trial transmission capacity is available. There are many requests to implement.

In particular, in the restoration of a large grid, multiple hydroelectric power stations individually carry out trial transmission of the grid in each area, and after the trial transmission is completed, synchronize with another healthy grid after appropriate trial transmission at an appropriate substation. Electric power is transmitted to the load in parallel after expanding the healthy system.

FIG. 5 is a configuration diagram when the conventional synchronization control is performed. 1 is an unmanned power plant, 2 is a water turbine, 3 is a generator, 4 is a main transformer, 5 is a parallel transformer or disconnector, 6 is a speed control device, 7 is a speed adjustment setting device, and 8 is a remote monitoring control device. 2 is a power station for transmitting electric power from the power station 1.

10 is a control station installed in a distant place to control and monitor the unmanned power plant 1, 11 is a master station of the remote monitoring control device, 12 is a signal for passing signals between the unmanned power plant 1 and the control station 10. It is a transmission line.

13 is a tethered system 9 of the unmanned power plant 1 and another system
Substation that can operate in parallel with 14, 14 is unattended power plant 1
And a transmission line capable of supplying power from another power plant, 15 is a breaker or disconnector for connecting the system 9 and the system 14, 16 is an instrument transformer for obtaining frequency information of the system 9 or system 14, Reference numeral 17 is an automatic synchronizer for inserting the parallel connector and the disconnector 15.

A conventional system restoration operation method will be described with reference to FIG. When a system accident occurs in the transmission line 9 connected to the unmanned power plant 1 and the system is completely stopped, the system recovery operation is performed after the accident recovery. First, the control station 10 gives an operation command to the generator 3 of the unmanned power plant 1 capable of trial transmission operation in the trial transmission mode via the master station 11 of the remote monitoring control device.

The operation command given from the control station 10 is received by the slave station 8 of the power plant 1 via the transmission line 12, and the start instruction is given to the water turbine 2. When the water turbine 2 rotates and approaches the rated rotation speed, excitation (not shown) is applied to the generator 3 to generate a voltage. Next, the parallel connection and the breaker 5 are turned on, and the power transmission line 9 and the generator are connected via the main transformer 4. Further, while confirming the safety of the system, the generated voltage of the generator 3 is gradually increased until the terminal voltage of the system 9 reaches the rated voltage.

At the stage where the safety of the grid is confirmed, a substation that is generally far away from the unmanned power plant 1 or the control plant 10 for supplying power to the load connected to the transmission line 9 before the grid accident 13
Utilizes the synchronizer 16 in order to connect the system parallel connector and the disconnector 15 which are connected to another sound system. At this time, frequency adjustment for matching the frequencies of both systems is performed on the water turbine 2 that was performing the trial power transmission of the unmanned power plant 1. At the control station 10, the operator obtains the frequency information of the sound system 14 by telephone,
Comparing with the frequency of the system 9 that was performing the accident recovery, when the system 9 is high, a down command is issued, and when it is low, an up command is issued.
Unattended power plant 1 transmission via. The command received by the slave station 8 through the transmission line 12 is given to the speed setter 7 to change the speed of the water turbine 2 by the speed control device 6. By changing the speed of the water turbine 2, the frequency of the system 9 is changed so that the automatic synchronizer 17 catches the synchronization point.

However, since this frequency adjustment command is manually executed by using the position of the selective control, it is necessary for the operator to judge the length of the operation time of the command depending on the magnitude of the frequency difference between the two systems. However, since the operating time of the frequency adjustment command received at the unmanned power plant 1 is cyclically transmitted via the transmission line 12, the data update of the cyclic transmission and the transmission time are added to the time commanded by the operator. An error will occur in the adjustment command. Further, since the speed setter 7 for changing the speed of the water turbine 2 is driven in proportion to the frequency adjustment command received at the unmanned power plant 1, the frequency adjustment of the system 9 is finally performed accurately. I can't do it. Therefore, the frequency control for matching the frequencies of both systems requires a very long time, and the control technique required by the operator also requires a great deal of skill.

In addition, even though the unmanned power plant 1 was used to shorten the time for system restoration and a trial power transmission was performed from a distance, the power was supplied for a long time at the time of receiving the load. Therefore, the total time until the final stage is completed becomes long.

[Object of the Invention]

Therefore, an object of the present invention is to more reliably adjust the frequency of a turbine generator operating independently when performing system parallel with other healthy systems after confirming system safety by trial transmission. It is an object of the present invention to obtain a uniform speed control method capable of completing parallelization of a system in a short time by simply performing it and shortening a system recovery time.

[Outline of Invention]

The present invention, when the system parallel with the healthy system after trial transmission at the time of system fault recovery is carried out at a distant substation or the like, conventionally, the frequency adjustment from a distant control station is proportional to the command operation time, that is, the command pulse width. In order to improve the above-mentioned inconvenience caused by adopting the method of controlling the rotation speed of the water turbine generator, the present invention responds to the increase and decrease pulse number of the frequency adjustment command from the remote control station. Then, the rotational speed of the water turbine generator is controlled based on the control signals of the preset constant variation and constant acceleration.

Example of Invention

An embodiment of the present invention will be described below with reference to FIG. 1, FIG. 2, FIG.
This will be described with reference to FIG. FIG. 1 is a block diagram of a hydroelectric power plant when carrying out the synchronous control of the present invention. Here, 18 is a speed control auxiliary device that outputs an acceleration signal in an amount proportional to the pulse of the frequency adjustment command from the slave station 8 of the distant monitoring control device to the speed control device 6 to perform synchronous uniform speed. The speed control auxiliary device 18 is used only for frequency adjustment during the trial transmission operation, and is electrically excluded from the speed control device 6 during normal operation.

FIG. 2 shows a circuit configuration of the speed control auxiliary device 18. 25A
(25B) is a portion for receiving a signal for raising (lowering) the frequency adjustment command from the slave station 8 of the remote monitoring control device, 22A (22B)
Is a measuring circuit for counting the number of pulses of arbitrary width received from the 25A (25B), 23A (23B) is a memory circuit for storing the value counted by the counting circuit 22A (22B), and 24A (24B) is the counting circuit. 22A (22B) and the memory circuit 23A (23B) are controlled to sequentially generate the raising (lowering) rate command for the number of times stored, and the 26A (26B) outputs the rate command from the 24A (24B). This is a part to be given to the speed control device 6.

FIG. 3 is a time chart showing the function of the speed control assisting device 18. Where UCP (DCP) is
25A (25B) frequency adjustment control rise command (decrease command) pulse, f ₀ is the reference frequency of the generator 3, A is the rise command (decrease command) pulse UCP (DCP) per time The frequency change amount to be adjusted, t _1, is controlled per rise command (decrease command) pulse UCP (DCP) determined by the increase (decrease) rate command generation circuit 24A (24B) in FIG. Is the period for implementing.

FIG. 4 is a time chart of the synchronous speed control of the present invention. 19 is the frequency of the grid 9 charged by the turbine generator 3,
20 indicates the frequency of the sound system 14, and 21 indicates the synchronization point between the system 9 and the system 14.

In Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 4, while confirming the normality of the system by the generator 3 of the unmanned power plant 1 in order to restore the system of the system 9 which was completely stopped due to the system accident. Then, the terminal voltage of the generator 3 is gradually increased, the voltage is increased to the rated voltage at the end of the system 9, and the trial transmission is completed. After that, the healthy system 14 and the system 9 confirmed to be normal by the trial transmission are connected in parallel.

First, the control station 10 obtains the frequency information of the sound system 14, compares and determines the current frequency value of the system 9 that has finished the trial transmission, and controls the increase or decrease of the frequency control command via the transmission line 12. Are performed an appropriate number of times. In the present invention, a case where the frequency of the grid 9 is low after the trial power transmission will be described below as an example.

Pulse UCP for frequency adjustment command from controller 10
Is input to the raising command input unit 25A of the speed control auxiliary device 18 n times at an arbitrary interval via the slave station 8 of the distant monitoring control device.

The number of pulses of an arbitrary interval and width received by the raising command input unit 25A of the speed control auxiliary device 18 is stored in the storage circuit 23A at the same time as the counting circuit 22A counts the number of pulses. A circuit that generates the frequency increase rate (A / t ₁ ) command at the same time
Outputs the start of command output to 24A. The circuit 24A for generating the frequency increase rate command outputs the end to the counting circuit 22A when one control is completed. Here, the counting circuit 24A subtracts 1 from the n number of times stored in the storage circuit 23A, and when the remaining number is not 0, the above control is sequentially repeated. Of course, if a pulse command is input from the slave station 8 of the remote monitoring control device during the rate control, it is counted by the clock circuit 22A and stored in the memory circuit 23A.

An acceleration rate (A / t ₁ ) command for increasing frequency is output from the 26A to the speed governor control device 6, whereby the turbine generator 3 is accelerated, and the frequency of the grid 9 is a constant rate (A / t ₁ ). Will continue to rise.

As a result, the frequency 19 of the generator 3 and the frequency of the sound system 20
Pass sync point 21 with 20. At this time, the substation 13 finds the synchronization point 21 of the sound line 14 taken in via the instrument transformer 16 and the system 9 in which the accident has been recovered by the automatic synchronizer 17 so that the system is paralleled and the disconnector 15 is given an automatic closing command. When the charging is completed, the information about the system paralleling and the breaker 15 is obtained at the control station 10, and the charging information is stored. The stored information is given to the master station 11 as a selection command. Information of the system parallel connection and the disconnector 15 introduced into the slave station 8 through the transmission line 12 is given from the slave station 8 to the speed control auxiliary device 18. The speed control auxiliary device 18 excludes the uniform speed control that has been performed so far by confirming that the system 15 is connected in parallel and the disconnector 15 is turned on.

Further, when the frequency of the system 9 after the trial power transmission is high, the same control as described above is performed using the circuit on the lower side.

〔The invention's effect〕

When the system parallel operation is performed as described above, the frequency control for the unmanned power plant can be performed only by giving an arbitrary frequency adjustment command any number of times, which is left to the operator's judgment.

That is, the speed control device of the present invention controls the conventional control that changes the magnitude of the command according to the operating time and takes a long time in the system parallel due to the delay of the transmission time due to the transmission path. By increasing or decreasing the frequency control amount per command at a constant rate, the system parallelization can be completed accurately in a short time. This also simplifies the operations performed by the operator and reduces the burden on the operator.

Even when the trial power transmission is performed by a plurality of units, the synchronous uniform velocity control device of the present invention can handle it.

[Brief description of drawings]

FIG. 1 is a block diagram of a hydroelectric power plant for explaining an embodiment of the present invention, FIG. 2 is a circuit block diagram of a speed control auxiliary device 18,
FIG. 3 is a time chart showing the operation of the speed control auxiliary device, FIG. 4 is a time chart showing the characteristics thereof, and FIG. 5 is a configuration diagram of a hydraulic power plant for explaining a conventional example. 1 ... Power plant, 2 ... Turbine 3 ... Turbine generator, 4 ... Main transformer 5 ... Parallel breaker and breaker, 6 ... Speed control device 7 ... Speed adjustment setter, 8 ... … Remote monitoring and control equipment 9 …… Transmission line, 10 …… Control station 12 …… Transmission line, 13 …… Substation 14 …… System, 15 …… Shear breaker 16 …… Measurement transformer, 17 …… Automatic synchronizer 18 ... Speed control auxiliary device

Claims (1)

[Claims] 1. A synchronous uniform speed controller for synchronously paralleling a system having a generator operated by a distant control station to a healthy system, provided that the system voltage reaches a rated voltage. If the system frequency of the generator is smaller than the frequency of the sound system, the first counting means for counting the increased pulses output from the remote control station, and the condition that the system voltage of the generator has become the rated voltage A second counting means for counting the deceleration pulse output from the remote control station when the system frequency of the generator is higher than the healthy system frequency, and the count values in the first and second counting means. Accordingly, the synchronous uniform speed control device is provided with a control signal output means for outputting a signal for controlling the generator at a preset constant variation and constant acceleration.