JPS61270780A - Power system simulation system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power system simulation method applied to a training device for maintaining and improving system operation techniques and skills of control station personnel.

[Conventional technology 0] Figure 4 is a processing conceptual diagram of a conventional power system simulation method). In the figure, 1 is a CRT device, 2 is an accident sequence data file, and 3 is an SV status change data file. In the simulation method, as will be described later, during the training preparation stage, the transient stability calculation step is executed, and during the training execution stage, the frequency and power flow calculation step is performed.
Execute.

Next, the operation will be explained.

First, in the training preparation stage, the trainer
In addition to the time of failure occurrence, failure point, and failure type in the electric power system, the operating relays such as main protection relays or back-up protection relays that are considered to operate due to these system failures, and the circuit breakers (CBs) that lip operate due to the operation relays. ) using a light pen.

The set data is stored in the accident sequence data file 2, and is also stored in the accident sequence data file 2.
Data regarding B) is also saved in the SV condition change data file 4.

Next, remove 111i11. However, since it is difficult for the trainer to correctly set this, I decided to run the transient stability calculation program using the accident sequence data file 2 as input data.
), as a result of the determination, the operating SO relay and trip C
The state of B is stored in the SV state change data file.

When the transient stability calculation reaches the termination time, the contents of the SV state change data file are rearranged in chronological order according to the trainer's instructions. This completes the training preparation stage.

Next, in the training execution stage, the power flow calculation and frequency calculation programs are executed while extracting the state changes of the circuit breaker (CB) from the SV state change data file 3 in chronological order. Alternatively, a real-time simulation of the power system can be performed by simulating the operation of a voltage/reactive power control device. The details of this real-time simulation will be explained below according to the flowchart of FIG. As for the overall operation of this real-time simulation, frequency calculation and power flow calculation are performed in conjunction every T seconds, and frequency calculation is performed continuously n (=T/ΔT) times at every 21 seconds.

Tsumashi, frequency calculation tΔT seconds increments n (=T/ΔT)
A real-time simulation is realized by repeating the calculation several times and performing one load flow calculation at that time, and performing all processing in T seconds of real time. Note that, normally, power flow calculation and frequency calculation are divided and processed by separate computers to realize a real-time simulation tube.

The detailed operation is as follows: First, extract the SV status change data from the SV status change data file 3 at the relevant time, determine whether there is a change in the switch 1 status (Step 2), and if there is a change, perform system separation calculation. Then, the separated system is determined, the admittance matrix of the system is corrected, and the system capacity and total inertial capacity i1 of the separated system are calculated (step 2). Subsequently, after completing this system separation calculation, power flow calculation is executed (step ■).

On the other hand, if it is determined that there is no change in step ■,
Check whether there is a discontinuous change in the active power of the bus due to loading or disconnection, etc. (Step ■). If there is no change, execute system frequency calculation for each separated system in the same way as completing the power flow calculation (Step ■). Then, the operation of the relay that responds to the system frequency is simulated (step ■), and these processes t
- Repeat 9 times (T/JT). Note that if it is determined in step (2) that there is a discontinuous change, the process in step (2) is executed.

Next, if all of the above processes are repeated, calculate the power flow at that point f: Execute Step ■), and then simulate the operation of the overload relay or voltage/reactive power control device that responds to the grid voltage, power flow of the power transmission line, etc. Finally, real-time synchronization processing (dela)')t' execution to synchronize T seconds for one cycle (step @),
The simulation for T seconds is completed. Next, the simulation for the next cycle begins.

T seconds is usually about 3 to 5 seconds, and ΔT is about 0.25 seconds.

T seconds is determined from the information update cycle of the actual power supply automation system), and a simulation that satisfies this performance is defined as a real-time simulation.

[Problem that the invention seeks to solve]

Conventional power system simulations are as described above, so it is necessary to simulate the operation of the main protection and backup protection relays in the form of trainer settings. If the breaker of the equipment is turned on, the system may fail again, and there are problems in that the operation of the main protection and backup protection relays cannot be simulated.

This invention was made to eliminate the above-mentioned problems by 1 km, and automatically processes the operation simulation of the main protection and backup protection relays when a system failure occurs, and automatically determines the power failure state. Another object of the present invention is to obtain a power system simulation method that can simulate the behavior of a power system in the same way as an actual power system even if a system failure occurs again due to a trainer's erroneous operation. , [Means for Solving the Problems] The power system simulation method according to the present invention simulates the operation of the main protection and backup protection relays based on stability calculations, and uses the calculation results in frequency and power flow calculations. Real-time simulation was realized by reflecting the above.

[Effect]

The power system simulation method in this invention is as follows:
Based on the stability calculation, the operation simulation of the main protection and backup protection relays is automatically processed, eliminating the need for manual settings during the training preparation stage of the trainer. To enable training in the case of a failure to be performed in the same way as in an actual system.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

w, In Figure 1, 1 is a CRT device, 2 is an accident sequence data file, and 3 is an SV state change data file.Even in the simulation method of this invention, the step of transient stability calculation and the step of power flow/frequency calculation are ■Execute and.

FIG. 2 is an explanatory diagram showing the presence or absence of a system failure, the operation status of transient stability calculation, and power flow/frequency calculation.

Next, the operation of the above embodiment will be specifically explained according to the flowcharts in FIGS. 3(a) and 3(b).

First, in the training preparation stage, the trainer uses the CRT device 1.
On the screen, set the time of failure occurrence, failure point, and failure type in the power system using a light pen. The set data is stored in the accident sequence data file 2. Next, the operation of the main protection and back-up protection relays, including the step-out relay, is judged by running a transient stability calculation program using the accident sequence data file 2 as input data, and the judgment results are shown below. SV for each status of main protection/backup protection operating relays and circuit breaker (cB) including IJ relays
It is stored in the state change data file 3 (step ■).

This transient stability calculation needs to be performed until the operation determination of the step-out relay is completed, but it is performed in T seconds (usually 3 to 5 seconds), which is one cycle of power flow/frequency calculation. Note that since the operation determination of the step-out relay normally takes 1 to 2 seconds, the above-mentioned cut-off time is sufficient.

Next, in the training execution stage, as shown in Figure 1, the main protection
Transient stability calculations, including simulating the operation of backup protection relays, and power flow/frequency calculations, which are power system simulations, are executed in parallel (Step ■).

0). In addition, as shown in Figure 2, from the start of the training execution stage to T seconds, the operation of the main protection and backup protection relays is determined by the transient stability calculation (step ■) in the training preparation stage. Transient stability calculation is not executed, but power flow calculation and frequency calculation t-are executed (step ■).

In the subsequent simulation step, the transient stability calculation and power flow/frequency calculation are processed in parallel.

However, transient stability calculations are not performed if no failure occurs within the relevant cycle.

In addition, although transient stability calculations are processed according to the flowcharts shown in Figures 3(a) and (b), data on the failure occurrence time, failure point, and failure type are extracted from the accident sequence file 2, and If a failure occurs between T seconds after T seconds, perform transient stability calculation ft, simulate the operation of the main protection and back-up protection relays, and check the operating relay and circuit breaker (CB).
The data is stored in the SV state change data file 3 with the time added. Rather than the trainer simulating the operation of the main protection/backup protection relay as in the past, the operation is simulated by transient stability calculation and is stored in the SV data file 3.

Next, to explain the process flow, first step O) determines whether or not a failure has occurred in the relevant cycle.
If no failure occurs, the calculation ends. On the other hand, if a failure has occurred, the power flow calculation results from one cycle before the current cycle are taken in (step O). Then, calculate the initial values of the generator's internal voltage and phase angle (Step O), and further calculate the load admittance from the load's bus voltage, active power, and reactive power to treat the load as a constant impedance load (Step 0). ).

Next, the admittance matrix of the positive phase, negative phase, or zero phase circuit is calculated depending on the fault type (step @).

Next, it is determined whether or not there is a change in the connection state of one system (step [phase]), and if there is no change, the process branches to circuit network calculation processing. On the other hand, if there is a change, it is then determined in step O) whether a failure has occurred, and if no failure has occurred, the process moves to a process of determining whether or not to remove the failure. On the other hand, if there is a fault, the fault equivalent impedance to be added to the positive-phase circuit is calculated based on the admittance matrices of the negative-phase and zero-phase circuits according to the type of fault (step [phase]).

Next, it is determined whether or not one fault has been removed (step O). If not, the process moves to changing the admittance matrix, and if it is, the fault impedance is treated as infinite in line 5 (step [phase]). Next, the admittance matrix of the positive phase circuit is changed accordingly (Step O), and the voltage and current of one circuit network are calculated (Step [Phase]).
.

Next, the electrical output of the generator is determined using the voltage obtained in step [share] and the 'fjL current (step 0), and further, by 1 above, the voltage of the network, the current and the internal phase angle of the generator are determined. Now that it has been determined, the operations of various main protection and back-up protection relays, including the step-out relay, are simulated (step [phase]). Subsequently, based on the operation simulation in step [phase], it is determined whether or not there is a relay operation (step [phase]), and if there is no relay operation, the process moves to a process of determining the calculation end time. On the other hand, if there is a relay operation, depending on the relay operation, 9) select the circuit breaker (CB) that will rip and save the data in the aV state change data file 3 (step ■), then calculate It is determined whether or not the time has reached T seconds (step [phase]); if it has, the calculation is terminated; if not, it is updated by the time Δt, and the processes from step [phase] are repeated.

On the other hand, as shown in Figure 1, power system simulation is performed using circuit breaker (CB) data from aV state change data file 3.
Performs real-time simulation of the power system by extracting state change data in chronological order, executing power flow calculation and frequency calculation programs, and simulating the operation of overload relays, frequency drop relays, or voltage/reactive power control devices. . The details of this real-time simulation will be explained below according to the flowchart of FIG.

As for the overall operation, frequency calculation and power flow calculation are performed in conjunction every T seconds, and frequency calculation is performed every 21 seconds.
Continuously calculate (= T/ΔT) times.

Then, calculate the frequency in 21 second increments (=T/ΔT).
A real-time simulation is realized by repeating the calculation several times and performing one load flow calculation at that time, and performing all processing in T seconds of real time. Note that, normally, power flow calculation and frequency calculation are divided and processed by separate computers to perform real-time simulation.

The detailed operation is as follows: First, extract the SV status change data from the SV status change data file 3 at the relevant time and determine whether there is a change in the switch status (Step 2). If there is a change, perform system separation calculation. Determine the presence or absence of a re-failure due to incorrect operation of the trainer, and if so, save the data in the SV state change data file 3, determine the separated system, correct the admittance matrix of the system, and calculate the system capacity and total inertia of the separated system. Calculate capacity, etc. (step ■). Subsequently, after completing this system separation calculation, power flow calculation is executed (step ■). On the other hand, if it is determined in step ■ that there is no change, check whether there is a discontinuous change in the active power of the bus due to load cutting etc. (step ■), and if there is no change, proceed as in the same way as ending the power flow calculation. The system frequency calculation for each separated system is executed (Step 2), followed by simulating the operation of the relay that responds to the system frequency (Step 2), and these processes are repeated n times (T/ΔT). Note that if it is determined in step (2) that there is a discontinuous change, the process in step (2) is executed.

When the above process is repeated n times, the power flow calculation at that point is executed (Step ①), and the operation simulation of an overload relay or voltage/reactive power control device that responds to the grid voltage, power flow, etc. 1! - Execute step [phase]), and finally execute real-time synchronization processing (delay) for synchronization of 1 cycle and 1 second (step 2), completing the 7-second simulation. Next, the simulation for the next cycle begins. Note that the system operation data by the trainer is input into the SV state change data file 3 in a program separate from the simulation. Further, T seconds is usually 3 to 5 seconds, and ΔT is about 0.25 seconds.

In the power system simulation method according to the present invention, if the system scale is small, real-time simulation can be achieved even if the transient stability calculation and the power flow/frequency calculation are performed in series. However, in a normal system scale, the power flow calculation and the Real-time simulation will be realized by dividing frequency calculations into separate computers and using high-speed processors such as array processors for transient stability calculations.

〔Effect of the invention〕

As described above, according to the present invention, the operation simulation of the main protection/backup protection relay is realized by using the transient stability calculation as a pace, and even if the trainer makes an erroneous operation during training, the actual It is possible to simulate the movement of the system in the same way as the system, and it has the effect of increasing the training effect.

[Brief explanation of drawings]

FIG. 1 is a processing conceptual diagram of a power system simulation method according to an embodiment of the present invention, FIG. 2 is an operation explanatory diagram based on this processing conceptual diagram, and FIG. 3 is a detailed processing flow diagram of transient stability calculation. FIG. 4 is a processing conceptual diagram of the conventional power system simulation method, and FIG. 5 is a processing flow diagram of power flow/frequency calculation.
11 is a CRT device, 2 is an accident sequence file, and 3 is a Bv condition change data file. In addition, in the figures, the same reference numerals indicate the same or corresponding parts. Patent applicant: Mitsubishi Electric Corporation (2 others) Procedural amendment (voluntary) 1986. ．． 8° - person day

Claims (1)

[Claims] A transient stability calculation program is executed using various data related to power system failures as input data, and the states of the main protection/backup relays and disconnectors as a result of this execution are saved in the SV state change data file. In the power system simulation method, which simulates the operation of the power system by running a power flow/frequency calculation program based on the state change data of the main protection/backup relays and disconnectors output by the change data file, the above main protection - A power system simulation characterized in that a backup protection relay operation simulation is executed based on the above transient stability calculation, and the above power flow/frequency calculation program is executed based on the transient stability calculation result. method.