JP2680166B2 - Power system simulation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a power system simulation method applied to, for example, a training device or the like for maintaining and improving the system operation technology and skills of control personnel. is there.

[Prior Art] Conventionally, as a simulation method of this kind of power system, there is one shown in FIG. In the figure, 1 is a CRT device, 2 is an accident data file storing accident data for accident recovery training, 3 is an SV (ON / OFF information) state change data file, and this SV state change data file 3 is an electric power Operational judgment of various protection relays installed in the system against the voltage and current of each part of the system at the time of an accident, which is obtained from the failure calculation result carried out by inputting the connection relation of system equipment, impedance, generator data and accident data SV which is the operation result judged by performing (system protection relay operation simulation)
Stores state change data.

The SV change data is relay data that operates (operation relay name (No), operation time, operation direction). Trip CB
(Operation CB name (No), operation time, operation direction).

In addition, failure calculation is to find the failure point and the voltage and current of each part of the system when various failures such as 1-line ground fault occur in the equipment in the power system. The target coordinate method is generally used in which the phase is divided into target circuits. Then, with the voltage and current of each part of this system as input,
System protection relay operation judgment (system protection relay operation simulation)
Has been implemented. Reference numeral 4 is an initial system calculation block, 5 is a failure calculation block that simulates the operation of the system protection relay based on the failure calculation result, 6 is a failure occurrence determination block that determines whether a failure has occurred, and 7 is a power flow calculation / frequency calculation block.

Further, FIG. 4 shows a detailed calculation sequence of the power flow calculation / frequency calculation block 7 in FIG. In the figure, 3 is an SV-like variable data file, step ST10 is a switch change determination block that determines switch changes such as circuit breakers, step ST11 is a grid separation calculation block, step ST12 is determination of discontinuous changes such as load shedding. Discontinuous change judgment block, step ST
13 is a power flow calculation block that calculates the power flow for each isolated system,
Step ST14 is a frequency calculation block for calculating the frequency of each separated system, step ST15 is a frequency response relay simulation block for simulating a relay that responds to a frequency such as a frequency lowering relay, and step ST16 is a frequency calculation in increments of ΔT seconds. Repeated n times (= T / ΔT) times, every ΔT second loop, step
ST17 is an overload relay or a relay that operates on power flow or a power flow response relay / control device block that simulates the operation of a relay and control device that responds to system voltage or power flow such as a voltage / reactive power control device, step ST18 is the above step
A real-time synchronization block for performing real-time synchronization with a delay process so that the processing time from ST10 to ST17 is T seconds, and step ST19 is a T second loop for executing power flow / frequency calculation every T seconds.

Next, the operation will be described. First, (A) In the training preparation stage (offline processing), the trainer uses the CRT screen 1
Then, the data such as the failure occurrence time of the system failure, the failure point, and the failure type are set using the light pen (step ST1).
The set data is registered in the accident data file 2 (step ST2). On the other hand, in the initial system calculation 4, power flow calculation is performed by inputting the breaker, disconnector etc. ON / OFF status and generator load setting status set on the CRT screen 1 by the trainer at the training preparation stage (offline processing). Then, the system condition (voltage and power flow at each part of the system) at the training start section is calculated. When calculating the system state, optimization of the initial system state by sharing the generator economic output (ELD function), function simulation of the load tap switching regulator and voltage reactive power control device (LRT and VQC) installed in the transformer Carry out.

Then, if there is a system failure immediately after the start of training, the failure calculation program 5 is executed in advance with the accident data file 2 as input data during the training preparation stage (step ST
3) Then, the system protection relay and trip CB (breaker) that reach the operation are stored in the SV-like variable data file 3 (step ST4).

Next, in (B) training execution stage (online processing), SV
The data stored in the state change data file 3 has an operation time, and the tidal current calculation / frequency calculation block 7 fetches only the data that needs to be reflected in the cycle from the SV state change data file 3. In general, failure calculation and system protection relay operation simulation may take a long time to calculate depending on the type of accident, so failure calculation block 5 and power flow calculation / frequency calculation block 7 including system protection relay operation simulation are performed in parallel. To execute the processing (step ST5). For the system fault immediately after the start of the training, the fault calculation 5 is performed in advance in the training preparation stage (offline processing) of (A), so the fault calculation is not executed and only the power flow calculation / frequency calculation block 7 is executed. The failure calculation block 5 extracts the failure occurrence time, the failure point, and the failure type from the accident data file 2, and determines the failure occurrence at the failure point that has passed the time.

In addition, if the fault point (accident facility) that is occurring is pressurized by operating the trainee, or if the facility during grounding is pressurized by operating the trainee, it is determined that a fault has occurred.

The above-mentioned pressurization means charging the equipment during a power failure by operating a circuit breaker or a disconnector, and the pressurization of the equipment at the point of failure and during grounding causes a failure. If it is determined that a failure has occurred between the time mT and (m + 1) T, the failure occurrence block 6 is determined (step ST6), the failure calculation block 5 is executed, and the operation relay is determined based on the operation simulation of the system protection relay. The trip CB data is stored in the SV state change data file 3 (step ST7).

The above T is the same as T seconds in FIG.
The part marked with a circle in the online processing part in FIG. 3 requires repeated processing after T seconds.

On the other hand, in the power system simulation, as shown in FIG. 3, the power flow calculation / frequency calculation program 7 is executed while taking the trip CB change from the SV change data file 3 in chronological order, and the overload (OL) relay, Simulate the operation of a frequency down (UF) relay or voltage / reactive power control device to simulate a power system.

The detailed operation of the pre-power flow calculation and frequency calculation block 7 will be described below with reference to FIG.

First, the SV change at that time is taken out from the SV change data file 3, the presence or absence of a change in the switch condition is judged by the switch change judgment block (step ST10), and if there is a change, the system separation calculation is executed. Then, determination of the isolated system, correction of the admittance matrix of the system, system capacity for each separated system, total system inertial capacity, etc. are calculated (step ST11). When there is no change, it is determined whether there is a discontinuous change in the active / reactive power of the bus bar due to load shedding or the like (step ST12). When there is a discontinuous change, power flow calculation is executed at the same time as the end of the grid separation calculation block in step ST11 (step ST1
3). When there is no discontinuous change, the frequency calculation block for each separated system is executed at the same time as the end of the power flow calculation block in step ST13 (step ST14), and the simulated block of the relay responsive to the frequency is executed (step ST15). )
Then, these processes are repeated n (= T / ΔT) times.

Next, when these processes are repeated n times, the power flow calculation block at that point is executed (step ST13), and the operation of the overload relay or the system voltage / reactive power control device that responds to the system voltage flow is also performed. Simulate (step ST
17). Finally, a real-time synchronization processing block is executed to synchronize 1 cycle T seconds (step ST18),
The simulation of T seconds is completed (step ST19).
Then, the simulation of the next cycle is started. At this time, when the accident equipment is re-pressurized due to an erroneous operation of the trainee or the equipment is being grounded, the failure calculation is started first. On the other hand, the tidal current / frequency calculation is started when a fixed period (T seconds) has elapsed. Next, a change in the open / closed state of the circuit breaker will be described with reference to FIG. 5, taking re-pressurization of accident equipment due to an erroneous operation as an example.

In FIG. 5, 8 is a power source end busbar, 9 is a power source end circuit breaker CB-B of a power transmission line, 10 is a power transmission line, 11 is a load end circuit breaker CB-A of a power transmission line, 12 is a load end busbar, and 13 is Indicates a permanent failure of the transmission line.

FIG. 5 (a) shows the time at which a permanent failure occurs, and the circuit breakers CB-A and CB-B are both in the closed state (ON). FIG. 5B shows a state in which the failure calculation block is executed, the transmission line relay detects an accident, trips (OFFs) the circuit breaker CB-B, and the failure is removed from the system. Fifth
The figure (c) shows the breaker CB-B
Is turned on and the accident equipment is repressurized (CB-
Both A and CB-B are ON).

In FIG. 5 (d), the failure calculation block is executed again,
The transmission line relay detects an accident, trips (OFF) the circuit breaker CB-B, and the fault is again removed from the system. In FIG. 5 (a) to (d), the circuit breaker CB-A remains ON, but the circuit breaker CB-B
The state of changes from ON to OFF to ON to OFF.

Therefore, if the constant period (T seconds) of the power flow and frequency calculation is between Fig. 5 (c) and (d), the circuit breaker CB-
Since A and CB-B are executed in the ON state, the calculation result is the flow of the tidal current with no accident. On the other hand, in the final state of Fig. 5 (d), the circuit breaker CB-B is tripped and turned off, but if this state is displayed on the system board, the circuit breaker CB-B
Although B is in the OFF state, there is an inconsistent display that the tidal current is flowing without any accident.

[Problems to be Solved by the Invention] Since the conventional power system simulation method is executed as described above, when an accident occurs due to the operation of the trainee, the line power flow and the line breaker state are displayed as described above. There was a problem that contradiction occurred.

The present invention has been made to solve the above problems, and automatically processes the operation of the system protection relay when a failure occurs to automatically determine the trip CB, and when an accident occurs due to an incorrect operation of the trainee. Also aims to obtain a power system simulation method that can simulate the behavior of the power system as in the case of an actual system.

[Means for solving the problem]

The power system simulation method according to the present invention is
Input the power system accident data into the accident data file,
The system failure calculation is executed based on the accident data to simulate the operation of the system protection relay, the states of the system protection relay and the circuit breaker are stored in the SV-like variable data file, and the interruption is performed from the SV-like variable data file. The condition of the system protection relay is taken out in chronological order, power flow calculation and frequency calculation are performed to simulate the operating state of the overload relay and the frequency reduction relay, and the operation simulation of the system protection relay is executed based on the failure calculation. In the method of storing the calculation result in the SV condition data file, the contents of the erroneous operation when an accident occurs due to an erroneous operation are registered in the erroneous operation condition data file, and the accident data registered when the accident occurs due to the erroneous operation is input. After determining the operation of the system protection relay based on the failure calculation, the SV change and the erroneous operation change are used as input data to calculate the power flow and And performs the frequency calculation.

[Action]

The power system simulation method according to the present invention simulates the operation of the system protection relay based on the failure calculation, and stores the result in the SV change data file. By registering the operation details that have become uncertain, and after determining the operation of the system protection relay based on the failure calculation, by executing the tidal current / frequency calculation using the SV change and its erroneous operation change as input data, a system failure due to an erroneous operation of the trainee during training Is simulated like an actual system.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In the figure, the same parts as those in FIGS. 3 to 4 are shown with the same reference numerals, and in FIG. 1, 3a is an erroneous operation change data file storing an accident occurrence due to an operation, and this erroneous operation change data file 3a Corresponding to an erroneous operation resulting in an accident, the erroneous operation breaker name (No) and area data of an accident data file associated with the erroneous operation are stored. 6a is a setting accident determination block that determines the presence / absence of a setting accident, and 6b is a manipulation error determination block that determines the presence / absence of an accident due to an erroneous operation by the trainee,
According to the failure occurrence time stored in the accident data file 2, these determine the failure occurrence at the failure point that has passed the time. 7a is a power flow calculation and frequency calculation block. Further, FIG. 2 is a detailed flow chart of an erroneous operation accident determination block for determining the presence / absence of an accident due to an erroneous operation, a power flow calculation block, and a frequency calculation block in FIG.

Next, the operation will be described. First, in the training preparation stage (offline processing) (A), the trainer displays the CRT screen 1
For the accident data set via, register the accident data in the accident data file 2 (step ST
1). For an accident whose failure occurrence time is set to occur within T ₁ seconds from the start of training, failure calculation is performed at the training preparation stage (offline processing) as an accident that occurs immediately after training (system protection relay operation simulation) Then, the data of the judged operation relay and trip CB is registered in the SV state change data file. For the accident set in the training execution stage (online processing) of (B), the accident data file 2 is imported as input data at the time of the accident occurrence (step
ST6N) The failure calculation is executed by the failure calculation program 5, and the operation of the system protection relay is simulated. As a result, the system protection relay and trip CB that reach the operation are stored in the SV state change data file 3 (step ST7). In the power system simulation, as shown in FIG. 1, the trip CB data stored in the SV-like data file 3 is taken out in chronological order from the SV-like data file 3 (step ST7).
N), power flow calculation and frequency calculation program 7a are executed to simulate the operation of the overload (OL) relay, the frequency drop (UF) relay or the voltage / reactive power control device, and the power system is simulated.

Further, (B) when re-pressurizing the accident equipment due to an erroneous operation of the trainee at the time of training execution or when pressurizing the equipment during grounding, the accident data leading to the system accident due to the erroneous operation is registered in the accident data file 2 (step ST5M ) Together with the erroneous operation contents are registered in the erroneous operation state change data file 3a (step
ST5N). At this time, the erroneous operation condition is the connection relationship of the power system equipment, and the input / off state of the circuit breaker, disconnector, etc. is used as input information. Calculate (Step ST
5P). In addition, the accident data registered when an accident caused by an erroneous operation is input, the failure calculation program 5 is executed (step ST5Q), and the system protection relay operation simulation is performed with the voltage and current of each part of the system of the failure calculation result as input, and the operation determination result Store the operation relay and trip CB data in the SV condition change data file (step ST7), and store the erroneous operation condition registered at the end of the operation determination from the erroneous operation condition change data file (step ST5P). Trip CB (step ST7N) is sequentially reflected from the data file to the power flow calculation and frequency calculation.

〔The invention's effect〕

As described above, according to the present invention, for an accident caused by an erroneous operation when the operation simulation of the system protection relay is performed based on the failure calculation, the erroneous operation state is temporarily evacuated to protect the system based on the failure calculation. After the operation judgment of the relay, it was made to occur in chronological order along with the SV change, so even if an accident occurred due to an erroneous operation of the trainee during training, the open / closed state of the circuit breaker and the power flow value of the transmission line did not conflict.
As in the actual system, the movement of the power system can be simulated and the training effect can be enhanced.

[Brief description of the drawings]

FIG. 1 is an overall process conceptual diagram of a power system simulation method according to an embodiment of the present invention, FIG. 2 is a detailed flow chart of the power flow calculation and frequency calculation of the present invention, and FIG. 3 is a conventional power system simulation method. FIG. 4 is a conceptual diagram of processing, FIG. 4 is a detailed flow chart of conventional power flow calculation and frequency calculation, and FIG. 5 is a diagram for explaining changes in the open / closed state of the breaker at the time of erroneous operation. In the figure, 2 is an accident data file, 3 is an SV state change data file, 3a is an erroneous operation state change data file, 5 is a failure calculation, 7a is a power flow calculation, a frequency calculation, 8 is a power supply end busbar, 9
Is a power line breaker of the transmission line, 10 is a transmission line, 11 is a load end breaker of the transmission line, 12 is a load end busbar, and 13 is a permanent failure of the transmission line. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A power system accident data is input to an accident data file, a system failure calculation is executed based on the accident data to judge the operation of the system protection relay, and the status of the system protection relay and circuit breaker is determined. The changes in the SV change data file are stored in the SV change data file, and the changes in the circuit breaker and system protection relay are extracted from the SV change data file in chronological order to calculate the power flow and frequency and operate the overload relay and frequency drop relay. In the power system simulation method, in which the operation judgment of the system protection relay is executed based on the failure calculation while making the judgment, and the calculation result is stored in the SV-like data file, the contents of the erroneous operation when the accident occurs due to the erroneous operation are erroneously operated. By registering to the condition data file and executing the failure calculation using the accident data registered when the accident occurred due to the above-mentioned erroneous operation as input, Even while executing, the erroneous operation state change and the SV state change that were registered at the end of the operation determination of the system protection relay based on the failure calculation were performed without calculating the erroneous operation state change in the system data. A power system simulation method, characterized in that the power flow calculation and the frequency calculation are performed by using and as input data.