JP2001339862A - Method for stabilizing power system, stabilizing device therefor, and recording medium - Google Patents

Abstract

(57) [Summary] [Problem] When a system failure occurs in a power system and a generator loses synchronism and cannot maintain stability of the power system, the generator that needs to be shut down is disconnected from the power system. Prevent step-out of the generator left in the system and maintain the stability of the power system. When a system failure occurs in a power system, a stabilization method of the power system for shutting down a generator in order to stably maintain the power system 2 incorporates a fault state such as a faulty transmission line and a fault type. Several patterns of the estimated amount of the shut-off generator are selected by the area method, parallel stability calculations are performed based on the standard amount, and the cut-off generator is determined based on the result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of disconnecting a power system from a power system for stabilization when a system failure occurs in the power system and the generator loses synchronism to maintain the stability of the power system. The present invention relates to a power system stabilizing method, a stabilizing device, and a recording medium for determining and shutting down a required generator, thereby preventing a step out of a generator remaining in the power system, and maintaining and maintaining the power system in a stable state. .

[0002]

2. Description of the Related Art When a failure occurs in a power system, the electrical energy that the generator has sent to the power system before the failure is reduced, and the mechanical energy input to the generator does not change suddenly. The generator is accelerated due to the energy imbalance, and when the failure is severe, the generator steps out.
If left unchecked, the other generators will also step out of chain, making it impossible to maintain the power system in a stable manner, which may cause a wide-area blackout.

[0003] In order to prevent such a step-out of the power generator, it is necessary to disconnect the power generator having a large energy imbalance from the power system and balance the energy of the entire power system. Therefore, a stabilizing device that determines a generator that needs to be shut down and shuts down the power generator has been applied to the power grid in order to prevent a chain out-of-step of the generator and maintain the power system stably.

[0004] In this conventional system, in general, the state of the power system, the state of a fault that has occurred in the power system, and the generator that needs to be shut down for stabilization are calculated before the fault and tabulated.
After a failure occurs, the generator is shut off according to this table.

[0005]

By the way, the power system changes moment by moment, and it is necessary to stably maintain the generator or the power system which is out of synchronization depending on the condition of the power system and the state of the fault which has occurred in the power system. Since different generators need to be cut off from the power system, a large number of tables are required before a failure in order to perform high-precision control. The state of the fault includes the fault line, the distance from the substation to the fault point,
There are many unpredictable factors such as fault point resistance and load drop during a fault, and the calculation before the occurrence of a failure (hereinafter referred to as “pre-calculation”) taking all of these factors into consideration depends on the current computer processing capacity. Realistic.

In addition, after the occurrence of a failure, the post-operation method for taking in the failure state, calculating the power system fluctuation, and determining the shut-off generator after the occurrence of the failure is a power system fluctuation calculation for determining the shut-off generator within a limited time. Must be performed the required number of times, which is impractical due to the current processing power of the computer.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and when a system failure occurs in a power system and the generator loses synchronism and cannot maintain stability of the power system, a generator that needs to be shut down To stabilize a power system, and to stabilize and maintain the power system, and to provide a stabilizing method and a recording medium for the power system, wherein And

[0008]

In order to solve the above problems, a method for stabilizing a power system according to claim 1 of the present invention comprises:
When a system failure occurs in a power system, a method for stabilizing the power system that shuts down the generator to maintain the power system in a stable manner. Several patterns are selected for the standard amount of, and the stability calculation is performed in parallel from this standard amount.
It is characterized in that the shutoff generator is determined based on the result.

According to the method for stabilizing a power system according to the first aspect of the present invention, a failure amount such as a faulty transmission line or a fault point resistance is taken in, thereby determining a guide amount of a shut-off generator by a high-precision equal-area method. Becomes possible. In addition, several patterns of the reference amount are selected, the stability calculation is performed in parallel from the reference amount, and the cutoff generator is determined based on the result. Therefore, it is possible to determine the cutoff generator with higher accuracy.

[0010] The method for stabilizing a power system according to claim 2 is as follows.
In the method for stabilizing an electric power system according to the first aspect, when selecting a reference amount of the cut-off generator by the equal area method, the cut-off generator is selected in descending order of the step-out degree.

According to the method for stabilizing the power system according to the second aspect, when selecting the reference amount of the shut-off generator, the stabilizing effect can be further enhanced by selecting the shut-off generator in descending order of the step-out degree. Can be selected.

[0012] A method for stabilizing a power system according to claim 3 is as follows.
In the method for stabilizing an electric power system according to claim 1, when selecting a reference amount of the cut-off generator by the equal area method, frequency control is performed on the assumption that a faulty transmission line is cut off the route and a separated system is generated. And a priority is given to this generator.

According to the power system stabilization method of the third aspect, the transient stability is controlled by giving priority to the cut-off generator for frequency control assuming the occurrence of the separation system. Since the stabilization can be maintained and the frequency fluctuation at the time of generation of the separation system is reduced, the effect of stabilizing the frequency can be enhanced.

According to a fourth aspect of the present invention, there is provided an electric power system stabilizing device.
A power system stabilization device that shuts down a generator to stably maintain the power system when a system failure occurs in the power system. A cut-off generator reference amount determining means for selecting a reference amount of; a cut-off generator pattern determining means for determining a pattern of the cut-off generator from the reference amount of the cut-off generator determined by the cut-off generator reference amount determining means; A stability calculation means for performing stability calculations in parallel from the pattern determined by the cutoff generator pattern determination means, and a cutoff generator determination means for determining a cutoff generator based on the calculation result of the stability calculation means. It is characterized by having.

According to the power system stabilizing device of the fourth aspect, it is possible to stabilize the power system with high accuracy and high speed.

According to a fifth aspect of the present invention, there is provided an electric power system stabilizing device.
In the power system stabilizing device according to claim 4, when the reference amount of the shut-off generator is selected by the equal-area method by the cut-off generator reference amount determining means, the cut-off generator is selected in descending order of the step-out degree. It is characterized in that a cut-off generator selection means is provided.

According to the power system stabilizing device of the fifth aspect, it is possible to efficiently stabilize the power system with a small amount of control.

The power system stabilizing device according to claim 6 is
In the power system stabilizing device according to claim 4, when the reference amount of the cut-off generator is selected by the equal-area method by the cut-off generator reference amount determination means, the faulty transmission line is disconnected from the route and a separated system is generated. In this case, a frequency control target determining means for selecting a shut-off generator for frequency control is provided assuming the case, and the selected generator is prioritized.

According to the power system stabilizing device of the sixth aspect, the effect of stabilizing the frequency when the separated system is generated can be enhanced.

According to a seventh aspect of the present invention, there is provided a computer-readable recording medium in which the processing by the power system stabilizing method according to any one of the first to third aspects is recorded as program data.

According to the recording medium of the present invention, it is possible to provide a recording medium that stabilizes the power system with high accuracy and high speed.

[0022]

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

[First Embodiment] FIG. 1 is a schematic diagram showing a first embodiment of a power system stabilizer according to the present invention.

As shown in FIG. 1, when a failure occurs in a power system 2 which is a target power system and the generator steps out, the stabilizing device 1 loses power in the power system 2. In order to stabilize the power system, the system information 3 is taken in, the generator to be out of synchronization is selected from the generators 4 in the system, and a generator shutoff command 5 is sent to the selected generator to transmit the power system 2. It is to shut off from.

FIG. 2 is a block diagram showing the stabilizing device 1 of FIG.

As shown in FIG. 2, the stabilizing device 1 includes a plurality of measuring terminals 6 installed in a substation, a plurality of control terminals 7 installed in a power plant, and a central device having a CPU 8a and a memory 8b. It is composed of an arithmetic unit 8 and communication lines connecting these units. And the central processing unit 8
In the normal state before the failure, the system information 3 such as the connection state and the power flow state of the power system from the main power supply station 9 is periodically taken in.
1 is taken in through the measuring terminal 6, the electric quantity 12 such as the current I and the voltage V is taken in directly from the measuring terminal 6 as information, and a predetermined operation is performed by the CPU 8 a of the central processing unit 8 using the information. Then, a generator to be cut off necessary for stabilization is determined, a generator cutoff command 5 is sent to the control terminal 7, and the breaker 13 connecting the power generator to the power system 2 is cut off.

FIG. 3 is a flowchart for explaining the function of the CPU of the central processing unit in FIG.

The functions of the power system stabilization method of this embodiment are roughly divided into a pre-calculation means 15, a failure judgment means 16, and a post-calculation / control means 17.

(Preliminary Computation Processing in Step S1) The precomputation processing in step S1 functionally constitutes the precomputation means 15. In this step S1, the connection state of the power system from the main power supply station 9, the power flow state The system information 3 such as system information is periodically taken in, and the current system is recognized and the initial state for the post-calculation is set.

(Failure occurrence determination processing in step S2) The failure occurrence determination processing in the next step S2 functionally constitutes failure determination means 16, and in this step S2, it is determined whether or not a failure has occurred. And when a failure actually occurs,
Recognize the occurrence of a failure and determine the type of failure.

The following steps S3 to S10 functionally constitute the post-calculation / control means 17, which are simplified transient stability calculation processing in step S3, coherent generator discrimination processing in step S4, and step S5. Simplified model creation processing, cut-off generator reference amount determination processing in step S6, cut-off generator pattern determination processing in step S7, step S
8, a detailed transient stability calculation process, a control target device determination process in step S9, and a control command process in step S10.

If it is determined in step S2 that a failure has occurred, an operation for selecting a generator required for stabilization is performed in steps S3 to S10, and a control command is issued to shut off the selected generator. Is sent. Hereinafter, steps S3 to S10 will be described in detail.

(Simplified Transient Stability Calculation Processing in Step S 3) In the simplified transient stability calculation processing in step S 3, the failure mode 11 such as a faulty line, a fault phase, and a fault voltage, and the power system captured by the advance calculation means 15 Using the system information 3 such as the connection state and the power flow state, the transient stability calculation for calculating the power fluctuation of the power system is performed.

At this time, if the transient stability calculation is performed by reducing the system and simplifying the transient stability calculation logic, the calculation speed can be increased.

First, an uncontrolled transient stability calculation that does not simulate a generator shutdown is performed.

FIG. 4 is a diagram showing an example of the result of uncontrolled transient stability calculation in which the transient stability becomes unstable.

In the power system 2, the generators operate synchronously. If the phase angle between the generators exceeds 180 degrees, the generators cannot operate synchronously. Out of sync. When there is a step-out generator, the transient stability is said to be unstable. In the example shown in FIG. 4, the generators G1 and G2 are out of synchronization, and the transient stability is unstable. And, as a result of uncontrolled transient stability calculation,
If the transient stability is stable, there is no need for control, but if the transient stability is unstable, it is necessary to perform control by shutting down the generator.

(Coherent Generator Discriminating Process in Step S4) Next, if the transient stability is unstable, the coherent generator discriminating process in step S4 uses the result of the simple transient stability calculation in step S3 to perform coherent generator. The generator to be driven is extracted. Here, the coherently driven generators are generators that step out together with each other, and in the example shown in FIG. 4, they are the generators G1 and G2.

(Simplified Model Creation Processing in Step S5) The simplified model creation processing in step S5 is based on the transient stability calculation result in the simplified transient stability calculation processing in step S3, and the generator that is driven coherently is one unit. A simplified model (one machine-infinite bus system) is created by reducing to an equivalent generator. The various constants and the initial state quantity (equivalent generator G) of the simplified system model are calculated as follows. Note that n in the equation is the number of coherent generators.

FIG. 5 is a circuit diagram showing a simplified model in which a generator driven coherently is reduced to one equivalent generator.

[0041]

(Equation 1)

(Equation 2)

(Equation 3)

(Equation 4)

(Equation 5)

(Equation 6)

(Equation 7)

(Equation 8)

(Equation 9)

(Process of Determining Guided Amount of Interrupted Generator in Step S6) In step S6, generators to be shut down (hereinafter referred to as "electrically controlled") are selected one by one from among the coherently driven generators, and the area is equal. P-δ when controlled by the law
The curves are calculated one by one, and a control amount (generator cutoff amount) where acceleration energy S1 <deceleration energy S2 is calculated.

FIG. 6 is a diagram showing an example of calculating the P-δ curve when the power is controlled. As shown in FIG. 6, P-
The δ curve changes, and accordingly, the acceleration energy S1 decreases and the deceleration energy S2 increases. If the power control amount is increased and the acceleration energy S1 <the deceleration energy S2, the power system becomes stable, and the power generator up to this time becomes the power control target machine for power system stabilization.

Next, each process in the cutoff generator reference amount determination process in step S6 will be described with reference to the flowchart shown in FIG.

(Calculation of unstable equilibrium point δu in step S6-1)

(Equation 10)

[0046]

[Equation 11]

(Acceleration energy S1 in step S6-2)
Calculation process)

(Equation 12)

(Deceleration energy S2 in step S6-3)
Calculation process)

(Equation 13)

(Acceleration energy S1 in step S6-4)
Comparison processing between step S6-2 and deceleration energy S2) is compared using the processing result of step S6-2 and the processing result of step S6-3.

(Stable at step S6-5 (S1 <S2)
Is determined in step S6-5 (S1 <S
2) Determine whether it is unstable (S1> S2). If the vehicle is unstable, the process returns to step S6-3 to calculate the deceleration energy S2 after the electric control, and determine the stability or instability again using the result. Until stable (S1 <S2)
The arithmetic processing of steps S6-1 to S6-4 is repeated.

[0051]

[Outside 1]

(Shutdown Generator Pattern Determination Process in Step S7) FIG. 8 shows the pattern of the shutdown generator pattern based on the reference amount of the shutdown generator for stabilizing the transient stability determined in the shutdown generator reference amount determination process. It is an explanatory view for making a decision.

FIG. 8 shows an example in which the generators that step out coherently are G1,... G8, and the power control order is G1,. As a result of the calculation based on the equal area method in the cutoff generator reference amount determination process in step S6 shown in FIG. 3, when the generators G1,.
When it is stable to control up to G6, the power control pattern for the detailed transient stability calculation processing in step S8 may be, for example, a pattern that controls power to the generators before and after the stability limit indicated by ★.

[0054]

[Outside 2]

(Detailed Transient Stability Calculation Processing in Step S8) The cut-off generator for stabilizing the cut-off generator reference amount determination processing in step S7 is a guide, and the power control determined in the cut-off generator pattern determination processing. The detailed transient stability calculation is performed in the detailed transient stability calculation processing of step S8 using the pattern. In the present embodiment, pattern 1, pattern 2, pattern 3,
And a detailed transient stability calculation of a total of four patterns of pattern 4. In order to increase the speed, it is desirable to perform the detailed transient stability calculation in parallel.

(Electrically Controlled Machine Determination Process in Step S9) In the electrically controlled device determination process in step S9, the transient stability is stable based on the result of the detailed transient stability calculation performed for each pattern in step S8. The power control pattern having the minimum control amount is determined as the power control target machine.

In this embodiment, pattern 1 and pattern 2
Is unstable and the patterns 3 and 4 are stable, the pattern 3 having the minimum control amount is determined from the patterns 3 and 4 as the electric control target machine.

(Control Command Processing in Step S10) In the power control target machine determination processing in step S9, a generator shutoff command is sent to the calculated power control target machine.

Here, in the flowchart shown in FIG. 3, the cut-off generator reference amount determination processing in step S6 is performed to stabilize the transient stability by the equal area method taking in the fault state such as the faulty transmission line and the fault type. The reference amount of the cut-off generator is selected, and the cut-off generator reference amount determination means 18 is configured as a function.

Further, the cut-off generator pattern determination processing of step S7 determines the cut-off generator pattern from the reference amount of the cut-off generator determined by the cut-off generator reference amount determining means 18, and has a function of the cut-off generator pattern. The determining means 19 is constituted.

Further, in the detailed transient stability calculation processing of step S8, the stability calculation is performed in parallel from the electric control pattern determined by the shutoff generator pattern determination means 19,
The stability calculating means 20 is configured as a function. Then, the electronically controlled device determining process in step S9 is performed by the stability calculating means 2
The cut-off generator is determined based on the calculation result of 0, and the cut-off generator determining means 21 is configured as a function.

Further, in the present embodiment, steps S1 to S1
The means for executing S10 is stored in advance in the memory 8b of the central processing unit 8 as program data.
Constitutes the recording medium of the present invention, and examples of the recording medium include a portable medium such as a semiconductor memory, a hard disk, and a CD-ROM.

As described above, according to the power system stabilization method of the present embodiment, the reference amount of the cut-off generator for stabilizing the transient stability by the equal area method taking in the fault state such as the faulty transmission line and the fault type. Are selected in parallel, stability calculations are performed in parallel from the estimated amount, and the shutoff generator is determined based on the results.

Therefore, according to the power system stabilizing method of the present embodiment, by taking in the fault state such as the faulty transmission line and the fault point resistance, the reference amount of the shut-off generator by the high-precision equal area method is obtained. A decision can be made. In addition, several patterns of the reference amount are selected, the stability calculation is performed in parallel from the reference amount, and the cutoff generator is determined based on the result. Therefore, it is possible to determine the cutoff generator with higher accuracy.

Further, in the power system stabilizing device of the present embodiment, the memory 8 b for stabilizing the power system is incorporated in the central processing unit 8. Based on the system information 3 periodically transmitted from the main power supply station 9, a pre-operation is performed in the pre-operation means 15 of the memory 8 b for stabilizing the power system 2, and the failure state 11 transmitted from the measurement terminal 6, Recognition of the occurrence of the failure or the state of the failure from the electric quantity 12, a post-calculation / control means 17 of the memory 8 b for stabilizing the electric power system performs a calculation for determining an electric control target machine, and
A generator shutoff command 5 is sent to the corresponding generator, and the generator is shut off.

That is, according to the power system stabilizing device of the present embodiment, the reference amount of the shut-off generator for stabilizing the transient stability by the equal area method taking in the fault state such as the faulty transmission line and the fault type. And a cut-off generator pattern determining means 19 for determining a pattern of the cut-off generator from the reference amount of the cut-off generator determined by the cut-off generator reference amount determining means 18. A stability calculating means 20 for executing stability calculation in parallel from the power control pattern determined by the cut-off generator pattern determining means 19, and a cut-off generator for determining a cut-off generator based on the calculation result of the stability calculating means 20 The provision of the determination unit 21 makes it possible to stabilize the power system with high accuracy and high speed.

Further, the recording medium of the present embodiment has a memory 8b which can be read by the CPU 8a and records the processing by the power system stabilization method of the present embodiment as program data.
Accordingly, it is possible to provide a recording medium that stabilizes the power system with high accuracy and high speed.

[Second Embodiment] FIG. 9 is a flowchart for explaining the function of the CPU of the central processing unit in the second embodiment of the power system stabilizer according to the present invention. In FIG. 9, the same processing as the processing shown in FIG. 3 is denoted by the same step number, and the duplicate description will be omitted. The same applies to the following embodiments.

In the present embodiment, as shown in FIG. 9, a simplified model creation process of step S5 which functionally constitutes a part of the post operation / control means 17 in FIG.
Step S5A during the process of determining the reference amount of the shut-off generator
Is newly added.

The power control priority determining process in step S5A functionally constitutes the shut-off generator selecting means 22. In the shut-off generator guide amount determining process in step S6, the coherently driven generators are selected. P-δ when electrifying generators are selected one by one and electrified by the equal area method
The curves are calculated one by one, and a control amount (generator cutoff amount) where acceleration energy S1 <deceleration energy S2 is calculated.

Here, when selecting generators to be controlled one by one, it is effective to select generators that are effective for stabilization. In other words, it is effective to select a generator with a large step-out degree.

FIG. 10 is a diagram for explaining the shutoff generator selection means 22 according to the second embodiment of the present invention.

The magnitude of the step-out level is one as shown in FIG.
It can be seen from the difference in the phase angle of the generator as shown in FIG. It is generally considered that a generator with a larger phase angle loses synchronization earlier. Therefore, it is effective to determine the step-out determination threshold value and select a generator that has exceeded the step-out determination threshold value 23 quickly.

That is, in FIG. 10, the generators G1,
In the order of the generator G2, the step-out determination threshold value 23 is exceeded,
The step-out degree is in the order of the generator G1 and the generator G2, and the power control priority is in the order of the generator G1 and the generator G2.

There is also a method in which acceleration energy is used as the degree of the step-out. Since a generator having a larger acceleration energy has a larger amount of unstable energy, the magnitude of the step-out can be determined by the magnitude of the generator.

The acceleration energy of each generator is
It can be calculated by equation (14). Δωtc is the expected power control time tc
Is the angular velocity deviation Mi of the generator i.

[0077]

[Equation 14]

Therefore, the control priority is determined in descending order of the acceleration energy calculated by the equation (14). According to the power control priority determined in the power control priority determination processing in step S5A, the cutoff generator reference amount determination processing in step S6 determines the power control target generator. Other processing is shown in FIG.
Since the processing is the same as that of the first embodiment shown in FIG.

In this embodiment, the means for executing steps S1 to S10 are stored in advance in the memory 8b of the central processing unit 8 as program data as in the first embodiment.

As described above, according to the power system stabilization method of the present embodiment, when selecting the reference amount of the cut-off generator for stabilizing the transient stability by the equal area method in the first embodiment,
By selecting the shut-off generator in the order of the step-out degree, it is possible to select a control object having a higher stabilizing effect.

Further, according to the power system stabilizing apparatus of the present embodiment, when selecting the reference amount of the cut-off generator for stabilizing the transient stability by the equal area method in the first embodiment, the power generation system must By providing the cut-off generator selection means 21 for selecting the cut-off generator in descending order of the keying degree, the power system can be efficiently stabilized with a small amount of control.

Further, as in the first embodiment, the recording medium of the present embodiment has a CPU 8 in which the processing by the power system stabilization method of the present embodiment is recorded as program data.
By using the memory 8b readable by a, it is possible to select a control object having a higher stabilization effect, and to provide a recording medium for stabilizing the power system.

[Third Embodiment] FIG. 11 is a flowchart for explaining the function of the CPU of the central processing unit in the third embodiment of the power system stabilizing apparatus according to the present invention.

FIG. 11 is a flow chart shown in FIG. 9. In the case of a failure that may cause the occurrence of the separation system in step S2A, it is assumed that the separation system has occurred, and the control target of the frequency control for the separation system is defined as a step. A routine is added in which the power control priority is calculated in advance in the separation system frequency control target determination processing in S2B, and the power control priority is determined in the power control priority determination processing in step S5A with priority given to this frequency control control target.

By the way, whether or not a separation system occurs is determined by
It depends on the failure mode 11 such as the faulty transmission line and the faulty phase. Also,
In the case of a failure accompanied by reclosing, it depends on whether the reclosing succeeds or fails. If the re-closure fails and the route is cut off and the main system is isolated, a separation system is generated. When this separation system occurs and the balance between power generation and load, that is, supply and demand imbalance occurs, the separation system The frequency after the occurrence rises or falls sharply. When the amount of power generation is larger, the frequency rises sharply, and when the amount of load is larger, the frequency falls sharply. In order to prevent this and stabilize the frequency, frequency control for shutting down the generator or load has been conventionally performed.

However, if the amount of supply and demand imbalance is large, the degree of sudden increase or fall of the frequency until the generator is cut off or the load is cut off is large, making frequency control difficult and increasing the amount of control by additional control. May occur.

In order to prevent these problems, it is desirable for the frequency control to minimize the supply-demand imbalance when the separation system is generated.

Therefore, in the present embodiment, when there is a possibility of occurrence of a separated system from the failure mode 11, the simplified transient stability calculation processing in step S3, the coherent generator determination processing in step S4, and the simplified processing in step S5 In parallel with the model creation processing, the separation system frequency control target determination processing in step S2B is performed.

In the separation system frequency control target determination processing in step S2B, the generation of the separation system is assumed, and the frequency control target after the generation of the separation system is determined. Usually, a control target that matches the supply-demand imbalance amount is selected. This separation system frequency control target determination processing functionally constitutes frequency control target determination means 24. Then, the control target selected by the separation system frequency control target determination processing is determined in step S5A.
Is sent to the power control priority determination process.

In the control priority determination process of step S5A, the control target selected by the separated system frequency control target determination process of step S2B is prioritized to determine the priority of power control. In other words, in the power control priority determination process of step S5A, the order of the generators to be controlled out of the coherently out-of-step generators is determined. When the generator selected by the determination process is included, the priority of the generator is determined by giving priority to this. Thereby, when a separation system is generated, the frequency fluctuation is reduced, and the stabilization of the frequency is easily maintained.

In this embodiment, the means for executing steps S1 to S10 are stored in advance in the memory 8b of the central processing unit 8 as program data as in the first embodiment.

As described above, according to the power system stabilization method of the present embodiment, when selecting the reference amount of the cut-off generator for stabilizing the transient stability by the equal area method in the first embodiment,
Assuming that a faulty transmission line is cut off the route and a separation system is generated, a cutoff generator for frequency control is selected, and this generator is given priority. Therefore, by performing the transient stability control giving priority to the shut-off generator for frequency control assuming the occurrence of the separation system, it is possible to maintain the stability of the transient stability, and at the time of the occurrence of the separation system, Since the frequency fluctuation is reduced, the effect of stabilizing the frequency can be increased.

Further, according to the power system stabilizing device of the present embodiment, when selecting the reference amount of the cut-off generator for stabilizing the transient stability by the equal area method in the first embodiment, a failure occurs. Assuming a case where the generated transmission line is disconnected from the route and a separated system is generated, a cutoff generator for frequency control is selected, and a frequency control target determining unit 24 for giving priority to this generator is selected.
Is provided, in addition to the effect of the second embodiment,
It is also possible to enhance the effect of stabilizing the frequency when the separation system is generated.

Further, the recording medium according to the present embodiment has the same structure as that of the first and second embodiments except that the processing by the power system stabilization method according to the present embodiment is recorded as program data.
By using the memory 8b readable by the PU 8a, the effect of stabilizing the frequency when the separation system is generated can be enhanced, and a recording medium for stabilizing the power system can be provided.

[0095]

As described above, according to the present invention, a failure generator state, such as a faulty transmission line or a fault point resistance, is taken in, and a reference amount of a cut-off generator for stabilizing transient stability by an equal area method. By selecting several patterns and determining the shut-off generator by the confirmation calculation based on the stability calculation, it is possible to determine the standard amount of the shut-off generator by the high-precision equal-area method. In addition, several patterns of the reference amount are selected, the stability calculation is performed in parallel from the reference amount, and the cutoff generator is determined based on the result. Therefore, it is possible to determine the cutoff generator with higher accuracy.

In addition, since the stabilizing method takes into account a fault state such as a faulty transmission line and a fault point resistance, it is possible to control the power system with extremely high accuracy. Thus, the problem of over-control and under-control is reduced, and the total control amount is reduced in consideration of the problem of additional control in the case of under-control. Also,
A high stabilizing effect can be expected by proper control.

Further, the control assuming the occurrence of the separation system allows not only a high stabilizing effect at the time of occurrence of the separation system, but also
This has the effect of reducing the total control amount for the transient stability and the frequency stability at the time of generation of the separation system.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a first embodiment of a power system stabilizer according to the present invention.

FIG. 2 is a configuration diagram showing the stabilizer of FIG. 1;

FIG. 3 is a flowchart for explaining functions of a CPU of the central processing unit in FIG. 2;

FIG. 4 is a diagram showing an example of a result of uncontrolled transient stability calculation in which the transient stability becomes unstable.

FIG. 5 is a circuit diagram showing a simplified model in which a generator driven coherently is reduced to one equivalent generator.

FIG. 6 is a diagram showing a calculation example of a P-δ curve when the electric power is controlled.

FIG. 7 is a flowchart showing each process in a cutoff generator reference amount determination process.

FIG. 8 is an explanatory diagram for determining a pattern of the shut-off generator from the standard amount of the shut-off generator for stabilizing the transient stability determined in the cut-off generator standard amount determination process.

FIG. 9 is a flowchart for explaining the function of the CPU of the central processing unit in the second embodiment of the power system stabilizing device according to the present invention.

FIG. 10 is an explanatory diagram showing an electrical control priority determination process according to the second embodiment.

FIG. 11 is a flowchart for explaining functions of a CPU of a central processing unit in a third embodiment of the power system stabilizing device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stabilizer 2 Power system 3 System information 4 Generator in system 5 Generator shutoff command 6 Measurement terminal 7 Control terminal 8 Central processing unit 8a CPU 8b Memory 9 Main power supply station 10 Relay panel 11 Failure state 12 Electricity 13 Breaker 15 Pre-calculation means 16 Failure determination means 17 Post-calculation / control means 18 Cut-off generator reference amount determination means 19 Cut-off generator pattern determination means 20 Stability calculation means 21 Cut-off generator determination means 22 Cut-off generator selection means 23 Step-out determination Threshold value 24 Frequency control target determination means

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Hisayuki Kobayashi 1 in Higashi-ku, Higashi-ku, Nagoya, Aichi Prefecture Inside Chubu Electric Power Co., Inc. (72) Inventor Yoshihiko 1 in Higashi-ku, Higashi-ku, Nagoya, Aichi Prefecture Chubu Electric Power Co., Inc. In-house (72) Inventor Koichi Yokoi 1 Higashi-Shinmachi, Higashi-ku, Nagoya City, Aichi Prefecture Inside Chubu Electric Power Co., Inc. (72) Inventor Yasuhiro Taguchi 1 Toshiba Town, Fuchu City, Tokyo Toshiba Corporation Fuchu Plant (72) Inventor Shigeru Sato 1-1-1, Shibaura, Minato-ku, Tokyo, Tokyo, Japan Toshiba Corporation Head Office (72) Inventor Hiromasa Shirai 1-1-1, Shibaura, Minato-ku, Tokyo, Tokyo Toshiba Corporation Headquarters Office (72) Inventor Takeshi Kaneko 1F Toshiba-cho, Fuchu-shi, Tokyo F-term in the Fuchu factory of Toshiba Corporation (reference) 5G066 AA03 AD01 AD09 AE09

Claims (7)

[Claims] In a method for stabilizing a power system, in which a generator is shut down in order to stably maintain the power system when a system failure occurs in the power system, an equal area including a fault state such as a faulty transmission line and a fault type. A method for stabilizing an electric power system, comprising selecting several patterns of reference amounts of a shut-off generator by a method, performing parallel stability calculations from the reference amounts, and determining a cut-off generator based on the results. 2. The method for stabilizing an electric power system according to claim 1, wherein a reference amount of the shut-off generator is selected by an equal area method.
A method for stabilizing an electric power system, comprising selecting a shut-off generator in descending order of a step-out degree. 3. The method for stabilizing a power system according to claim 1, wherein when selecting a reference amount of the shut-off generator by the equal area method,
A method for stabilizing an electric power system, comprising calculating a shut-off generator for frequency control on the assumption that a faulty transmission line is disconnected from a route and causing a separation system, and giving priority to this generator. 4. A stabilizing device for a power system that shuts down a generator to stably maintain the power system when a system fault occurs in the power system, wherein the equal area includes a fault state such as a faulty transmission line and a fault type. A cut-off generator reference amount determining means for selecting a reference amount of the cut-off generator by the method, and a cut-off generator determining a cut-off generator pattern from the reference amount of the cut-off generator determined by the cut-off generator reference amount determining means. Pattern determining means, stability calculating means for performing stability calculations in parallel from the patterns determined by the shut-off generator pattern determining means, and shut-off generator for determining the shut-off generator based on the calculation results of the stability calculating means A stabilizing device for an electric power system, comprising: a determination unit. 5. The stabilizing device for a power system according to claim 4, wherein when the reference amount of the shut-off generator is selected by the equal-area method by the cut-off generator guide amount determining means, the shut-down is performed in descending order of the step-out degree. An electric power system stabilizing device, further comprising a cut-off generator selecting means for selecting a generator. 6. The stabilizing device for an electric power system according to claim 4, wherein when the reference amount of the shut-down generator is selected by the equal-area method by the cut-off generator reference amount determining means, the route of the faulty transmission line is disconnected. A power system stabilizing device, wherein a frequency control target determining means for selecting a shut-off generator for frequency control is provided on the assumption that a separated system is generated, and the selected generator is prioritized. . 7. A computer-readable recording medium in which a process by the power system stabilizing method according to claim 1 is recorded as program data.