JP2760750B2 - Electric station operation support device and accident / failure inference method used for the same - Google Patents

Abstract

PURPOSE:To obtain a system for supporting the operation at an electric station through application of AI based on the encoded knowledge of expert in which the time required for determining the content of fault on a power system and the content of operation/failure of a power system protector/controller is shortened. CONSTITUTION:An inferring method generating means 22 previously analyzes the collation matching form of the enumerated events 211 of expert knowledge which may take place upon occurrence of fault on a power system and automatically generate a method for determining the fault on a power system quicker than a method where the expert knowledge is collated as it is.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substation operation support device for judging the details of an accident in a power system and the operation and failure of a power system protection / control device when an accident occurs in a power system, and outputting a judgment result. It is related to the accident / failure inference method used for it.

[0002]

2. Description of the Related Art In order to ensure the reliability of power supply, it is important to respond quickly in the event of an accident, and to quickly and accurately determine the details of an accident in a power system and the operation of a power system protection / control device. In addition, an electric station operation support device that outputs a determination result is required.

FIG. 8 is a block diagram showing an electric station operation support apparatus described in "Electric Site Technology" published on May 5, 1988 by Electric Information Co., Ltd., pp. 5-9. In FIG. 8, reference numeral 1 denotes input information at the time of occurrence of an accident in the power system. The information includes system state information such as a switch state and a charge / discharge state in the power system, operation information of a protection relay of the power system, and the like. And the operation information of the power system protection / control device. 2 is an electric station operation support device, and 211 is an expert knowledge about the power system and the power system protection / control device. It is an enumeration case of a combination case. Reference numeral 24 denotes a comparison / matching means prepared as an inference engine based on expert knowledge, and compares and matches the input information 1 and the enumerated examples 211 in order. Reference numeral 3 denotes a comparison / matching determination result output from the comparison / matching unit 24.

FIG. 9 is a block diagram showing a power system and a power system protection / control device used by the electric station operation support device. In FIG. 9, 91A, 91B, 91C, 91
D, 91E, 91F, 91G are electric conductors constituting a power system, 92A, 92B are circuit breakers, 93A, 93B, 93
C, 93D, 93E are disconnectors, 94A, 94B, 94C
Is a current sensor, 95 is a voltage sensor, 96 is a transmission line main protection relay, 97 is a transmission line backup protection relay, 98 is a bus protection relay, 10 is a protection range of the transmission line main protection relay 96, 1
Reference numeral 1 denotes a protection range of the bus protection relay 98. Here, the electric conductors 91A and 91B, which are transmission lines, are charged,
As an example of a general operation mode connected to the electric conductor 91D which is a bus, the disconnector 93A, the circuit breaker 92A, and the disconnector 93B are in the ON state, the disconnector 93D is in the OFF state, the disconnector 93C, the circuit breaker 92B, and the disconnector. It is assumed that the state of the container 93E is undefined.

The protection range 10 of the transmission line main protection relay 96
If a power system accident such as a short circuit or ground fault occurs,
First, the transmission line main protection relay 96 operates to turn off the circuit breaker 92A from the current information and the like from the current sensor 94B. However, when the transmission line main protection relay 96 does not operate or the like, the transmission line back-up protection relay 97 is activated by the current sensor 9.
The circuit breaker 92A is turned off by determining that the accident has continued for a predetermined time based on the current information from the 4B, the voltage information from the voltage sensor 95, and the like.
To When a power system accident such as a short circuit or a ground fault occurs in the protection range 11 of the bus protection relay 98, based on the current information from the current sensors 94A and 94C,
The busbar main protection relay 98 operates to turn off the circuit breakers 92A and 92B.

Next, an enumeration example 211 of a combination example of assumed power system accidents and operation / failure contents of the power system protection / control device and input information will be described with reference to FIG. 9 and FIG. In FIG. 9, 12A is an electric conductor 91A or current sensor 94A and disconnector 93A.
12B indicates that any of the electric conductors 91B is an accident site, and 12B indicates that the electric conductor 91B between the current sensor 94A and the circuit breaker 92A is an accident site.
2C indicates that the electric conductor 91C between the current sensor 94B and the circuit breaker 92A is the accident site, and 12D indicates the electric conductor 91C or the electric conductor 91D or the electric conductor between the current sensor 94B and the disconnector 93A. 91E or an electric conductor 91F between the current sensor 94C and the circuit breaker 92B.
Indicates that this is the accident location. FIG.
In the figure, 211A is a specific example of the enumerated example 211, and the input items are the state of the circuit breakers 92A and 92B and the operation information of the transmission line main protection relay 96, the transmission line rear protection relay 97, and the bus protection relay 98. Vessels 92A, 92
The attribute value that B can take is OFF after accident or O after accident.
In the N state, the possible attribute values of the transmission line main protection relay 96, the transmission line backup protection relay 97, and the bus protection relay 98 are active or inactive.

Next, each case of an accident / failure in the power system will be described with reference to FIGS. 9 and 10. FIG. (1) First, the location of the accident 1
2A is assumed to have occurred outside the protection range 10 of the transmission line main protection relay 96 and outside the protection range 11 of the bus protection relay 98, so that the transmission line main protection relay 96 operates and the circuit breaker 9
2A is cut off, the accident is eliminated, the transmission line back-up protection relay 97 and the bus protection relay 98 do not operate, and the circuit breaker 92
The state of B is the system state after the occurrence of the accident, which does not change. That is, at the time of a system failure, the transmission line main protection relay 96 operates, the circuit breaker 92A is shut off, the accident is eliminated, the transmission line back-up protection relay 97 and the bus protection relay 98 do not operate, and the state of the circuit breaker 92B is changed. If it does not change, it can be concluded that there is a possibility of the accident location 12A of the power system accident / failure content as the accident location. This accident removal process,
Expressing the combination example of the power system accident / failure content and the operation / failure content of the power system protection / control device, in enumeration example 211A, the row on the accident / failure content is one case, and the accident / failure content is If a fault occurs, the circuit breaker 92A is turned off after the accident,
Regardless of the state of B, the transmission line main protection relay 96 is operating, the transmission line back-up protection relay 97 is inactive, and the bus protection relay is inactive. That is, the circuit breaker 92A is cut off at the time of a system fault and is turned off after the fault, the transmission line main protection relay 96 operates, and the transmission line rear protection relay 97
Is inactive and the bus protection relay 98 is inoperative, it can be concluded that there is a possibility of accident / failure content as the accident / failure content. (2) Similarly, the fault location 12B of the power system fault / failure is located within the protection range 10 of the transmission line main protection relay 96 and the protection range 11 of the bus protection relay 98,
A, it is assumed that this occurred on the power supply side of A, so that the transmission line main protection relay 96 and the bus protection relay 98 operate and the circuit breaker 9
2A and 92B are cut off, the accident is eliminated, and the transmission line rear protection relay 97 is in a non-operating state after the occurrence of the accident. That is, at the time of a system failure, the transmission line main protection relay 96
And the bus protection relay 98 operates, and the circuit breakers 92A, 9
If 2B is cut off, the accident is eliminated, and the transmission line back-up protection relay 97 is inoperative, it can be concluded that there is a possibility that the accident point is an accident point 12B of an accident / failure content of the power system. This process of eliminating accidents is described as
Expressing in a combination example of the failure content and the operation / failure content of the power system protection / control device, in enumeration example 211A, the row related to the accident / failure content is one case, and when the accident / failure content occurs, , Circuit breaker 92
A and 92B are cut off and turned off after the accident, the transmission line main protection relay 96 operates, the transmission line rear protection relay 97 does not operate, and the bus protection relay 98 operates. That is, at the time of a system failure, the circuit breaker 92A and the circuit breaker 9
2B is OFF after the accident, the transmission line main protection relay 96 operates, the transmission line rear protection relay 97 does not operate, and the bus protection relay 98 operates.
It is possible to conclude that there is a possibility of an accident or failure. (3) Similarly, the fault location 12C of the power system fault / failure content is within the protection range 10 of the transmission line main protection relay 96 and the protection range 11 of the bus protection relay 98, and
A, the transmission line main protection relay 96 and the bus protection relay 98 operate, and the circuit breaker 92A
And the circuit breaker 92B are shut off, the accident is eliminated, and the transmission line rear protection relay 97 is inoperative. That is, at the time of a system failure, the transmission line main protection relay 9
7 and the bus protection relay 98 operate, the circuit breaker 92A and the circuit breaker 92B are cut off, the accident is eliminated, and if the transmission line rear protection relay 97 is not operated, the accident / failure of the power system is regarded as an accident site. It can be determined that there is a possibility of the accident location 12C of the content. This accident elimination process is based on the details of the power system accident / failure and the operation / operation of the power system protection / control device.
In terms of a combination example with failure details, enumeration example 2
In 11A, a row related to the accident / failure content is one example, and when the accident / failure content occurs,
The circuit breaker 92A and the circuit breaker 92B are cut off and turned off after the accident, the transmission line main protection relay 96 operates, the transmission line rear protection relay 97 does not operate, and the bus protection relay 98 operates. That is, at the time of a system fault, if the circuit breakers 92A and 92B are OFF after the fault, the transmission line main protection relay 96 is operating, the transmission line rear protection relay 97 is inactive, and the bus protection relay 98 is operating, The accident
It is possible to conclude that there is a possibility of an accident or failure as the failure content. (4) Similarly, since it is assumed that the fault location 12D of the power system fault / failure occurred outside the protection range 10 of the transmission line main protection relay 96 and within the protection range 11 of the bus protection relay 98, the bus protection is performed. The relay 98 is activated and the circuit breaker 92
A and the circuit breaker 92B are cut off, the accident is eliminated, and the transmission line main protection relay 96 and the transmission line back-up protection relay 97 are inoperative state after the occurrence of the accident. That is, at the time of a system failure, if the bus protection relay 98 operates, the circuit breaker 92A and the circuit breaker 92B are shut off, the accident is eliminated, and the transmission line main protection relay 96 and the transmission line rear protection relay 97 are inoperative. It can be concluded that there is a possibility of the accident location 12D of the accident / failure of the power system as the accident location. If this accident removal process is expressed by a combination example of the accident / failure content of the power system and the operation / failure content of the power system protection / control device, in the enumeration example 211A, the row related to the accident / failure content is one case. Yes, when an accident or failure occurs, the circuit breaker 92A and the circuit breaker 92B are shut off and turned off after the accident, the transmission line main protection relay 96 does not operate, and the transmission line rear protection relay 97 does not operate. This indicates that the bus protection relay 98 is in operation. That is, at the time of a system fault, the circuit breakers 92A and 92B are turned off after the fault, the transmission line main protection relay 96 does not operate, the transmission line rear protection relay 97 does not operate, and the bus protection relay 98 does not operate.
If the device is operating, it can be concluded that there is a possibility of the content of the accident or failure as the content of the accident or failure. (5) Similarly, it is assumed that the accident location 12A of the power system accident / failure occurred within the protection range 10 of the transmission line main protection relay 96 and outside the protection range 11 of the bus protection relay 98. Since the main protection relay 96 is malfunctioning, the transmission line back-up protection relay 97 operates and the circuit breaker 92A
Is cut off, the accident is eliminated, the bus protection relay 98 is inactive, and the state of the circuit breaker 92B does not change. That is, at the time of a system fault, the transmission line back-up protection relay 97 operates, the circuit breaker 92A is shut off, the fault is eliminated, and if the transmission line back-up protection relay 97 and the bus protection relay 98 do not operate, the power is regarded as an accident location. It can be concluded that there is a possibility of the accident location 12A in the system accident / failure content. If the process of removing the accident is expressed by a combination example of the details of the accident / failure of the power system and the operation / failure of the power system protection / control device, enumeration example 21
In FIG. 1A, a row related to the details of the accident / failure is one example. When the details of the accident / failure occur, the circuit breaker 92A is shut off and turned off after the accident.
Regardless of the state of B, the transmission line main protection relay 96 is inactive, the transmission line back-up protection relay 97 is operating, and the bus protection relay 98 is inoperative. That is, at the time of a system fault, if the circuit breaker 92A is OFF after the fault, the transmission line main protection relay 96 is inactive, the transmission line rear protection relay 97 is operating, and the bus protection relay 98 is inoperative, the fault It is possible to conclude that there is a possibility of an accident or failure as the failure content. In general, the above list of cases is one of the forms of expression of expert knowledge regarding the power system and the power system protection / control device, and the expert prepares this,
A code form that can be processed by a computer is provided in the substation operation support device.

Next, the operation of the conventional electric station operation support device will be described. In FIG. 8, in order to judge the details of the accident / failure from the input information 1 obtained at the time of the occurrence of the power system accident, the comparison and comparison between the input information 1 and the cases of the enumerated cases 211 are performed in order from the beginning of the enumerated cases 211. Then, a case that is detected from the enumerated cases 211 and matches the input information 1 obtained at the time of occurrence of the power system accident is output as the accident status determination result 3 of the input information 1.

[0009]

As described above, the conventional substation operation support device is configured to compare and match input information at the time of occurrence of an accident with the enumerated cases 211 in order from the beginning of the enumerated cases 211. In order to express the expert knowledge of the power grid and power grid protection and control equipment in detail,
As the number of enumerated cases increases, there is a problem that the time spent until a matching case can be detected increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to analyze in advance a collation form of a group of expert knowledge, which can occur when an electric power system accident occurs, and to analyze the power system accident. When an error occurs, the content of the accident and the operation / failure of the device are determined at high speed.

[0011]

According to a first aspect of the present invention, there is provided an electric-station operation support apparatus according to a first aspect of the present invention, which analyzes in advance a collation form of a group of expert knowledge, which can occur when an accident occurs in a power system. This system has means for automatically generating a method of inferring the accident / failure content of a system input item at the time of an accident, which is smaller in the number of times of comparison and judgment than when the input information at the time of the accident is directly collated with the enumerated cases.

According to the second aspect of the present invention, the accident / failure inference method used in the electric station operation support apparatus according to the second invention is a collation type inference method until the number of cases can be limited to one, or By limiting the cases where the entropy index stops decreasing until the decrease stops, the content of the accident / failure of the input item at the time of occurrence of the accident is inferred.

According to a third aspect of the present invention, there is provided an electric station operation support device, comprising:
A means for expressing a failure content inference method using a tree structure is provided.

[0014]

According to the first aspect of the present invention, the substation operation support apparatus analyzes in advance the form of knowledge group verification that can occur when a power system accident occurs, and compares the input information at the time of the accident with the enumerated cases as they are. Since the number of comparison determinations is smaller than that in the case of collation, an electric station operation support device capable of quickly determining the details of an accident and the operation / failure of the device when an accident occurs in the power system is realized.

The inference method according to the second aspect of the present invention is to limit the number of established cases by classification until the number of cases can be limited to one or until the decrease of the entropy index stops. An electric station operation support device capable of determining the details of an accident and the operation / failure of the device at high speed is realized.

The electric station operation support device according to the third aspect of the present invention expresses, using a tree structure, a method of inferring the contents of an accident or a failure of an input item at the time of occurrence of an accident, thereby providing a description of the contents of the accident and the operation or failure of the device. The determination process is easily understood visually.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. Example 1 (corresponding to claim 1 and claim 2). FIG. 1 is a configuration diagram illustrating an electric station operation support device according to a first embodiment. FIG.
In the figure, 22 is an inference method generating means for inferring the contents of the accident and the operation / failure of the device, and 23 is a judging means for using the inference method generated by the inference method generating means 22.

Next, the operation will be described. In FIG. 1, the inference method generation unit 22 analyzes the form of occurrence of the accident / failure from an enumeration example 211 of a combination example of the contents of the accident of the power system and the operation / failure of the power system protection / control device which are assumed in advance. The determination means 23 determines in advance the details of the failure of the power system and the operation and failure of the power system protection / control device from the input information 1 obtained at the time of the occurrence of the power system failure. -Outputs the failure result determination result 3. The analysis of the form of formation by the inference method generating means 22 will be described with reference to an enumeration case 211A in FIG. For example, a case set that can be established when the transmission line main protection relay 96 is assumed to be operating is ｛｝ of the content of the accident / failure, and a case set that can be established when the transmission line main protection relay 96 is assumed to be inoperative. Is the content of the accident / failure. From this, if the attribute value of the transmission line main protection relay 96 is determined, the case set that can be established can be limited to either ｛｝ or ｛｝,
Assuming that the transmission line main protection relay 96 is in operation and the case set ｛｝ is limited, the probability of occurrence of accident / failure content is 1/3, the probability of occurrence of accident / failure content is 1/3, and the accident / failure is The content occurrence probability is also 1/3.
Assuming that the transmission line main protection relay 96 is inactive and the case set 限定 is limited, the probability of occurrence of accident / failure content is 、 and the probability of occurrence of accident / failure content is also １ ／. In particular, when information on the occurrence probability of a case is obtained, the occurrence probability may be obtained based on the information. Similarly, a set of cases that can be established when the circuit breaker 92B is assumed to be OFF after an accident is ｛of the contents of the accident / failure.
事例, and a case set that can be established when the circuit breaker 92A is assumed to be ON after an accident is ｛｝ of the accident / failure content. Similarly, a set of cases that can be established when the circuit breaker 92A is assumed to be OFF after an accident is ｛of the contents of the accident / failure.
｝, And there is no case that can be established when the circuit breaker 92A is assumed to be ON after an accident. Hereinafter, similarly, regarding the transmission line back-up protection relay 97 and the bus protection relay 98,
A case set and an occurrence probability corresponding to the attribute value are obtained. Next, the entropy E ₁ meaning the degree of variation of all cases is calculated for each input item by the method of Expression 1.

(Equation 2) Here, the input items are A _i (i = 1, 2,..., L, where L is the number of input items), and the possible attribute values of the input item A _i are B _ij (j = 1, 2,. , M _i , M _i is the number of attribute values that A _i can have), and the accident / failure is classified into class C
_k (k = 1, 2,..., N, where N is the number of classes = the number of types of accidents / failures), and a set of cases that is satisfied when it is assumed that the attribute value of the input item A _i is B _ij ｛D _ijl ｝
(L = 1, 2,..., X _ij , where X _ij is the number of satisfied cases), and the probability of occurrence of class C _{k in} the case when the satisfied cases can be limited to elements of case set {D _ijl } To P _ijk
It is described. For example, focusing on the transmission line main protection relay 96 as an input item and limiting the set of established cases,
When entropy indicating the variation degree of all cases referred to as _{E 3, E 3 = E 31} + E 32 = 1.351 bit However,

(Equation 3) Similarly, when the set of established cases is limited by focusing on the circuit breaker 92A as an input item, the entropy indicating the degree of variation of all cases is E ₁ , and the set of established cases is limited by focusing on the circuit breaker 92B as an input item. The entropy indicating the degree of variation of all cases is E ₂ , the entropy indicating the degree of variation of all cases when the set of established cases is limited by focusing on the transmission line back-up protection relay 97 as an input item is E ₄ ,
When the set of established cases is limited by focusing on the bus protection relay 28 as an input item, the entropy indicating the degree of variation of all cases is calculated as E ₅ , and written together with E ₃ , E ₁ = 2.322 bits E ₂ = 1.944 bits E ₃ = 1.351 bits E ₄ = 1.6 bits E ₅ = 1.351 bits.

Here, an input item having the smallest value of entropy E _i is selected, and when an accident occurs in the power system, first, the case where the input item is satisfied is limited by focusing on this input item. In this example, the entropy _Ei has the smallest value when the transmission line main protection relay 96 is focused on as an input item and when the bus protection relay 98 is focused on as an input item. The transmission line main protection relay 96 is selected as an input item. Therefore, when an accident occurs in the power system, firstly, the established cases are limited to either the case set ｛｝ or the case set に よ り depending on the operation or non-operation of the transmission line main protection relay 96. Next, regarding the case set {or the case set} limited by the operation or non-operation of the transmission line main protection relay 96, assuming that the transmission line main protection relay 96 is excluded from the input items, the entropy E _i is the same as described above. Is calculated, and an input item having the smallest value is selected, and the selected input item is set as an input item to be referred to secondly in order to limit the content of the accident / failure when an accident occurs in the power system. The calculation of entropy for the case set 場合 when the transmission line main protection relay 96 is in operation will be described. For the case set ｛｝, entropy indicating the degree of variation of all cases when the case set is limited by focusing on the circuit breaker 92A as an input item is E ₁ , and the entropy is established by focusing on the circuit breaker 92B as an input item. The entropy indicating the degree of dispersion of all cases when the set of cases is limited is E ₂ , and the entropy indicating the degree of dispersion of all cases when the set of established cases is limited by focusing on the transmission line back-up protection relay 97 as an input item Is E ₄ , and entropy indicating the degree of variation of all cases when the set of established cases is limited by focusing on the bus protection relay 98 as an input item is E
₅ , E ₁ = 1.585 bits E ₂ = 1.189 bits E ₄ = 1.585 bits E ₅ = 0.667 bits, and the smallest entropy is obtained when attention is paid to the bus protection relay 98 as an input item. Therefore, when an accident occurs in the power system, first, the transmission line main protection relay 9
Focusing on No. 6, if this is an operation,
｝, In which case, second, the bus protection relay 9
Focusing on No. 8, the established cases are limited to either the case set ｛｝ or the case set に よ り depending on the operation or non-operation. At this time, if the bus protection relay 98 does not operate, it is determined that the content is an accident / failure. If the bus protection relay 98 operates, the established case is the case set ｛
｝, And entropy is calculated in the same manner as described above in order to further perform the third limitation. For the case set ｛｝, entropy indicating the degree of variation of all cases when the case set is limited by focusing on the circuit breaker 92A as an input item is E ₁ , and the entropy is established by focusing on the circuit breaker 92B as an input item. The entropy indicating the degree of dispersion of all cases when the set of cases is limited is E ₂ , and the entropy indicating the degree of dispersion of all cases when the set of established cases is limited by focusing on the transmission line back-up protection relay 97 as an input item Is calculated as E ₄ , E ₁ = 1 bit E ₂ = 1 bit E ₄ = 1 bit, and no further decrease in entropy is observed. This means that it is impossible to specify any more successful cases, and it is impossible to classify accidents / failures. This is obvious from the fact that the circuit breaker information and the relay operation information appear exactly the same in the accident / failure content of the case 211A shown in FIG. Therefore, when an accident occurs in the power system, first attention is paid to the transmission line main protection relay 96, and if this is an operation, the established case is the case set ｛
｝, And in this case, secondly, the bus protection relay 9
Focusing on No. 8, the established cases are limited to either the case set ｛｝ or the case set に よ り depending on the operation or non-operation. At this time, if the bus protection relay 98 does not operate, it is determined that the established case is an accident / failure content, and if the bus protection relay 98 is operating, the established case is the accident / failure content or the accident / failure content. And terminate the inference. At the time of the power system accident, first paying attention to the transmission line main protection relay 96, and when the attribute value thereof is inoperative, the same calculation as above is performed for the case set 、, and the determination method is determined. obtain. For the case set ｛｝, entropy indicating the degree of variation of all cases when the case set is limited by focusing on the circuit breaker 92A as an input item is E ₁ , and the entropy is established by focusing on the circuit breaker 92B as an input item. The entropy indicating the degree of dispersion of all cases when the set of cases is limited is E ₂ , and the entropy indicating the degree of dispersion of all cases when the set of established cases is limited by focusing on the transmission line back-up protection relay 97 as an input item Is E ₄ , and entropy indicating the degree of variation of all cases when the set of established cases is limited by focusing on the bus protection relay 98 as an input item is E
₅ , E ₁ = 1 bit E ₂ = 0.667 bit E ₄ = 0 bit E ₅ = 0 bit, and if the focus is on the transmission line back-up protection relay 97 or the bus protection relay 98 to limit the cases where it is established In this case, the established cases can be specified as one. Either the transmission line back-up protection relay 97 or the bus protection relay 98 may be used, but here, if the inference by the transmission line back-up protection relay 97 is adopted and the entire inference method is described, a tree structure shown in FIG. 2 is obtained. In FIG. 2, 41A, 41B and 41C are called "nodes" of the tree structure, and these are input items for limiting the enumerated examples. 42A, 42B, 42C, 42D,
42E and 42F are called "branches" of the tree structure, and these are attribute values of input items for limiting the enumerated examples. 43A, 43B, 43C and 43D are called "leaves" of a tree structure, and these are the contents of accidents and failures which are finally limited. The method represented by this tree structure is the inference method generated by the inference method generation means 22. The inference method generation means 22 analyzes the tree structure in advance, and when an accident occurs in the power system, the determination means 23 The content of the accident / failure is determined using the above tree structure.

On the other hand, in the first embodiment, when a specific input item is probabilistically significant when inferring the content of an accident or failure of an input item at the time of occurrence of an accident in the electric power system, the Sometimes, when an accident occurs due to an unexpected combination of input items that is not included in the enumerated examples, it is possible to infer unexpected accidents / failures by outputting a judgment result 3 having a high probability in frequency. is there.

Embodiment 2 FIG. Second Embodiment A second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a configuration diagram illustrating the electric station operation support device according to the second embodiment. In FIG. 3, reference numeral 4 denotes confirmation means for confirming that the input information 1 at the time of occurrence of the accident is assumed in the enumeration case 211.

Next, the operation of the second embodiment will be described.
By referring to the result confirmed by the confirmation unit 4 by the determination unit 23, when an accident of an unexpected input item not listed in the enumeration example 211 occurs, the accident / failure content that cannot be determined by the determination unit 23 is determined. The fact that occurrence has occurred is output as the determination result 3. As a result, according to the second embodiment, it is possible to easily recognize that an unexpected accident has occurred.

Embodiment 3 (corresponding to claim 3). Third Embodiment A third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a configuration diagram illustrating an electric station operation support device according to a third embodiment. In FIG. 4, reference numeral 4 denotes means for displaying the inference method generated by the inference method generation means 22 in a tree structure.

Next, the operation of the third embodiment will be described.
Means 4 for displaying the inference method generated by the inference method generation means 22 in a tree structure is used. FIG. 2 shows an example of the display of the tree structure. Therefore, according to the third embodiment, the operator can easily understand the accident / failure determination process.

Embodiment 4 FIG. Embodiment 4 of the present invention will be described with reference to FIG. FIG. 5 is a configuration diagram illustrating an electric station operation support device according to a fourth embodiment. In FIG. 5, reference numeral 6 denotes a computer program for realizing the inference method generated by the inference method generation means 22.

Next, the operation of the fourth embodiment will be described.
By incorporating the computer program 6 into the judgment means 23, it is possible to easily realize the logic of the method of inferring the details of the accident / failure.

Embodiment 5 FIG. Embodiment 5 of the present invention will be described with reference to FIG. FIG. 6 is a configuration diagram illustrating an electric station operation support device according to a fifth embodiment. In FIG. 6, reference numeral 7 denotes a unit for converting the determination rule of the inference method generated by the inference method generation unit 22 into a code form that can be processed by a computer.

Next, the operation of the fifth embodiment will be described.
By incorporating the code morphing means 7 into the judging means 23, it is possible to easily realize the development of the rules of the method of inferring the contents of accidents and failures and the judging function by a computer using expert knowledge.

Embodiment 6 FIG. A sixth embodiment of the present invention will be described with reference to FIG. FIG. 7 is a configuration diagram illustrating an electric station operation support device according to a sixth embodiment. In FIG. 7, 8 is an enumeration case 21
1 is a changing means for changing the number 1.

Next, the operation of the sixth embodiment will be described.
If the change means 8 changes the accident / failure content of the enumeration case 211 and the state of the relay and the protection relay, the inference method generation means 22 analyzes with the changed enumeration case 211 and the judgment means 23 outputs the power system accident content. Then, the operation / failure of the power system protection / control device is determined and the result 3 of the accident / failure determination is output. Therefore, according to the sixth embodiment, it is easy to change the inference, and the range of support of the power system and the power system protection / control device is widened.

[0031]

As described above, according to the first aspect of the present invention, the form of verification of the expert knowledge of the code form, which can occur when an accident occurs in the power system, is analyzed in advance, and the input information at the time of the accident and It is configured to automatically generate a method for inferring the content of accidents / failures in the input items at the time of an accident because the number of comparison judgments is smaller than the case of comparing and matching the enumerated cases as it is. It is possible to determine the details of the accident and the operation / failure of the device at a higher speed than when the expert knowledge of the form is directly collated.

According to the second aspect of the present invention, by limiting the cases where the entropy is stopped until the decrease of the entropy stops, a method for inferring the content of the accident / failure of the input item at the time of the accident is automatically generated. When an accident occurs in the power system, there is an effect that the accident contents and the operation / failure contents of the device can be determined at high speed.

According to the third aspect of the present invention, since the method of inferring the contents of an accident / failure of an input item at the time of occurrence of an accident is expressed using a tree structure, the contents of the accident and the operation / failure of the apparatus are determined. There is an effect that the process of performing can be easily understood visually.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an electric station operation support device according to a first embodiment.

FIG. 2 is a diagram illustrating an inference tree structure according to the first and second embodiments.

FIG. 3 is a configuration diagram illustrating an electric station operation support device according to a second embodiment.

FIG. 4 is a configuration diagram illustrating an electric station operation support device according to a third embodiment.

FIG. 5 is a configuration diagram illustrating an electric station operation support device according to a fourth embodiment.

FIG. 6 is a configuration diagram illustrating an electric station operation support device according to a fifth embodiment.

FIG. 7 is a configuration diagram illustrating an electric station operation support device according to a sixth embodiment.

FIG. 8 is a configuration diagram showing a conventional electric station operation support device.

FIG. 9 is a system diagram showing a power system protection / control device.

FIG. 10 is a diagram showing an example of enumeration of a combination example of the details of an accident in the power system and the details of operation and failure of the power system protection / control device.

[Explanation of symbols]

1 Input information at the time of accident occurrence, 2 Electric station operation support device,
3 Judgment result, 5 tree structure display means, 10 protection range of transmission line main protection relay, 11 protection range of bus protection relay, 12A to 12D accident location, 22 inference method generation means, 23 judgment means, 96 transmission line main protection relay , 9
7 Transmission line back protection relay, 98 bus protection relay.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-310319 (JP, A) JP-A-59-188317 (JP, A) JP-A-1-104144 (JP, A) JP-A-2- 168827 (JP, A) JP-A-1-147602 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02J 13/00-13/00 311

Claims (3)

(57) [Claims] The present invention includes an example of enumeration of accidents and failures which is assumed in advance as a code form that enables a computer to process expert knowledge on a power system and a power system protection / control device. And the like, and the operation information of the power system protection / control device such as the operation information of the protection relay of the power system as input information.When the power system accident occurs, the input information is converted into expert knowledge of the code form. The power station accident assist system that applies the artificial intelligence AI to collate and judge the contents of the accident of the electric power system and the operation / failure of the electric power system protection / control device, and outputs the judgment result. The form of verification of the code form to the expert knowledge is analyzed in advance, and the analyzed form of verification is used to determine the content of the accident / failure at the time of the power system accident. An electric station operation support device comprising an inference method generating means used for determination. 2. As an inference method for analyzing the above-mentioned matching establishment form in advance, the input items are A _i (i = 1, 2,..., L, L is the number of input items), and the input items A _i The attribute values to be obtained are represented by B _ij (j = 1, 2 _,.
.., M _i , where M _i is the number of attribute values that A _i can take), and classify the accident / failure class C _k (k = 1, 2,..., N)
Where N is the number of classes = the number of types of accidents / failures), and the case set that holds when the attribute value of the input item A _i is B _ij is {D _ijl } (l = 1, 2, ...
X _ij , where X _ij is the number of established cases), and when the established cases can be limited to the elements of the case set {D _ijl }, the occurrence probability of class C _{k in} the case is described as P _ijk . An established case set {D _ijl } is obtained for each attribute value B _{ij that the} item A _i can take, and the entropy E _i that means the degree of variation of all cases is calculated for each A _i (i =
1, 2, · · ·, L) calculated to obtain the smallest input fields A _i of E _i, a i at this time and tl, the possible attribute values B _T1j established cases for each of the input fields A _t1 Set {D _t1jl } (l = 1,2, ...
-, obtained in advance X _T1j), then the input fields established case set for each attribute value B _T1j which may take the _{A t1} {D t1jl}, respectively, treated as the listed cases, input fields, excluding the A _t1 From the input item A having the smallest entropy in the same manner as the above-mentioned A _t1 was obtained.
and _t2, the input fields established case set for each attribute value B _T2j which may take the _{A t2 {D t2jl} (l} = 1,2, ···, X t2j) obtained in advance, and the same in case classification repeating, first, limiting the accident or fault condition by the attribute values of the input items a _t1, then the accident or malfunction contents defined by the attribute values of the input items a _t1, attributes of the input fields a _t2 Based on the value, the details of the accident / failure can be further limited. In the following, it is possible to limit the details of the accident / failure to one. The method for inferring the details of an accident or a failure used in an electric station operation support device according to claim 1, wherein the contents are classified so as to infer the details of the accident or a failure from input items when an accident occurs in the power system. (Equation 1) 3. The substation operation support according to claim 1, further comprising means for expressing a collation form of the inferred accident / failure contents of the input item at the time of the occurrence of the accident using a tree structure. apparatus.