Power system shutdown planning support device, computer program for the same, and power system shutdown planning support method

Abstract

To provide a power system shutdown planning support device that satisfies the constraints for stopping the power supply and supports to select more quickly than before a section where power supply is to be stopped in a power system.SOLUTION: A power system shutdown planning support device 1 has: a graph conversion unit 101 that creates a power system graph by converting the configuration of a power system that supplies power into a geometric model consisting of nodes and branches connecting the nodes; a partial graph enumeration unit 102 that creates one or more shutdown candidate power system graphs, which are geometric models of the power system in which the branch that stops the power supply is selected on the basis of the power system graph created by the graph conversion unit 101; and a shutdown candidate system configuration evaluation unit 103 that evaluates a shutdown candidate power system graph created by the partial graph enumeration unit 102 on the basis of pre-set constraint information D04 that indicates the constraint conditions of the power system whose power supply is to be stopped.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present embodiment relates to a power system shutdown plan creation support device, a computer program for the power system shutdown plan creation support device, and a power system shutdown plan creation support method that support the selection of a section of a power system to which power supply is to be stopped when creating a plan to stop the supply of power. [Background technology]

[0002] In order to maintain a stable supply of power, maintenance work is performed on a power system. In some cases, the power supply in a section of the power system is stopped during the maintenance work. A power system shutdown plan creation support device that supports the creation of a plan to stop the supply of power is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-32440 A Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, in maintenance work for maintaining a stable supply of power, the supply of power to a part of a section of a power system may be stopped. Even when the supply of power to a part of a section is stopped, it is preferable to maintain a predetermined supply of power to loads in the entire power system.

[0005] There was a problem in that it was complicated to create a power system shutdown plan that ensured the reliability of locations where the power supply would not be shut down, while at the same time shutting down the power supply to locations where the power supply would be shut down, and maintained a specified power supply to loads throughout the entire power system.

[0006] In consideration of the above problems, the present embodiment aims to provide a power system shutdown plan creation support device, a computer program for the power system shutdown plan creation support device, and a power system shutdown plan creation support method that support more quickly selecting a section in a power system to which power supply is to be stopped, which satisfies constraints for stopping the power supply. [Means for solving the problem]

[0007] The power system shutdown plan creation support device of this embodiment has the following features. (1) A graph conversion unit converts the configuration of a power system that supplies power into a geometric model consisting of nodes and branches connecting the nodes, and creates a power system graph. (2) A subgraph enumeration unit that creates one or more shutdown candidate power system graphs, which are geometric models of a power system that select branches to shut down the power supply, based on the power system graph created by the graph conversion unit. (3) A shutdown candidate system configuration evaluation unit is provided that evaluates the shutdown candidate power system graph created by the subgraph enumeration unit based on preset constraint information indicating constraint conditions of the power system regarding the shutdown of power supply. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a configuration of a power system shutdown plan creation support device 1 according to a first embodiment. [Diagram 2] FIG. 1 is a diagram showing a program flow of a power system shutdown plan creation support device 1 according to a first embodiment. [Diagram 3] FIG. 1 is a diagram showing an example of system configuration information D01 of a power system shutdown plan creation support device 1 according to a first embodiment. [Figure 4] FIG. 1 is a diagram showing an example of graph information D02 of a power system shutdown plan creation support device 1 according to a first embodiment. [Diagram 5] FIG. 1 is a diagram showing an example of shutdown candidate system configuration information D03 of the power system shutdown plan creation support device 1 according to the first embodiment. [Figure 6]FIG. 1 is a diagram showing an example of constraint information D04 of a power system shutdown plan creation support device 1 according to a first embodiment. [Figure 7] FIG. 1 is a diagram showing an example of system evaluation information D05 related to the evaluation based on the remaining cost value of the power system shutdown plan creation support device 1 according to the first embodiment. [Figure 8] FIG. 1 is a diagram showing an example of system evaluation information D05 related to evaluation based on failure probability by the power system shutdown plan creation support device 1 according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [First embodiment] [1-1. Configuration] As an example of the present embodiment, the configuration of a power system shutdown plan creation support device 1 will be described with reference to Fig. 1. The power system shutdown plan creation support device 1 is configured with a computer. The power system shutdown plan creation support device 1 satisfies constraints for stopping the power supply and provides support for more quickly selecting a section in the power system where the power supply is to be stopped.

[0010] The power system shutdown plan creation support device 1 includes a processing unit 10, a storage unit 20, an input unit 40, and an output unit 50.

[0011] The processing unit 10 is configured by a central processing unit (CPU) of a computer, etc. The processing unit 10 has a graph conversion unit 101, a subgraph enumeration unit 102, and a candidate system configuration evaluation unit 103. The graph conversion unit 101, the subgraph enumeration unit 102, and the candidate system configuration evaluation unit 103 are configured by software modules or hardware.

[0012] The processing unit 10 is connected to the storage unit 20, the input unit 40, and the output unit 50. The processing unit 10 controls the storage unit 20, the input unit 40, and the output unit 50.

[0013] The storage unit 20 is configured with a storage medium such as a hard disk or a semiconductor memory. The storage unit 20 is connected to the processing unit 10. The processing unit 10 controls the writing and reading of data to and from the storage unit 20.

[0014] The memory unit 20 has a system configuration database 201 (hereinafter referred to as "system configuration DB201"), a graph database 202 (hereinafter referred to as "graph DB202"), a stop candidate system configuration database 203 (hereinafter referred to as "stop candidate system configuration DB203"), a constraint database 204 (hereinafter referred to as "constraint DB204"), and a system evaluation database 205 (hereinafter referred to as "system evaluation DB205").

[0015] The system configuration DB 201 of the storage unit 20 stores system configuration information D01. The graph DB 202 stores graph information D02. The candidate system configuration DB 203 stores candidate system configuration information D03. The constraint DB 204 stores constraint information D04. The system evaluation DB 205 stores system evaluation information D05.

[0016] The graph conversion unit 101 of the processing unit 10 creates graph information D02 based on system configuration information D01. The system configuration information D01 is stored in the system configuration DB 201. The system configuration information D01 is information about the configuration of the target electric power system. The system configuration information D01 includes information about the overall configuration of the electric power system made up of each node and each branch. An example of the system configuration information D01 is shown in FIG. 3.

[0017] The graph conversion unit 101 extracts a target power system from the system configuration information D01, creates a geometric model of the power system, and sets it as graph information D02. The graph information D02 is information that represents the core configuration of the power system as a geometric model consisting of nodes and branches. The graph information D02 is stored in the graph DB 202. An example of the graph information D02 is shown in FIG. 4.

[0018] The subgraph enumeration unit 102 of the processing unit 10 creates candidate system configuration information D03 to be shut down based on the graph information D02 created by the graph conversion unit 101.

[0019] The shutdown candidate power system configuration information D03 is information configured by one or more shutdown candidate power system graphs. The shutdown candidate power system graph is information that expresses the configuration of the power system including the branch to be shut down by a geometric model. The shutdown candidate power system graph is a candidate for the configuration of the power system including the branch to be shut down.

[0020] The subgraph enumeration unit 102 creates a candidate power system graph for suspension based on a geometric configuration including the entire range of nodes and branches related to the graph information D02 created by the graph conversion unit 101. The candidate power system graph for suspension indicates a geometric configuration of a power system including branches for which power supply is to be suspended. In one candidate power system graph for suspension, the branch for which power supply is to be suspended may be one or multiple.

[0021] The subgraph enumeration unit 102 sets the created one or more candidate power system graphs for shutdown as candidate system configuration information for shutdown D03. The candidate system configuration information for shutdown D03 is stored in the candidate system configuration for shutdown DB 203. Fig. 5 shows an example of the candidate system configuration information for shutdown D03.

[0022] The candidate system configuration for shutdown evaluation unit 103 of the processing unit 10 creates system evaluation information D05 based on the candidate system configuration for shutdown information D03 created by the subgraph enumeration unit 102.

[0023] The stop candidate system configuration evaluation unit 103 evaluates the stop candidate power system graph according to the stop candidate system configuration information D03 created by the subgraph enumeration unit 102. The stop candidate system configuration evaluation unit 103 receives the constraint information D04 and evaluates the stop candidate power system graph based on the constraint information D04.

[0024] The constraint information D04 includes information on the constraint conditions. The constraint conditions set in the constraint information D04 are information on the evaluation of the branch that stops the power supply. The constraint information D04 is set and stored in advance in the constraint DB 204 via the input unit 40. An example of the constraint information D04 is shown in FIG. 6.

[0025] The candidate system configuration for suspension evaluation unit 103 performs evaluation for each candidate power system graph for suspension based on the constraint conditions set in the constraint information D04.

[0026] The stop candidate system configuration evaluation unit 103 evaluates the stop candidate power system graph and creates system evaluation information D05. The system evaluation information D05 is information on the evaluation of the power system when the power supply of the branch related to the stop candidate power system graph is stopped. The system evaluation information D05 is stored in the system evaluation DB 205. An example of the system evaluation information D05 is shown in Fig. 7 and Fig. 8.

[0027] The system configuration DB 201 of the storage unit 20 accumulates and stores system configuration information D01. As shown in Fig. 3, the system configuration information D01 is information related to the configuration of a target power system. The system configuration information D01 is set and stored in advance in the system configuration DB 201 via the input unit 40. The system configuration information D01 includes information related to the geometric configuration of the power system.

[0028] The system configuration information D01 may include information on the lower and upper limits of voltage for each node in the power system. The system configuration information D01 may include information on the impedance and capacitance for each branch.

[0029] The graph DB 202 of the storage unit 20 accumulates and stores the graph information D02. As shown in Fig. 4, the graph information D02 is information that represents the core configuration of the power system by a geometric model consisting of nodes and branches. The graph information D02 is created by the graph conversion unit 101 of the processing unit 10.

[0030] The shutdown candidate system configuration DB203 of the storage unit 20 accumulates and stores shutdown candidate system configuration information D03. As shown in FIG. 5, the shutdown candidate system configuration information D03 is information configured of one or more shutdown candidate power system graphs. The shutdown candidate power system graph is information that represents, in a geometric model, the configuration of a power system including a branch for stopping power supply. The shutdown candidate power system graph is a candidate for the configuration of a power system including a branch for stopping power supply. The shutdown candidate system configuration information D03 is created by the subgraph enumeration unit 102 of the processing unit 10.

[0031] The constraint DB 204 of the storage unit 20 accumulates and stores the constraint information D04. The constraint information D04 includes information on constraint conditions. The constraint conditions are information on the evaluation of the branch that stops the power supply. The constraint information D04 is set in advance in the constraint DB 204 via the input unit 40 and stored therein.

[0032] As shown in FIG. 6, the constraint information D04 includes a cost case database (hereinafter referred to as a cost case DB) and an equipment database with case classification (hereinafter referred to as an equipment DB with case classification) as constraint conditions.

[0033] The cost case DB includes, for each case ID for stopping the power supply, details regarding the power supply stop, a "remaining cost value" indicating the degree of risk of using the power supply route, and an "individual failure probability."

[0034] The degree of risk of using a power supply route increases as the interruption of the power supply becomes undesirable.

[0035] As an example, the degree of risk of using a supply route in accordance with the constraint conditions set in the constraint information D04 is the "remaining cost value." As shown in the cost case DB in FIG. 6, the "remaining cost value" is set for each "content" indicating the equipment related to the power supply stop corresponding to the case ID. The equipment DB with case classification in FIG. 6 indicates the branch ID corresponding to the case ID. By using the cost case DB of the constraint information D04 and the equipment DB with case classification together, it is possible to detect the "remaining cost value" for each branch. The "remaining cost value" is an index of the cost for each of the other branches that do not stop the power supply when the power supply of a specified branch is stopped.

[0036] As an example, the "individual failure probability" related to the constraint condition set in the constraint information D04 is numerical information related to the probability of failure occurring for each branch that is allowed to remain without stopping the power supply.

[0037] The constraint information D04 may include constraints on the installation positions of branches, constraints based on rules or conventions that are artificial arrangements, and constraints on the phase or voltage of each node in the power system. For this reason, the above constraints may be called "preference constraints" in the sense that they also include numerical values ​​that do not necessarily have a physical or electrical background.

[0038] The constraint information D04 may also include information on "power lines that must be selected simultaneously." The "power lines that must be selected simultaneously" is information on other branches to which it is preferable to stop the power supply when one branch to stop the power supply is selected. The constraint DB 204 may include other constraint conditions.

[0039] The system evaluation DB205 of the storage unit 20 accumulates and stores system evaluation information D05. The system evaluation information D05 is information on the evaluation of the power system graph of the candidate to be stopped, which has caused the power supply of the branch to be stopped. The system evaluation information D05 is created by the candidate to be stopped system configuration evaluation unit 103 of the processing unit 10. Two pieces of system evaluation information D05, namely, system evaluation information D05 related to the evaluation based on the remaining cost value shown in Fig. 7 and system evaluation information D05 related to the evaluation based on the failure probability shown in Fig. 8, are stored in the system evaluation DB205 as system evaluation information D05.

[0040] The input unit 40 is composed of an operating device such as a keyboard, a mouse, a touch panel, or a receiving circuit, or an external memory connection circuit. The input unit 40 is connected to the processing unit 10. It is operated by an operator, and information to be stored in the storage unit 20 is input from the input unit 40. Information to be stored in the storage unit 20 may be input via the input unit 40 from communication or an external storage device. The information or data input from the input unit 40 is stored in the storage unit 20.

[0041] The output unit 50 is composed of a display device such as a liquid crystal display, a printing device such as a printer, a transmission circuit, an external memory connection circuit, etc. The output unit 50 is connected to the processing unit 10. The output unit 50 outputs system evaluation information D05 created by the processing unit 10. The output unit 50 may be configured to output the shutdown candidate system configuration information D03 and the graph information D02. The output unit 50 outputs the system evaluation information D05, the shutdown candidate system configuration information D03, or the graph information D02 by display, printout, or electronic data.

[0042] The output unit 50 transmits the system evaluation information D05, the shutdown candidate system configuration information D03, or the graph information D02 to an external device. The external device connected to the output unit 50 may be an I / O device such as a printer or a monitor, an external storage device, or an external control device or computer device.

[0043] The above is the configuration of the power system shutdown plan creation support device 1 according to this embodiment.

[0044] [1-2. Effect]

[0045] Next, the operation of the power system shutdown plan creation support device 1 of this embodiment will be described with reference to FIGS.

[0046] The power system shutdown plan creation support device 1 supports quicker selection of a section in the power system where the power supply is to be stopped, which satisfies the constraint conditions for stopping the power supply.

[0047] The graph conversion unit 101 of the power system shutdown plan creation support device 1 converts the configuration of the power system that supplies power into a geometric model consisting of nodes and branches that connect the nodes, and creates a power system graph.

[0048] The subgraph enumeration unit 102 of the power system shutdown plan creation support device 1 creates one or more shutdown candidate power system graphs, which are geometric models of the power system that select branches for shutting down the power supply, based on the power system graph created by the graph conversion unit 101. General-purpose techniques for enumerating subgraphs such as spanning trees from a graph structure have been put to practical use, and in recent years, a high-speed method that utilizes a special data structure called ZDD (Zero-suppressed binary Decision Diagram) has become known. ZDD is described in detail in the following non-patent document, for example: "Jun Kawahara, Shinichi Minato, Application of Graph Enumeration and Indexing Techniques to Various Problems, Operations Research, Vol. 57, No. 11, 2012"

[0049] The power system shutdown candidate system configuration evaluation unit 103 of the power system shutdown plan creation support device 1 evaluates the shutdown candidate power system graph created by the subgraph enumeration unit 102 based on preset constraint information D04 indicating constraint conditions of the power system regarding the shutdown of power supply.

[0050] The constraint conditions set in the constraint information D04 include the degree of risk of using each branch that constitutes the power system as a supply route, and the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate power system graph created by the subgraph enumeration unit 102 based on the degree of risk of using it as a supply route.

[0051] The constraint conditions set in the constraint information D04 include numerical information on the probability of a fault occurring for each branch that constitutes the power system, and the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate power system graph created by the subgraph enumeration unit 102 based on the numerical information on the probability of a fault occurring.

[0052] The constraint conditions set in the constraint information D04 may include at least one of constraints on the installation position of the branch, constraints based on rules or conventions that are artificial agreements, and constraints on the phase or voltage of each node in the power system.

[0053] The subgraph enumeration unit 102 creates one or more shutdown candidate power system graphs.

[0054] The operation of the power system shutdown plan creation support device 1 is as follows.

[0055] The system configuration DB201 of the storage unit 20 accumulates and stores system configuration information D01. The system configuration information D01 is information about the configuration of the target power system. The system configuration information D01 is set and stored in advance in the system configuration DB201 via the input unit 40. The system configuration information D01 is information about the geometric configuration of the power system as shown in FIG. 3. The system configuration information D01 may include information about the lower and upper voltage limits of each node in the power system. The system configuration information D01 may include information about the impedance and capacitance of each branch.

[0056] The graph conversion unit 101 of the processing unit 10 receives the system configuration information D01 from the system configuration DB 201 of the storage unit 20. The graph conversion unit 101 creates graph information D02 based on the system configuration information D01.

[0057] The graph information D02 is information that represents the core configuration of the power system as a geometric model consisting of nodes and branches. The graph conversion unit 101 extracts the target part of the power system from the system configuration information D01, creates a geometric model of the part of the power system, and sets it as the graph information D02.

[0058] The graph conversion unit 101 converts the power system according to the system configuration information D01 into an undirected graph, assuming that the power system is an electric circuit model in which nodes are connected by branches.

[0059] Graph information D02 indicates a geometric configuration of nodes and branches as shown in Fig. 4. A branch corresponds to a portion of a power system that is configured by power transmission lines or power transmission and transformation equipment such as transformers. Graph conversion unit 101 stores graph information D02 in graph DB 202 of storage unit 20.

[0060] The subgraph enumeration unit 102 of the processing unit 10 creates shutdown candidate system configuration information D03 based on the graph information D02 created by the graph conversion unit 101. The shutdown candidate system configuration information D03 is information configured of one or more shutdown candidate power system graphs. The shutdown candidate power system graph is information that represents the configuration of a power system including a branch for stopping power supply, using a geometric model. In one shutdown candidate power system graph, the branch for stopping power supply may be one or more. Each shutdown candidate power system graph is a candidate for the configuration of a power system including a branch for stopping power supply.

[0061] As an example, the subgraph enumeration unit 102 reduces the graph structure related to the power system configuration converted into an undirected graph by the graph conversion unit 101 to intermediate data called a zero-suppressed binary decision diagram (ZDD). The subgraph enumeration unit 102 uses the ZDD to enumerate a predetermined number of solution candidates, which are set as the shutdown candidate system configuration information D03. In this embodiment, the power system configuration candidates related to the shutdown candidate system configuration information D03 are enumerated as spanning trees. The enumeration of the spanning trees may be realized by repeatedly applying an algorithm such as Prim instead of the ZDD.

[0062] A spanning tree means a "tree that includes all vertices," and in this embodiment corresponds to a geometric model that includes all nodes of the target power system and has no loops.

[0063] The subgraph enumeration unit 102 creates a candidate power system graph for suspension based on a geometric configuration including the entire range of nodes and branches related to the graph information D02 created by the graph conversion unit 101. The candidate power system graph for suspension indicates a geometric configuration of a power system including branches for which power supply is to be suspended. In one candidate power system graph for suspension, the branch for which power supply is to be suspended may be one or multiple.

[0064] The subgraph enumeration unit 102 sets the created one or more candidate power system graphs for shutdown as candidate system configuration information for shutdown D03 shown in Fig. 5. The subgraph enumeration unit 102 stores the created candidate system configuration information for shutdown D03 in the candidate system configuration for shutdown DB 203 of the storage unit 20.

[0065] The candidate system configuration for shutdown evaluation unit 103 of the processing unit 10 creates system evaluation information D05 based on the candidate system configuration for shutdown information D03 created by the subgraph enumeration unit 102.

[0066] The shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate power system graph according to the shutdown candidate system configuration information D03 created by the subgraph enumeration unit 102. The shutdown candidate system configuration evaluation unit 103 receives the constraint information D04, and evaluates the shutdown candidate power system graph included in the shutdown candidate system configuration information D03 based on the constraint information D04.

[0067] The constraint information D04 is stored in the constraint DB 204. The constraint information D04 includes information on constraint conditions. The constraint conditions are information on the evaluation of the branch that stops the power supply. The constraint information D04 is set and stored in advance in the constraint DB 204 via the input unit 40.

[0068] As shown in FIG. 6, the constraint information D04 includes a cost case DB and a facility DB with case classification as constraint conditions.

[0069] The cost case DB includes, for each case ID for stopping the power supply, details regarding the power supply stop, a "remaining cost value" indicating the degree of risk of using the power supply route, and an "individual failure probability."

[0070] The degree of risk of using a power supply route increases as the interruption of the power supply becomes undesirable.

[0071] As an example, the degree of risk of using a given branch as a power supply route, which is related to the constraint conditions set in the constraint information D04, is the “remaining cost value.” The “remaining cost value” is an index of the cost of each of the other branches whose power supply is not stopped, in the case where the power supply of a given branch is stopped.

[0072] As an example, the "individual failure probability" related to the constraint condition set in the constraint information D04 is numerical information related to the probability of failure occurring for each branch that is allowed to remain without stopping the power supply.

[0073] The equipment DB with case classification includes information on the name of each branch ID and the related case ID. The equipment DB with case classification is used when searching for a case ID in the branch and cost case DB.

[0074] For example, when stopping the power supply of branch A, the corresponding case ID is "C3." It can be found from the cost case DB that the degree of risk for using the power supply route corresponding to case ID "C3" is "10," and the individual failure probability is "0.1."

[0075] The stop candidate system configuration evaluation unit 103 evaluates each candidate in the stop candidate power system graph included in the stop candidate system configuration information D03 created by the subgraph enumeration unit 102 when power supply to each branch in the stop candidate power system graph is stopped. The system evaluation information D05 is information on the evaluation of each stop candidate power system graph when power supply to each branch is stopped. The stop candidate system configuration evaluation unit 103 creates system evaluation information D05 for each stop candidate power system graph included in the stop candidate system configuration information D03.

[0076] The shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate power system graph based on the "remaining cost value" of each branch to be shut down, which is included in the constraint information D04. The "remaining cost value" is one of the constraint conditions set in the constraint information D04. The shutdown candidate system configuration evaluation unit 103 creates system evaluation information D05 related to the evaluation based on the remaining cost value. The system evaluation information D05 related to the evaluation based on the remaining cost value is created as shown in FIG. 7.

[0077] In Figure 7, [Candidate 1] shows the case where the power supply to branch D is stopped. In [Candidate 1], the "remaining cost value" of branch A, which was allowed to remain without stopping its power supply, is "10", the "remaining cost value" of branch B is "10", and the "remaining cost value" of branch C is "3". The evaluation value of [Candidate 1] is calculated as the sum of the "remaining cost values" of the branches that were allowed to remain without stopping their power supply, resulting in "23".

[0078] Similarly, the evaluation value of [Candidate 2], which is the case when the power supply to branch C is stopped, is "21." Moreover, the evaluation value of [Candidate 3], which is the case when the power supply to branch B is stopped, is "14."

[0079] In the system evaluation information D05 relating to the evaluation based on the remaining cost value, a low evaluation value means a low cost burden. The suspension candidate system configuration evaluation unit 103 determines that [Candidate 3], which has a low evaluation value, is a good power system configuration when the power supply to the branch is suspended.

[0080] The stop candidate system configuration evaluation unit 103 evaluates the stop candidate power system graph based on the "individual failure probability" of each branch for which power supply is to be stopped, which is included in the constraint information D04. The "individual failure probability" is one of the constraint conditions set in the constraint information D04. The stop candidate system configuration evaluation unit 103 creates system evaluation information D05 related to the evaluation based on the failure probability. The system evaluation information D05 related to the evaluation based on the failure probability is created as shown in FIG. 8.

[0081] In Figure 8, [Candidate 1] shows the case where the power supply to branch D is stopped. In [Candidate 1], the "individual failure probability" of branch A, which was allowed to remain without stopping the power supply, is "0.1", the "individual failure probability" of branch B is "0.01", and the "individual failure probability" of branch C is "0.0025". The evaluation value of [Candidate 1] is calculated based on the "individual failure probability" of the branches that were allowed to remain without stopping the power supply, and is "0.1312".

[0082] The evaluation value for the failure probability evaluation of [Candidate 1] is calculated using (Equation 1). 1-(1-0.025)(1-0.01)(1-0.1)=0.131275 ...(Formula 1)

[0083] The evaluation value of [Candidate 2], which is the case when the power supply to branch C is stopped, is "0.12682." The evaluation value for the evaluation based on the failure probability of [Candidate 2] is calculated using (Equation 2). 1-(1-0.02)(1-0.01)(1-0.1)=0.12682 ...(Formula 2)

[0084] The evaluation value of [Candidate 3], which is the case when the power supply to branch B is stopped, is "0.14005." The evaluation value for the evaluation of [Candidate 3] based on the failure probability is calculated using (Equation 3). 1-(1-0.02)(1-0.025)(1-0.1)=0.14005 ...(Formula 3)

[0085] In the system evaluation information D05 relating to the evaluation based on the failure probability, a low evaluation value means that the probability of failure occurring in the entire power system is low. The suspension candidate system configuration evaluation unit 103 judges that [Candidate 2], which has a low evaluation value, is good as the configuration of the power system when the power supply of the branch is suspended.

[0086] The shutdown candidate system configuration evaluation unit 103 may perform evaluation for each shutdown candidate power system graph based on the constraints on the installation positions of the branches, the constraints based on rules or conventions which are artificial arrangements, and the constraints on the phase or voltage of each node in the power system, which are included in the constraint information D04, and create system evaluation information D05.

[0087] The suspension candidate system configuration evaluation unit 103 may calculate the phase or voltage of each node in the power system by power flow calculation, and perform evaluation based on constraints on the phase or voltage of each node.

[0088] The stop candidate system configuration evaluation unit 103 may evaluate the stop candidate power system graph based on information related to the "power lines that must be selected simultaneously". The constraint information D04 may include information related to the "power lines that must be selected simultaneously". The "power lines that must be selected simultaneously" is information related to other branches for which it is preferable to stop the power supply along with one branch that is selected to stop the power supply. The stop candidate system configuration evaluation unit 103 may evaluate each stop candidate power system graph based on information related to other branches for which it is preferable to stop the power supply, and create system evaluation information D05.

[0089] The candidate system configuration evaluation unit for shutdown 103 stores the system evaluation information D05 in the system evaluation DB 205 of the storage unit 20.

[0090] The output unit 50 outputs the system evaluation information D05 created by the processing unit 10. The output unit 50 may output the candidate system configuration information D03 to be stopped and the graph information D02. The output unit 50 outputs the system evaluation information D05, the candidate system configuration information D03 to be stopped, or the graph information D02 in the form of display, printout, or electronic data.

[0091] The output unit 50 transmits the system evaluation information D05, the shutdown candidate system configuration information D03, or the graph information D02 to an external device. The external device connected to the output unit 50 may be an I / O device such as a printer or a monitor, an external storage device, or an external control device or computer device.

[0092] The worker refers to the system evaluation information D05 output from the power system shutdown plan creation support device 1, and selects a branch related to a power system that satisfies predetermined conditions as a branch for actually shutting down the power supply in each procedure of the maintenance work.

[0093] The above-mentioned operation of the power system shutdown plan creation support device 1 is realized by a program shown in Fig. 2. The program shown in Fig. 2 is stored in the processing unit 10 of the power system shutdown plan creation support device 1.

[0094] (Step S01: Receive system configuration information D01) The processing unit 10 receives system configuration information D01 from the system configuration DB 201 of the storage unit 20. The operation of step S01 is executed by the graph conversion unit 101 of the processing unit 10. The system configuration information D01 is set and stored in advance in the system configuration DB 201 via the input unit 40. The system configuration information D01 is information related to the geometric configuration of the power system.

[0095] (Step S02: Create graph information D02) The processing unit 10 creates graph information D02 based on the system configuration information D01 received in step S01. The operation in step S02 is executed by the graph conversion unit 101 of the processing unit 10. The graph conversion unit 101 extracts the target part of the power system from the system configuration information D01, and creates a geometric configuration of the part of the power system as graph information D02. The graph information D02 is information that represents the core configuration of the power system as a geometric model consisting of nodes and branches.

[0096] (Step S03: Store the graph information D02) The processing unit 10 stores the graph information D02 created in step S02 in the graph DB 202 of the storage unit 20. The operation of step S03 is executed by the graph conversion unit 101 of the processing unit 10. The graph DB 202 of the storage unit 20 accumulates and stores the graph information D02 created by the processing unit 10.

[0097] (Step S04: Create shutdown candidate system configuration information D03) The processing unit 10 generates shutdown candidate system configuration information D03 based on the graph information D02 generated in step S02. The operation in step S04 is executed by the subgraph enumeration unit 102 of the processing unit 10.

[0098] The candidate system configuration information D03 for suspension is information that graphically represents candidates for the configuration of the power system to which power supply is to be suspended.

[0099] The subgraph enumeration unit 102 creates a candidate power system graph for shutdown based on a geometric configuration including the entire area of ​​nodes and branches related to the graph information D02. The candidate power system graph for shutdown indicates a geometric configuration of a power system including branches for which power supply is to be stopped. In one candidate power system graph for shutdown, the branch for which power supply is to be stopped may be one or more. The subgraph enumeration unit 102 sets the created one or more candidate power system graphs for shutdown as candidate system configuration information for shutdown D03.

[0100] (Step S05: Store the shutdown candidate system configuration information D03) The processing unit 10 stores the shutdown candidate system configuration information D03 created in step S04 in the shutdown candidate system configuration DB 203 of the storage unit 20. The operation of step S05 is executed by the subgraph enumeration unit 102 of the processing unit 10. The shutdown candidate system configuration DB 203 of the storage unit 20 accumulates and stores the shutdown candidate system configuration information D03 created by the processing unit 10.

[0101] (Step S06: Receive constraint information D04) The processing unit 10 receives the constraint information D04 from the constraint DB 204 of the storage unit 20. The operation of step S06 is executed by the shutdown candidate system configuration evaluation unit 103 of the processing unit 10.

[0102] The constraint information D04 is pre-stored in the constraint DB 204. The constraint information D04 is information related to the evaluation of the power system including the branch to which the power supply has been stopped. The constraint information D04 includes a cost case DB and a facility DB with case classification.

[0103] (Step S07: Evaluate the shutdown candidate power system graph according to the shutdown candidate system configuration information D03) The processing unit 10 evaluates the power system graph of candidates for shutdown based on the shutdown candidate system configuration information D03 created in step S04. The operation in step S07 is executed by the evaluation unit 103 of the processing unit 10 for evaluating the shutdown candidate system configuration.

[0104] The candidate system configuration evaluation unit 103 evaluates each candidate power system graph to be stopped based on the "remaining cost value" of each branch to be stopped, which is included in the constraint information D04. The "remaining cost value" is a numerical value indicating the degree of risk of using each branch as a supply route.

[0105] The shutdown candidate system configuration evaluation unit 103 also performs evaluation for each shutdown candidate power system graph based on the "individual failure probability" for each branch to which power supply is to be stopped, which is included in the constraint information D04.

[0106] (Step S08: Create system evaluation information D05) The processing unit 10 creates system evaluation information D05 based on the evaluation of the power system graph of candidates for shutdown based on the information on the candidate system configuration for shutdown D03, which was executed in step S07. The operation in step S08 is executed by the evaluation unit 103 of the processing unit 10 for evaluating the candidate system configuration for shutdown.

[0107] The shutdown candidate system configuration evaluation unit 103 creates two pieces of system evaluation information D05: system evaluation information D05 related to evaluation based on remaining cost values ​​shown in FIG. 7, and system evaluation information D05 related to evaluation based on failure probabilities shown in FIG.

[0108] (Step S9: Store the system evaluation information D05) The processing unit 10 stores the system evaluation information D05 created in step S08 in the system evaluation DB 205 of the storage unit 20. The operation of step S09 is executed by the shutdown candidate system configuration evaluation unit 103 of the processing unit 10. The system evaluation DB 205 of the storage unit 20 stores two pieces of system evaluation information D05, namely, system evaluation information D05 related to the evaluation based on the remaining cost value shown in Fig. 7 and system evaluation information D05 related to the evaluation based on the failure probability shown in Fig. 8, as system evaluation information D05.

[0109] (Step S10: Output system evaluation information D05) The processing unit 10 issues an instruction to output the system evaluation information D05 created in step S08 from the output unit 50. The processing unit 10 may issue an instruction to output the shutdown candidate system configuration information D03 and the graph information D02. The output unit 50 displays, prints out, or outputs the system evaluation information D05, the shutdown candidate system configuration information D03, or the graph information D02 as electronic data.

[0110] The above is the operation of the power system shutdown plan creation support device 1 according to this embodiment. The process by the graph conversion unit 101 may be referred to as a graph conversion step or a graph conversion procedure, the process by the subgraph enumeration unit 102 as a subgraph enumeration step or a subgraph enumeration procedure, and the process by the shutdown candidate system configuration evaluation unit 103 as a shutdown candidate system configuration evaluation step or a shutdown candidate system configuration evaluation procedure.

[0111] [1-3. Effects] (1) According to this embodiment, the power system shutdown plan creation support device 1 includes a graph conversion unit 101 that converts the configuration of a power system supplying power into a geometric model consisting of nodes and branches connecting the nodes, and creates a power system graph, a subgraph enumeration unit 102 that creates one or more shutdown candidate power system graphs, which are geometric models of a power system in which branches for stopping power supply are selected based on the power system graph created by the graph conversion unit 101, and a shutdown candidate system configuration evaluation unit 103 that evaluates the shutdown candidate power system graphs created by the subgraph enumeration unit 102 based on preset constraint information D04 that indicates constraint conditions for the power system related to the shutdown of power supply. Therefore, it is possible to provide a power system shutdown plan creation support device that supports more quickly selecting a section in a power system in which power supply is stopped, which satisfies the constraint conditions for stopping power supply.

[0112] The shutdown candidate system configuration evaluation unit 103 evaluates one or more shutdown candidate power system graphs based on the power system constraint conditions for power supply shutdown, which are included in the constraint information D04. An operator can more quickly select an appropriate section in the power system to which power supply is to be stopped, which satisfies the constraint conditions for stopping power supply, based on the evaluation of the shutdown candidate power system graphs.

[0113] (2) The constraint conditions set in the constraint information D04 include the degree of risk of using each branch that constitutes the power system as a supply route, and the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate power system graph created by the subgraph enumeration unit 102 based on the degree of risk of using it as a supply route, so that it is possible to quantitatively evaluate the shutdown candidate power system graph.

[0114] This allows an operator to more quickly select an appropriate section in the power grid where the power supply is to be stopped, depending on the importance of the constraint conditions.

[0115] (3) The constraint conditions set in the constraint information D04 include numerical information on the probability of a fault occurring for each branch constituting the power system. The shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate power system graph created by the subgraph enumeration unit 102 based on the numerical information on the probability of a fault occurring, and can therefore evaluate the shutdown candidate power system graph based on the probability of a fault occurring.

[0116] This enables workers to more quickly select sections where the power supply is to be stopped, where the probability of a power system failure occurring is low.

[0117] (4) The constraint conditions set in the constraint information D04 include at least one of constraints on the installation position of the branch, constraints based on rules or conventions that are artificial arrangements, and constraints on the phase or voltage of a node in the power system. Therefore, the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate power system graph based on a wide range of constraint conditions, not limited to electrical constraints.

[0118] This allows the operator to select a section in the power system to which power supply is to be stopped that is more suited to actual operation.

[0119] (5) The subgraph enumeration unit 102 creates one or more candidate power system graphs for suspension using a zero-suppressed binary decision diagram (ZDD). This makes it possible to create candidate power system graphs for suspension more quickly.

[0120] [2. Second embodiment] [2-1. Composition and Function] The power system shutdown plan creation support device 1 according to the second embodiment will be described. The configuration of the power system shutdown plan creation support device 1 according to the second embodiment is the same as the configuration of the power system shutdown plan creation support device 1 according to the first embodiment. In addition to the power system shutdown plan creation support device 1 according to the first embodiment, the power system shutdown plan creation support device 1 according to the second embodiment has a function of excluding equipment that is not suitable for stopping the power supply from among the equipment stored in the system configuration information D01.

[0121] The power system shutdown plan creation support device 1 according to the first embodiment creates graph information D02 based on system configuration information D01 using a graph conversion unit 101, creates shutdown candidate system configuration information D03 based on the graph information D02 using a subgraph enumeration unit 102, and evaluates the shutdown candidate system configuration information D03 based on constraint information D04 using a shutdown candidate system configuration evaluation unit 103.

[0122] The shutdown candidate system configuration evaluation unit 103 performs evaluation for each shutdown candidate power system graph related to the shutdown candidate system configuration information D03 based on the "remaining cost value" and "individual failure probability" included in the constraint information D04.

[0123] The graph conversion unit 101 of the power system shutdown plan creation support device 1 according to the second embodiment creates graph information D02 by excluding facilities that are not suitable for shutting down the power supply from among the facilities stored in the system configuration information D01.

[0124] Information on equipment that is not suitable for stopping the power supply is input by an operator via the input unit 40, and the equipment that is not suitable for stopping the power supply is excluded from among the equipment stored in the system configuration information D01 to create the graph information D02. Information on equipment that is not suitable for stopping the power supply may be set and stored in the storage unit 20 in advance, and the graph information D02 may be created by excluding the equipment that is not suitable for stopping the power supply from among the equipment stored in the system configuration information D01.

[0125] In the graph information D02, equipment that is not suitable for stopping the power supply is excluded. The subgraph enumeration unit 102 creates the stop candidate system configuration information D03 based on the graph information D02 from which the equipment that is not suitable for stopping the power supply is excluded. The stop candidate system configuration evaluation unit 103 evaluates the stop candidate system configuration information D03 based on the constraint information D04. The stop candidate system configuration evaluation unit 103 performs evaluation for each stop candidate power system graph from which the equipment that is not suitable for stopping the power supply according to the stop candidate system configuration information D03 is excluded, based on the "remaining cost value" and "individual failure probability" included in the constraint information D04.

[0126] The graph conversion unit 101 removes equipment that is not suitable for stopping the power supply from among the equipment stored in the system configuration information D01, and creates graph information D02. The subgraph enumeration unit 102 creates shutdown candidate system configuration information D03 based on the graph information D02 from which the equipment that is not suitable for stopping the power supply has been removed, and the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate system configuration information D03 using constraint information D04.

[0127] The subgraph enumeration unit 102 may be configured to exclude facilities that are not suitable for cutting off the power supply.

[0128] In this case, the graph conversion unit 101 of the power system shutdown plan creation support device 1 creates graph information D02 based on the system configuration information D01. The subgraph enumeration unit 102 creates shutdown candidate system configuration information D03 based on information on facilities that are not suitable for power supply shutdown. In the shutdown candidate system configuration information D03, branches that have facilities that are not suitable for power supply shutdown are excluded.

[0129] Information on facilities that are not suitable for stopping the power supply is input by an operator via the input unit 40, and among the branches stored in the graph information D02, branches having facilities that are not suitable for stopping the power supply are excluded to create the system configuration information D03 that is a candidate for stopping. Information on facilities that are not suitable for stopping the power supply may be set and stored in the storage unit 20 in advance, and among the branches stored in the graph information D02, branches having facilities that are not suitable for stopping the power supply are excluded to create the system configuration information D03 that is a candidate for stopping.

[0130] In the shutdown candidate system configuration information D03, branches having equipment that is not suitable for power supply shutdown are excluded. The shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate system configuration information D03 based on the constraint information D04. The shutdown candidate system configuration evaluation unit 103 performs evaluation for each shutdown candidate power system graph from which branches having equipment that is not suitable for power supply shutdown according to the shutdown candidate system configuration information D03 are excluded, based on the "remaining cost value" and "individual failure probability" included in the constraint information D04.

[0131] The subgraph enumeration unit 102 creates shutdown candidate system configuration information D03 based on the graph information D02 by excluding branches having equipment that is not suitable for stopping the power supply, and the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate system configuration information D03 using the constraint information D04.

[0132] The above is the operation of the power system shutdown plan creation support device 1 according to this embodiment.

[0133] [2-2. Effects] According to this embodiment, the graph conversion unit 101 of the power system shutdown plan creation support device 1 excludes equipment that is not suitable for power supply shutdown from among the equipment stored in the system configuration information D01, and creates graph information D02. The subgraph enumeration unit 102 creates shutdown candidate system configuration information D03 based on the graph information D02 from which the equipment that is not suitable for power supply shutdown has been excluded, and the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate system configuration information D03 based on the constraint information D04, and thus evaluation is performed on the power system according to the shutdown candidate system configuration information D03 from which the equipment that is not suitable for power supply shutdown has been excluded.

[0134] Alternatively, according to this embodiment, the subgraph enumeration unit 102 of the power system shutdown plan creation support device 1 creates shutdown candidate system configuration information D03 by excluding branches having equipment that is not suitable for power supply shutdown based on the graph information D02, and the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate system configuration information D03 based on the constraint information D04, thereby evaluating the power system according to the shutdown candidate system configuration information D03 from which branches having equipment that is not suitable for power supply shutdown have been excluded.

[0135] This allows the evaluation of the shutdown candidate system configuration information D03 that shuts down the equipment desired by the worker to be presented, and more appropriately supports the worker in selecting the branch to shut down the power supply. The worker can easily avoid shutting down the power supply of undesired equipment.

[0136] 3. Other embodiments Although the embodiments including the modified examples have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents as well as in the scope and gist of the invention. The following is an example.

[0137] (1) The constraint conditions related to the constraint information D04 stored in the constraint DB 204 may include information regarding the presence of a load that will be subject to a power outage if the power supply of the branch selected as the branch to which the power supply is to be stopped is stopped.

[0138] The candidate system configuration evaluation unit 103 evaluates the candidate power system graph to be stopped based on the constraint conditions including information on the presence of a load that will be subject to a power outage if the power supply of the selected branch is stopped, which is set in the constraint information D04. The candidate system configuration evaluation unit 103 evaluates the candidate power system graph to be stopped, which has a load that will be subject to a power outage if the power supply of the branch selected as the branch to be stopped is stopped, as being unselectable.

[0139] This allows the power system shutdown plan creation support device 1 to support more quickly selecting an appropriate section in the power system for which power supply is to be stopped, which satisfies the constraint conditions for stopping the power supply. By stopping the power supply of the selected branch, the operator can avoid selecting a branch in the shutdown candidate power system graph in which a load that will cause a blackout exists, as a branch for which power supply is to be stopped.

[0140] (2) The constraint conditions related to the constraint information D04 stored in the constraint DB 204 may include, in addition to the branch selected as the branch for which the power supply is to be stopped, information regarding other branches for which it is preferable to stop the power supply.

[0141] When the constraint conditions set in the constraint information D04 include stopping the power supply of other branches in addition to the branch selected as the branch that will stop the power supply, the shutdown candidate system configuration evaluation unit 103 evaluates the shutdown candidate power system graph based on whether the other branches have been selected as the branches that will stop the power supply.

[0142] This allows the power system shutdown plan creation support device 1 to support more quickly selecting an appropriate section in the power system to which power supply is to be stopped, which satisfies the constraint conditions for stopping the power supply. The operator can quickly select other branches to which it is preferable to stop the power supply, together with the branch selected as the branch to which the power supply is to be stopped.

[0143] (3) The constraint conditions included in the constraint information D04 are not limited to those described above. The constraint conditions included in the constraint information D04 may be any constraint conditions.

[0144] (4) In the above embodiment, the storage unit 20 is provided inside the power system shutdown plan creation support device 1. However, the storage unit 20 may be provided outside the power system shutdown plan creation support device 1. For example, the storage unit 20 may be provided in a server or cloud outside the power system shutdown plan creation support device 1. [Explanation of symbols]

[0145] 1. Power system outage planning support device 10 Processing section 101 Graph conversion unit 102...Subgraph enumeration unit 103: Shutdown candidate system configuration evaluation unit 20...Storage section 201...System configuration DB 202 Graph DB 203...Suspension candidate system configuration DB 204...constraint DB 205···System evaluation database 40 Input section 50 Output section

Claims

1. a graph conversion unit that converts a configuration of a power system that supplies power into a geometric model consisting of nodes and branches connecting the nodes, and creates a power system graph; a subgraph enumeration unit that creates one or more candidate power system graphs for stopping, the candidate power system graphs being geometric models of the power system in which branches for stopping power supply are selected based on the power system graph created by the graph conversion unit; and a shutdown candidate system configuration evaluation unit that evaluates the shutdown candidate power system graph created by the subgraph enumeration unit based on preset constraint information indicating a constraint condition of the power system related to the shutdown of power supply. A power system outage planning support device.

2. the constraint conditions set in the constraint information include a degree of risk of using each of the branches constituting the electric power system as a supply route, the shutdown candidate system configuration evaluation unit evaluates the shutdown candidate power system graph created by the subgraph enumeration unit based on the degree of risk of using the shutdown candidate power system graph as a supply route; The power system shutdown plan creation support device according to claim 1 .

3. the constraint condition set in the constraint information includes numerical information on a probability of occurrence of a fault for each of the branches constituting the power system, the shutdown candidate system configuration evaluation unit evaluates the shutdown candidate power system graph created by the subgraph enumeration unit based on the numerical information on a probability of occurrence of a fault; The power system shutdown plan creation support device according to claim 1 .

4. The constraint conditions set in the constraint information include at least one of a constraint on an installation position of the branch, a constraint based on a rule or a custom which is an artificial agreement, and a constraint on a phase or a voltage of the node in the power system. The power system shutdown plan creation support device according to claim 2.

5. the suspension candidate system configuration evaluation unit evaluates, as unselectable, the suspension candidate power system graph in which a load that will be subjected to a power outage by stopping the power supply to the branch selected as the branch to be suspended is present; The power system shutdown plan creation support device according to claim 2.

6. the stop candidate system configuration evaluation unit evaluates the stop candidate power system graph based on whether the other branch is selected as a branch to stop power supply, when the constraint conditions set in the constraint information include stopping power supply of the other branch together with the branch selected as a branch to stop power supply; The power system shutdown plan creation support device according to claim 2.

7. The graph conversion unit creates a power system graph by excluding equipment that is not suitable for stopping the power supply. The power system shutdown plan creation support device according to claim 1 .

8. On the computer, a graph transformation step of transforming a configuration of a power system that supplies power into a geometric model consisting of nodes and branches connecting the nodes, and creating a power system graph; a subgraph enumeration step of creating one or more candidate power system graphs for stopping, the candidate power system graphs being geometric models of the power system in which branches for stopping power supply are selected based on the power system graph created by the graph conversion step; a shutdown candidate system configuration evaluation step of evaluating the shutdown candidate power system graph created in the subgraph enumeration step based on preset constraint information indicating constraint conditions of the power system related to the shutdown of power supply; A computer program for a power system outage planning support device.

9. a graph transformation step of transforming the configuration of a power system supplying power into a geometric model consisting of nodes and branches connecting said nodes, and creating a power system graph; a subgraph enumeration step of creating one or more candidate power system graphs for stopping, the candidate power system graphs being geometric models of the power system in which branches for stopping power supply are selected based on the power system graph created by the graph transformation step; and a shutdown candidate system configuration evaluation step of evaluating the shutdown candidate power system graph created by the subgraph enumeration step based on preset constraint information indicating constraint conditions of the power system related to the shutdown of power supply. A method for supporting the creation of power system outage plans.

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