JPH11289662A - Load interchange method in power distribution system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure a power for to interchanging and supply reserves, by using object knowledge expression or the like due to an expart system for determining cascade interchange when the capacity of the adjacent power supply of a section to be interchanged is insufficient. SOLUTION: When an accident occurs at a point F on the feeder of a power supply G1 , a total amount of lead L1 of a section to be interchanged being detected by performing search in all directions from one node in the section to be interchanged is compared with sum ΣRG2 of the supply reserves of the group of adjacent power supples G2 . As a result, when cascade interchange is required, the adjacent power supply G2 is set to a cascade target power supply. Then, a power supply that is adjacent to the power supply G2 and has large supply reserves is set to a cascade power supply G3 , the sum of the sum ΣRG2 of the supply reserves of the group of adjacent power supplys G2 and supply reserves RG3 of the cascade power supply G3 is compared with the total amount of load L1 of the section to be interchanged. As a result, when cascade interchange can be made, switching means CB, CB1 , and CB2 for coordinating the adjacent power supplies G1 -G3 and the switching state of a switching means S1 on the feeder are determined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a function added to a control computer or the like in a distribution office, for example, in which a configuration of a distribution system, a section to be interchanged, each load capacity, each power supply and its capacity are given. When the capacity of the adjacent power supply in the section to be accommodated becomes insufficient as the first stage of load accommodation,
An expert system (hereinafter abbreviated as ES if necessary) is a method for creating a so-called ball-swap method using an object knowledge expression and a search method using the object knowledge expression. The present invention relates to a load accommodating method in a distribution system in which a section to be accommodated is optimally shared by adjacent power sources using an algorithm (hereinafter, abbreviated as GA as necessary).

[0002]

2. Description of the Related Art The so-called ball-swapping has already been automated, but conventionally, the ball-swapping has been performed using a heuristic search method using an array developed from a power database. I was looking for power. Further, in the section to be interchanged, the section to be interchanged is collectively shared by the power source having the largest capacity without performing the optimal division.

However, in this conventional method, the expression of data is complicated, and it is difficult for both a maker who creates a load accommodation program and a user who uses the program to create or modify the program. In addition, since the section to be accommodated is shared by the power supply having the largest capacity, the accommodating section may not be able to be provided if the power supply capacity is insufficient. Furthermore, it has been difficult in the past to cope with a larger-scale flexible section.

On the other hand, in the current situation where power distribution automation is promoted, when determining the power supply feeder, which is the first stage of load accommodation, which power source supplies power under the restrictions of the power distribution network such as the radial load and power supply capacity restrictions. It is necessary to determine whether to do this, and this can be considered as a kind of combinatorial optimization problem called a graph partitioning problem.

Although various methods have been proposed to solve this problem, GA has been noted as an effective method for the combinatorial optimization problem, and the inventors have proposed a power supply feeder for each load in load interchange. Have already proposed the application of GA to the decision problem of Fukuyama (Fukuyama et al., "Application of Genetic Algorithm to Load Interchange Problem", IEICE Transactions B, 11).
Vol. 4, No. 4, April 1994). A method of determining load accommodation using a GA is disclosed in Japanese Patent Application Laid-Open No. 7-203630 (Japanese Patent Application No.
No. 12098).

[0006] Here, GA is a kind of optimization technique that simulates the growth mechanism of organisms by focusing on selection and transmission of genetic information in the natural world. Those with low are selected naturally,
This model simulates a process in which highly adaptable ones survive to the next generation and form the next generation through crossover and mutation as genetic manipulation. This GA does not need to use the gradient of the evaluation function in the optimization, and it is attracting attention as an effective one for the combination optimization problem due to the advantage of speeding up by parallel processing, etc. It has begun to be applied to various fields, such as chemical engineering.

Therefore, the first aspect of the present invention provides, as the first stage of load accommodation, when the capacity of the adjacent power source in the section to be accommodated is insufficient, the ES uses an object knowledge expression and a search method using the object knowledge expression. The second invention proposes a method of creating an abrupt accommodation method, and the second invention performs an actual accommodation calculation using a GA as a subsequent second step, and optimally shares the accommodated section with an adjacent power supply. It is an object of the present invention to propose a load accommodating method in a distribution system as described above and to solve various problems of the above-described conventional technology.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 provides a configuration of a power distribution system, a section where power is supplied, a load capacity, a power supply, and a power supply capacity. A load accommodating method for deciding a power feeder for each load by turning on / off the switching means for performing power transmission to the accommodating section, and accommodating power from the section other than the accommodating section to the accommodating section. When the total load amount of the section exceeds the total supply reserve capacity of the adjacent power supply group, the nodes constituting the power distribution system in the ball-adjusting method for sequentially supplying power from another adjacent power supply group adjacent to the adjacent power supply group Is expressed using object knowledge, a search is performed in all directions from one node in the flexible section to detect the total load amount of the flexible section and the first adjacent power supply group, and the total load amount of the flexible section and First adjacent power supply group A comparison is made with the total supply reserve to determine the necessity of ballistic accommodation. If it is determined that ballistic accommodation is necessary, the power supply with the smallest supply reserve in the first adjacent power supply group is determined as the power supply targeted for collision. , A second power supply adjacent to this
The power supply having the largest supply reserve among the adjacent power supplies is searched for as the first ballistic power supply, and the sum of the supply reserve power of the first adjacent power supply group and the supply reserve of the first ballistic power supply is calculated; Comparing the sum of the load amounts of the sections to be interchanged with each other to determine whether or not the one-stage ball collision can be accommodated, and when it is determined that the one-stage ball collision can be accommodated, the opening / closing means for interconnecting each adjacent power supply and the opening / closing means on the feeder Is determined, and when it is determined that the one-stage collision is impossible, the power supply having the largest supply reserve among the third adjacent power sources adjacent to the first collision power source is set to the second power source. A search is made for a collision power source, and the sum of the reserve reserve of the first adjacent power source group and the first
And the sum of the reserve power of the second ball-shaped power supply and the sum of the load amounts of the sections to be interchanged to determine whether or not the two-stage ball-throwing is possible, and it is determined that the two-stage ball-throwing is possible. In this case, the open / close state of the open / close means for interconnecting the adjacent power sources and the open / close means on the feeder is determined.

According to a second aspect of the present invention, based on the one-stage or two-stage ball-swapping method determined according to the first aspect of the present invention, power is supplied from each of the adjacent power sources while considering the supply reserve of the adjacent power source. The loads to be supplied are gradually and radially determined stochastically, and the load accommodating state with the power supply determined for all loads is converted into a string representation to generate initial strings. On the other hand, the fitness is evaluated based on the supply reserve of the power supply, and a string having a high fitness is selected, and then the intersection is performed with the boundary of the adjacent load in the string representation as an intersection position. As a result, the string exists in the distribution system. Modify the string if a dead string is generated that violates a constraint, as well as one of the string positions in the string representation.
The flexible section is optimally assigned to each power supply by a genetic algorithm that performs a mutation operation by changing the direction of the power supply of the only load so as to satisfy the constraint condition by converting bits.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, an embodiment of the invention described in claim 1 will be described. First, the concept of a ball-and-shoot interchange will be described.
In the load accommodation, when a section to be accommodated occurs due to a feeder accident or the like, power is supplied from a feeder adjacent to the section to be accommodated by an interconnection breaker. Here, if the sum of the reserve powers of the adjacent power supplies exceeds the sum of the load amounts of the sections to be interchanged, the power can be retransmitted by a normal interchange method. However, when the sum of the reserve reserves of the adjacent power supplies is less than the total load amount of the section to be interchanged, the power supply capacity is insufficient, and power cannot be transmitted by a normal interchange method.

[0011] As described above, when the accommodation from only the adjacent power supply in the section to be interchanged is insufficient (the sum of the reserve power of the adjacent power supply <the total amount of the load in the section to be interchanged) as described above, the collision of the adjacent power supply is considered. This is a method in which power is exchanged from another adjacent power supply, and can be generally considered as an accommodation method in the event of a major accident. Here, “how much power should be exchanged from which power source” is an optimization problem, and ball collision is a large-scale combination optimization problem. Therefore, in the first aspect of the present invention, a heuristic method employed in a known practical load interchange system is used, and this is realized by an ES (search processing system using an object knowledge expression).

[0012] Figure 1 is a diagram for explaining the concept of the ball突融through a one-stage, FIG. 1 (A) interconnection can connects the power supply G ₁ and a power supply G ₂ other than the interconnection circuit breaker CB ₁ FIG. 1B shows a case where there is a system breaker CB and a case where there is no interconnecting breaker CB. Now, the accident occurred at a point F on the feeder of the power supply G _1. At this time, the power to be supplied power to the flexible section L ₁ G ₂ (first adjacent power G _1). As shown in FIG. 1 (A), (B), one stage ball突融communication, since the power supply G ₂ is responsible for power supply to the flexible section L _1, a portion of the load for which you are responsible (section L ₃ ),
Further, the power supply G ₃ (a power supply adjacent to the power supply G _{2 and} a _second power supply adjacent to the power supply G ₁ ) is assigned.

For this purpose, first, the most upstream interconnection breaker CB ₁ between the power sources G ₁ and G ₂ is closed, and is located downstream of the interconnection breaker CB _{1 and} between the power sources G ₂ and G ₃ . some interconnection circuit breaker CB ₂ is closed. As shown in FIG. 1 (A), the in the case where the power supply G ₁ and a power supply G ₂ other than the interconnection breaker CB ₁ has interconnection possible interconnection circuit breaker CB is supplied spare power G _2, G ₃ to average as much as possible the forces, the switch S ₁ on the feeder of the power supply G ₂ located between the interconnection circuit breaker CB ₁ and CB ₂ opened. on the other hand,
As shown in FIG. 1 (B), the in the absence of a power supply G ₁ and a power supply G ₂ is interconnection possible interconnection circuit breaker CB in addition to interconnection breaker CB ₁ is interconnection on the feeder supply G ₂ The switch S ₁ as far upstream as possible within the range downstream of the point (FIG. 1 (A)
Open). Thus, it is possible to maximize the reserve capacity of the power supply G _2. At this time, interconnection breaker power G ₂ can be shared or it is impossible to share a part of the share of the power supply G ₁ from interconnection point, the power supply G ₃ some of the load of the power supply G ₂ If CB ₂ is not found, it is determined that one-stage ballistic accommodation is impossible.

[0014] Figure 2 is a diagram for explaining the concept of the ball突融through two stages, FIG. 2 (A) capable of interconnection with a power supply G ₁ and a power supply G ₂ other than the interconnection circuit breaker CB ₁ FIG. 2B shows a case where there is the interconnection breaker CB and a case where there is no interconnection breaker CB. In general, the two-stage ballistics are used when the size of the feeder is large and the one-stage ballistics cannot be accommodated. As shown in FIGS. 2 (A) and 2 (B), in the two-stage ball-and-shoot interchange, a part (section L ₃ ) of the load assigned to the power supply G ₂ is a power supply G ₃ (adjacent power supply to G ₂ ). The power supply G ₁ is assigned to a second adjacent power supply, and a part of the load (section L ₅ ) assigned to the power supply G ₃ is also assigned to a power supply G ₄ (an adjacent power supply to G ₃ , This is a method for ₁ to be assigned to the third adjacent power supply.

Firstly Therefore, the power G _1, interconnection circuit breaker CB ₁ the most upstream among G ₂ is closed, between the power supply G _2, G ₃ In the downstream of the interconnection circuit breaker CB ₁ some interconnection circuit breaker CB ₂ is closed. Further, the power supply G _3, interconnection circuit breaker CB ₃ in between G ₄ In the downstream of the interconnection circuit breaker CB ₂ is closed. FIG.
(A), the other than interconnection breaker CB _1, when between power G _1, G ₂ has interconnection possible interconnection circuit breaker CB is downstream thereof, the power supply G _2, G ₃ to average as possible reserve capacity, the switch S ₁ on the feeder of the power supply G ₂ located between the interconnection circuit breaker CB ₁ and CB ₂ is opened, the interconnection circuit breaker CB ₂ and CB ₃ the switch S ₂ on the feeder power G ₃ and open in between. On the other hand, as shown in FIG. 2 (B), when there is no interconnection possible interconnection circuit breaker CB and power G ₁ and a power supply G ₂ other than the interconnection circuit breaker CB ₁ is reserve capacity of the power supply G ₂ the so to maximize, the switch S ₁ in as much as possible upstream in the downstream of the range from the connecting point of the power supply G ₂ feeder is opened, the power supply G located between the interconnection circuit breaker CB ₂ and CB _{3 3} of the switch S ₂ on the feeder is opened (similar to results in FIG. 2 (a)). At this time, interconnection breaker power G ₂ can be shared or it is impossible to share a part of the share of the power supply G ₁ from interconnection point, the power supply G ₃ some of the load of the power supply G ₂ If CB ₂ is not found or power supply G ₄
There when the interconnection circuit breaker CB ₃ that can share some of the load of the power supply G ₃ not found, it is determined that it is impossible ball突融through two stages.

Next, a specific method of the ball-shock accommodation will be described. The distribution lines are arranged in the order of power supply, feeder breaker, load, switch (interconnection breaker), load, switch, ..., load, and by performing search processing using these as nodes, Power supply, interconnection breaker, switchgear can be determined. The specific processing is as follows.

(1) Search processing 1: Search downstream from the power supply end for each distribution line Search is performed downstream from the power supply end for each distribution line. Here, search is performed for all distribution lines, and node information is collected. There are five types of nodes: power supply, load, feeder breaker, interconnection breaker, and switch. As a result of the search, the following information is obtained for each distribution line / node. • Total load, supply reserve • Current supply power • Upstream load node number, downstream load node number • Number of interconnected circuit breakers, number of interconnected circuit breakers • Number of nodes and node numbers in flexible sections

(2) Searching process 2: Searching in all directions from one node in the flexible section From one node in the flexible section in all directions,
As a result, the following information on the interchanged section is obtained. - loading of the flexible segment sum L _1, the first adjacent power (G ₂₎ group

(3) Necessity determination of ballistic accommodation Whether or not ballistic accommodation is necessary is determined. Supply reserve R of each power supply G ₂
Determining by the sum of G ₂ and the (ΣRG ₂₎ and the load amount sum L ₁ of the flexible section. That is, if ΣRG ₂ ≧ L ₁ , the normal accommodation processing is sufficient, and if ΣRG ₂ <L ₁ , it is determined that ballistic accommodation is necessary. As a result, if it is determined that ballistic accommodation is necessary, the following processing is performed.

(4) Sorting of Power Source Candidates for Collision The adjacent power sources in the section to be interchanged are rearranged in ascending order of reserve power.

(5) Independent execution of single-stage collision accommodation Among the collision-target power supply candidates sorted in (4) above, the first adjacent power supply is a collision-target power supply for single-stage collision accommodation (a target collision accommodation power supply). ) and G _2. Of the adjacent power ball collision target power G _2, a power supply with a maximum reserve capacity and balls突電source G _3, at the same time, determine whether the ball突融communication by the reserve force of the power supply G ₃ (RG ₃₎ I do. That is, if (ΣRG ₂ + RG ₃ ) ≧ L ₁ , the one-stage collision is possible. If (ΣRG ₂ + RG ₃ ) <L ₁ , it is determined that the one-stage collision is not possible.

As a result, if it is determined that the one-stage collision is not possible, the power source having the next smaller supply reserve is determined as the collision target power source G ₂ according to the sorting result of (4). I do. When the one step ball突融communication is judged to be the interconnection circuit breaker for performing stage ball突融through by the current ball collision target power G ₂ and ball突電source G _3, locate the separation switch, these If found, all processing ends. If not found, according to further sort result of (4), then power supply having a small reserve capacity as Tama突target power G _2, performs the processing described above. Also interconnection circuit breaker all power sorted as ball impact target power G ₂ (4), when the separation switch can not be determined singly executing the first stage ball突融communication fails and multiple execution of one step ball突融communication To perform the following processing (6).

[0023] (6) and ball collision target power G ₂ for stage ball突融through the top of the power supply of the power source sorted by one step ball突融through multiple executions of the above-mentioned (4). Among the neighboring power of the ball collision target power G _2, a power supply with a maximum reserve capacity with the ball突電source G _3. The interconnection circuit breaker for performing stage ball突融through by the current ball collision target power G ₂ and ball突電source G _3, locate the separation switches, if found these, according to the sort result of (4) one The execution of one-stage ball abutment is added one by one, and when it becomes possible to supply the entire load in the section to be accommodated, all the processes are terminated assuming that a plurality of executions of the one-stage ball abutment have succeeded. If the full load in the section to be interchanged cannot be supplied even if the one-stage ball interchange is performed for all the remaining ballistic target power supplies, the two-stage ball The process proceeds to the next process (7) in order to consider independent execution of the sudden accommodation.

[0024] (7) and ball collision target power G ₂ for the two-stage ball突融through the power head of the power sorted through a double ball突融through a single execution of the above (4). Power with the maximum reserve capacity among the adjacent power supply of the ball collision target power G ₂ is a first ball突電source G _3, maximum reserve capacity among the adjacent power supply of the ball collision target power G ₃ power with the second ball突電source G _4. At the same time, the reserve force of the power supply G ₃ (R
G ₃ ) and the supply reserve (RG ₄ ) of the power supply G ₄ determine the flexibility. In other words, if (ΣRG ₂ + RG ₃ + RG ₄ ) ≧ L ₁ , two-stage ballistic accommodation is possible. If (ΣRG ₂ + RG ₃ + RG ₄ ) <L ₁ , two-stage ballistic accommodation is not possible. judge.

As a result, it is determined that the two-stage ball-throwing accommodation is impossible.
In the case of the following, according to the sorting result of (4) above,
A power supply having a small reserve reserve is a power supply G that is a target for collision._Twoage
To make a similar determination. It has been determined that two-tiered ballistics can be accommodated.
In this case, the current target power source G_TwoAnd the power supply G_Three, G_Four
Interconnected circuit breaker and separation switch for two-stage
Search for switches and terminate all processing if found
I do. If not found, further sort according to (4)
Power supply with the next smallest supply reserve
Source G _TwoThe above processing is performed. Sorted by (4)
All of the power supplies are targeted power supplies G_TwoAs an interconnected circuit breaker,
If the separation switch cannot be determined,
The single execution failed, and the two-stage
Go to the next process (8) to consider multiple executions
Transition.

(8) Independent execution of two-stage ballistics and multiple executions of one-stage ballistics Among the power sources sorted in the above (4), the first power source is a power source G for the two-stage ballistics. _2. This power source G
Power with the maximum reserve capacity among the _two adjacent power supply first ball突電source G _3, up to the second ball power with reserve capacity in one of the adjacent power supply of the ball突電source G ₃ as突電source G _4, two-stage ball突融communication interconnection circuit breaker for performing, locate the separation switches, if found these, (4) according to the sort result of the addition of the execution of one by one single stage ball突融communication At this point, when it becomes possible to supply the entire load in the accommodated section, all the processes are terminated assuming that the single-stage ball-shock interchange and the single-stage ball-shake interchange have been successfully executed. If the full load in the section to be accommodated cannot be supplied even if the single-stage ball-swap is added to all the remaining ball-jump target power supplies, the two-stage ball-swap alone and the single-stage ball-swap can be executed multiple times. Is determined to have failed, the process proceeds to the next process (9) to consider a plurality of executions of the two-stage ball collision.

(9) A plurality of executions of the two-stage ball-shock interchange The top power source among the power sources sorted in the above-mentioned (4) is the ball-gather target power source G ₂ for the two-stage ball-shake interchange,
Power with the maximum reserve capacity among the _two adjacent power supply first ball突電source G _3, up to the second ball power with reserve capacity in one of the adjacent power supply of the ball突電source G ₃ As the power supply G ₄ , an interconnection breaker and a separation switch for performing the two-stage ball collision are searched, and if these are found, the execution of the two-stage ball collision is performed one by one according to the sorting result of (4). Then, at the time when the entire load amount in the section to be accommodated can be supplied, all the processes are terminated assuming that the multiple execution of the two-stage ball abutment has succeeded. Even if two-stage ballistics are added to all remaining ballistic target power sources, if the full load in the section to be accommodated cannot be supplied, multiple executions of the two-stage ballistics are considered to have failed and all Is completed.

FIG. 3 shows a model power distribution system simulated by applying this embodiment.
4 simulates a case where an accident has occurred at the point F of the feeder and the hatched portion has become a flexible section. In the simulation, the load in the section to be accommodated is No. 3 and No. 5
No. is used as a power source. 1, No. Two stages of ballistic accommodation were performed from the power source of No. 2. As a result, the switches SW1,
By opening SW2 and closing circuit breakers CB1 and CB2, No. No. 2 feeder load No. No. 1 is partially assigned to the feeder. The feeder load of No. 3 is No. No. 2 is partially assigned to the feeder, so that the ballistic accommodation is performed and It was confirmed that the feeder of No. 3 could also be used as a power source for interchange.

Next, an embodiment of the present invention will be described. According to the first aspect of the present invention, the power supply for the section to be accommodated is determined by one-stage or two-stage ballistic interchange using the ES. In this case, the actual accommodation calculation for optimally sharing the data is executed by the GA. That is, the roles of the ES and the GA are as follows. ES: Find the power supply for the section to be interchanged and its supply reserve, including the measures for the ballistic interchange. GA: Load is optimally shared for each power supply determined by ES. A so-called accommodation calculation is performed.

The gist of the invention according to claim 2 is a specific procedure for determining the load sharing by the GA on the premise of the ball abutting method according to the invention described in claim 1. That is, the reserve capacity RG ₂ ball collision target power G ₂ and power supply capacity, the voltage at the location of the interconnection circuit breaker for each power supply G ₂ as a power supply voltage, to perform load interchange calculation by GA.

Here, the determination of the power supply feeder of each load in the load interchange can be formulated as a graph division problem. In this case, the objective function and the constraint condition are defined and formulated as follows. And

A. Objective function Minimize the total load of the load nodes that fail and average the power supply reserve B. Restrictions (1) Radial restriction There must be one power supply to each load, and no loop operation is performed. (2) Power supply capacity restriction The sum of the load amounts of the load nodes belonging to the divided subgraph must not exceed the power supply capacity. (3) Feeder capacity restriction The current flowing through each feeder must not exceed the capacity limit. (4) Voltage restrictions Each load node voltage must be within the upper and lower limit value range.

Next, a description will be given of a formulation by GA for determining the load distribution to each power supply. The contents are described in JP-A-7-203630 (Japanese Patent Application No. Hei 6-12098).
No.). (1) String representation method A string corresponds to a genotype, and a solution is represented by a one-dimensional character array. In GA, an expression method is required in which the string length is as short as possible, and it is difficult to generate a dead string that violates the above-described constraint by string manipulation. In consideration of this condition, in the present embodiment, a string having the length of the number of loads in the section to be accommodated is used, and each string position is set to a power supply / load number on the upstream side of each load.
The string representation shown in base was used. According to this expression, the numerical value that can be used for each string position can be limited, and the number of dead strings generated by the string operation can be reduced as compared with the conventional method of expressing the ON / OFF state of each switch in a binary system. Since the length is also shortened, it is possible to quickly find the optimal solution.

(2) Initial String Generation Method A heuristic algorithm is used to stochastically determine the shared load according to the power supply reserve. In other words, the load is allocated as much as possible to the power supply having a large reserve reserve, and the load to be supplied with power by each neighboring power supply is gradually and stochastically determined in consideration of the reserve reserve of the neighboring power supply, An initial string is generated by converting the load accommodation state in a state where the power supply is determined for all loads into a string expression. As a result, initial values dispersed near a solution close to the optimal solution can be given, and high-speed optimization can be performed.

(3) Evaluation and Selection of Strings Strings are evaluated for fitness based on the reserve capacity of power supply, and strings with high fitness are selected. That is, the string is evaluated so as to have a high fitness when the supply reserve is averaged and to give a large penalty when the supply reserve is negative. In addition, linear scaling (DEGoldber
g, Genetic Algorithms in Search, Optimization, and
MachineLearning, Addison-by Wesley, 1989)
Was used. String selection method is Remainder Stochastic Sampl, which combines deterministic method and stochastic method.
ing with Replacement (DEGoldberg, Genetic Algori
thms in Search, Optimization, and Machine Learnin
g, Addison-by Wesley, 1989).

(4) String operation a. Intersection Here, a one-point intersection (simple intersection) is used, and in the case of using the string expression, the intersection is defined as the intersection position between the load at the intersection position and the adjacent load, and the load accommodation state is partially changed to another accommodation state. It means to switch to the state,
This corresponds to an operation of creating a child chromosome by rearrangement of two parent chromosomes. Although use of a multipoint intersection is conceivable, a plurality of sub-systems having no power supply may be created due to the intersection, which complicates a correction operator described below. Therefore, a simple one-point intersection was used here.

B. Correction Operator The correction operator means that when a dead string is generated by an intersection, the string is partially corrected to satisfy the constraint. Specifically, when a partial system having no power supply occurs due to the intersection, the string is corrected so that the partial system is connected to the power supply feeder adjacent to the partial system having the largest reserve power.

C. Mutation Mutation is equivalent to an operation of changing a gene with a certain probability, and has a significance of searching for a neighborhood of a solution obtained by crossing, thereby preventing a drop to a local solution. Specifically, this is conversion of one bit at each string position, and in the load accommodation problem, it means that the power supply of only one load is changed. It is possible to change the power supply of only one load, i.e. change the direction upstream of the load, while satisfying the radial and transit route constraints that a load and its upstream loads must both have the same power supply. Are only the loads adjacent to the loads being supplied from different power supply feeders. Therefore, only such a load enables mutation.

FIG. 4 shows a model power distribution system simulated by applying the embodiment of the present invention.
No. 4 simulates a case where an accident has occurred at the point F of the feeder and the hatched portion has become a flexible section. The parameters of GA are cross probability: 0.5, mutation probability: 0.
01, the number of strings: 50, and simulation of ballistic accommodation was performed. Note that these parameter conditions can be applied to various systems without any problem. In the simulation, the load in the section to be accommodated is No. 3 and No. No. 5 as a power source. 1, No. Two stages of ballistic accommodation were performed from the power source of No. 2. As a result, by opening the switches SW1 and SW2 and closing the circuit breakers CB1 and CB2, No. 2 feeder load No. No. 1 is partially assigned to the feeder. 3 feeder load N
o. No. 2 is partially assigned to the feeder, so that the ballistic accommodation is performed and The third feeder can also be used as a power source to be interchanged. Further, as a result of the section to be accommodated being optimally divided by the GA, the switch SW3 is opened, whereby the No. 3 and No. It was confirmed that the load was assigned to 5 feeders.

[0040]

As described above, according to the first aspect of the present invention, the E
In S, the power supply for the section to be accommodated and its reserve reserve are obtained, including the handling of the ballistic accommodation, and the invention according to claim 2 thereafter uses the power supply obtained by ES to determine each power supply. The load is optimally shared by the GA with respect to the power supply. As a result, it is possible to maximize the capacity of the interchange power supply and to distribute the load such that the section to be interchanged is minimized, thereby performing highly reliable load interchange.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a one-stage ball-throwing accommodation according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram of a two-stage ball-adjustment according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a model power distribution system obtained by performing a simulation by applying the embodiment of the first aspect of the present invention;

FIG. 4 is a diagram showing a model power distribution system simulated by applying the embodiment of the invention of claim 2;

[Explanation of symbols]

_{G 1, G 2, G 3} , G 4 power _{CB, CB 1, CB 2,} CB 3 consecutive system breaker L ₁ the flexible section _{L 2, L 3, L 4} , L 5 sections S _1, S ₂ switch F Accident point

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tohoku Fujita 1-1, Tanabe-Nitta, Kawasaki-ku, Kawasaki, Kanagawa Prefecture Inside Fuji Electric Co., Ltd. (72) Inventor Yoshikazu Fukuyama 1, Tanabe-Nitta, Kawasaki-ku, Kawasaki-ku, Kanagawa Prefecture No. 1 Inside Fuji Electric Co., Ltd.

Claims (2)

[Claims] When a configuration of a power distribution system, a section to be supplied with power supply, each load capacity, each power supply, and a power supply capacity are given, opening and closing means are turned on and off to perform retransmission of power to the section to be supplied. Determine the power supply feeder for each load, a load accommodation method for accommodating power from the non-interchangeable section to the interchangeable section, where the total load amount of the interchanged section exceeds the total supply reserve of the adjacent power supply group, In a ball-swap method for sequentially supplying power from another adjacent power supply group adjacent to the adjacent power supply group, a node constituting a power distribution system is expressed using object knowledge, and all nodes from one node in the interchanged section are The search is performed in the direction to detect the total load amount and the first adjacent power supply group in the interchanged section, and compares the total load amount in the interchanged section with the total supply reserve capacity of the first adjacent power supply group to determine whether or not the ballistic interchange is available. Judgment of necessity and accommodation of the ball If it is determined that it is necessary, the power supply with the smallest supply reserve in the first adjacent power supply group is set as a collision target power supply, and the power supply with the largest supply reserve among the second adjacent power supplies adjacent to this collision target power supply As a first collision power supply, and comparing the sum of the supply reserve power of the first adjacent power supply group and the supply reserve power of the first collision power supply with the total load amount of the section to be interchanged. It is determined whether the one-stage ball collision is possible or not, and when it is determined that the one-stage ball collision is possible, the open / close state of the opening / closing means for interconnecting each adjacent power supply and the opening / closing means on the feeder is determined. If it is determined that the power supply is not possible, a power supply having the largest supply reserve among the third adjacent power supplies adjacent to the first ballistic power supply is searched for as the second ballistic power supply, and the first adjacent power supply is searched for. The sum of the supply reserve of the group and the supply reserves of the first and second bump power supplies; A comparison is made between the load sum of the sections to determine whether or not the two-stage ball-thrust can be accommodated. If it is determined that the two-stage ball-thrust interchange is possible, the opening / closing means for interconnecting the adjacent power sources and the opening / closing means on the feeder are determined. A load accommodating method in a distribution system, characterized by determining an open / closed state of a load. 2. The method according to claim 1, wherein a load supplied by each adjacent power supply is radiated while taking into consideration the supply reserve of the adjacent power supply, based on the one-stage or two-stage ball-adjustment method determined. It is determined stochastically gradually, the load accommodation state in the state where the power supply is determined for all loads is converted into a string representation to generate initial strings, and then, for these initial strings,
The fitness is evaluated based on the supply reserve of the power supply, and a string having a high fitness is selected. Thereafter, the intersection is performed with the boundary between adjacent loads in the string representation as an intersection position. As a result, the constraint conditions existing in the power distribution system are obtained. If a dead string is generated that violates
A genetic algorithm that performs a mutation operation by changing the direction of the power supply of the only load so as to satisfy the above constraint by converting one bit of the string position in the string representation, to optimize the flexible section for each power supply A load accommodating method in a distribution system, characterized by sharing.