CN117996839B - Island division method and system for improving reliability of power distribution network - Google Patents
Island division method and system for improving reliability of power distribution network Download PDFInfo
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- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
- H02J3/466—Scheduling the operation of the generators, e.g. connecting or disconnecting generators to meet a given demand
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- H02J2310/00—The network for supplying or distributing electric power characterised by its spatial reach or by the load
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- H02J2310/58—The condition being electrical
- H02J2310/60—Limiting power consumption in the network or in one section of the network, e.g. load shedding or peak shaving
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Abstract
The invention provides an island division method and system for improving reliability of a power distribution network, and relates to the technical field of power distribution network optimization control. The island division method comprises the following steps: calculating to obtain an island formation rate in a preset time period based on a preset area range and the total load demand in the preset time period and based on the distributed power supply output of the planned island in the preset time period; establishing an optimal plan island division model based on the calculation result of the island formation rate; and solving the optimal plan island division model to obtain an optimal solution of island division, and finishing island division. The invention considers practical factors such as time sequence, correlation and the like, and solves the problem more accurately. The optimal planned island range calculated by taking the improvement of the reliability of the power distribution network as a target can more effectively exert the improvement effect of the distributed power supply on the power supply reliability, and a new thought is provided for the operation and planning of the power distribution system.
Description
Technical Field
The invention relates to the technical field of power distribution network optimization control, in particular to an island division method and system for improving reliability of a power distribution network.
Background
The distributed power supply can supply power to partial loads through the island when the power distribution network breaks down, and the power supply reliability of the power distribution network is improved. Therefore, how to choose the range of the planned island is related to the improvement effect of the distributed power supply on the reliability of the power distribution network. Because the output of the distributed power supply mainly depends on renewable energy sources such as wind power, photovoltaic and the like, the output of the renewable energy sources is intermittent, and the output of the distributed power supply is also uncertain. Once the output of the distributed power supply is less than the load demand in the island mode of operation, the island cannot be formed smoothly. The island range is too small, the power supply load is small, and the improvement on the reliability is not obvious; the island range is too large, the situation that the island cannot be formed normally easily occurs, and the reliability of the power distribution network cannot be improved, so that a new technical scheme is needed to solve the problems.
Disclosure of Invention
The invention aims to: the invention provides an island division method and system for improving reliability of a power distribution network, and aims to effectively solve the problems in the prior art.
In a first aspect, an island division method for improving reliability of a power distribution network is provided, which comprises the following steps:
S1, calculating to obtain an island formation rate in a preset period based on a preset area range and total load demand in the preset period and based on distributed power supply output of a planned island in the preset period;
s2, establishing an optimal plan island division model based on the calculation result of the island formation rate;
and S3, solving the optimal plan island division model to obtain an optimal solution of island division, and finishing island division.
In a further embodiment of the first aspect, step S1 includes calculating a rate of formation of the planned island within period j：
In the method, in the process of the invention,Representing the total load demand of the planned island within period j; representing the distributed power supply output of the planned island within a period j; representing a probability of successful formation of the planned island; A probability distribution representing a difference between the output and load demands of the distributed power source;
and when the total load demand in the planned island is smaller than the distributed power supply output, the island successfully operates.
In a further embodiment of the first aspect, step S1 further comprises for each period j an island formation rateAveraging to obtain island formation rate in a long period:
In the method, in the process of the invention, Representing island formation rate over a long period of time; Representing the number of divided time intervals.
In a further embodiment of the first aspect, step S2 further comprises:
S2-1, island formation rate in a long period of time Respectively calculating to obtain node repair-switching interruption fault timeAnd node switch interrupt failure time；
S2-2, integrating the node repair-switch interrupt failure timeAnd node switch interrupt failure timeObtaining the average fault time of the node；
S2-3, based on the average failure time of the nodeAnd obtaining an electric quantity deficiency index ENSI, taking the electric quantity deficiency index ENSI as an objective function, enabling the island range with the minimum objective function to be the required optimal planning island range, and establishing an optimal planning island division model.
In a further embodiment of the first aspect, the island formation rate is based on a long period of timeCalculating to obtain node repair-switching interruption fault time：
Based on island formation rate over a long period of timeCalculating to obtain node switching interruption fault time：
In the method, in the process of the invention,Representing virtual power flowing from node i to node j on branch ij in the virtual network; representing a collection of branches; representing virtual power flowing from node j to node i on branch ij in the virtual network; Representing the duration of the repair-switch interruption due to the branch fault; Representing the duration of the switching interruption due to the failure of branch ij; Representing the failure rate of the branch ij; indicating whether node s is within a planned island after network reconfiguration, Indicating that the node is within an island of the island,Indicating that the node is not within an island; Indicating whether the line ij is within the planned island, Indicating that the line is within an island of land,Indicating that the line is not within an island; Representing a set of load nodes.
In a further embodiment of the first aspect, the node repair-switch interrupt failure time is integratedAnd node switch interrupt failure timeObtaining the average fault time of the node：
In the method, in the process of the invention,Representing a set of load nodes.
In a further embodiment of the first aspect, the average time to failure of the node is based onObtaining an electric quantity deficiency index ENSI, taking the electric quantity deficiency index ENSI as an objective function, and enabling the island range with the minimum objective function to be the required optimal planned island range:
In the method, in the process of the invention, The average load of the node s is shown.
In a further embodiment of the first aspect, step S3 is performed when island division is performed, in case both the distribution network line and the load node are provided with switching means:
the circuit for supplying power to the load node is closed, the switch of the load node is opened, and the load node is not supplied with power;
The load node being powered indicates that the line supplying power to the load node is closed;
Step S3, solving the optimal planned island division model by adopting a genetic algorithm, and describing the range of the planned island by using whether each load node switch is closed or not, namely, using particles in the genetic algorithm as 0-1 variables which symbolize whether each load node switch is closed or not, wherein the number of particle dimensions is equal to the number of load nodes;
and the fitness value in the genetic algorithm is the objective function of the optimal plan island.
In a further embodiment of the first aspect, solving the optimal planned island division model using a genetic algorithm includes:
S3-1, m individuals form a group in an S-dimensional target search space, wherein the i-th individual represents an S-dimensional vector ；
S3-2, vectorSubstituting the objective function and recording the optimal position currently searched by the ith individual asThe optimal position currently searched by the whole group is；
S3-3, solving the minimum value of the objective function, and expressing the current optimal position of the individual i as follows:
In the method, in the process of the invention, Is an objective function; representing the optimal position searched by the ith individual in the period t; Representing the optimal position searched by the ith individual in the period t+1; Representing the location of the ith individual during period t+1;
s3-4, the current optimal position of the individual i indicates that the electric quantity deficiency index obtained by the constructed planned island is the smallest, and the current optimal position is used as an optimal solution of island division to finish island division.
As a second aspect of the present invention, an island division system for improving reliability of a power distribution network is provided, where the island division system may implement an island division method for improving reliability of a power distribution network as disclosed in the first aspect and further embodiments thereof. Specifically, the island division system comprises three components of a first calculation unit, a division model construction unit and a second calculation unit. The first calculation unit calculates an island formation rate in a predetermined period based on a predetermined area range, a total load demand in the predetermined period, and a distributed power supply output of the planned island in the predetermined period. And the division model construction unit establishes an optimal plan island division model based on the calculation result of the island formation rate. The second calculation unit is used for solving the optimal plan island division model to obtain an optimal solution of island division and finish island division.
The beneficial effects are that: the island division and system for improving the reliability of the power distribution network is provided, and the technical scheme provided by the invention considers practical factors such as time sequence, correlation and the like, so that the solution is more accurate. The optimal planned island range calculated by taking the improvement of the reliability of the power distribution network as a target can more effectively exert the improvement effect of the distributed power supply on the power supply reliability, and a new thought is provided for the operation and planning of the power distribution system.
Drawings
FIG. 1 is a schematic flow chart of the method of the present invention.
FIG. 2 is a flowchart of island division based on genetic algorithm in the present invention.
Fig. 3 is a diagram of the power grid structure adopted in the present embodiment.
Fig. 4 is a annual load demand timing curve of the power grid structure employed in the present embodiment.
Fig. 5 is a graph of annual distributed power output time sequence of the power grid structure employed in the present embodiment.
Fig. 6 is a graph of load demand and distributed power output using a scenario in this embodiment.
Fig. 7 shows the range of island planning at one occasion in this embodiment.
Fig. 8 shows the range of planned islanding under scenario two in this embodiment.
Fig. 9 shows the range of planned islanding under scenario three in this embodiment.
Fig. 10 shows the range of planned islanding under scenario four in this embodiment.
Fig. 11 shows the range of planned islanding under scene five in this embodiment.
Fig. 12 is a graph showing a correspondence relationship between island formation rate and a system power shortage index in the present embodiment.
Fig. 13 is an optimal planned island iterative fitness curve in this embodiment.
Fig. 14 shows the optimal planned island range obtained in the present embodiment.
Fig. 15 is a schematic diagram of the island division system facing to the improvement of the reliability of the power distribution network in this embodiment.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the invention may be practiced without one or more of these details. In other instances, well-known features have not been described in detail in order to avoid obscuring the invention.
As shown in fig. 1, the invention provides an island division method for improving the reliability of a power distribution network, which comprises the following steps:
And step S1, calculating to obtain the island formation rate in the preset time period based on the preset area range and the total load demand in the preset time period and based on the distributed power supply output of the planned island in the preset time period.
The embodiment discloses a method for calculating island formation rate based on a discrete convolution expression, which comprises the following steps:
the discrete convolution based on the copula function, which is built to consider the correlation, is:
discrete form of convolution:
In the method, in the process of the invention, AndRespectively isAndUpper and lower limits of (2);、 And Respectively probability distribution functions、AndIn discrete approximation of step size of。
Assume thatIs thatAndIs a cumulative distribution function (Cumulative Distribution Function, CDF) of (a), which can be expressed as a copula function:
In the method, in the process of the invention, 、Respectively representAndIs a function of the edge distribution of (a); And For correlation of (C)And (3) representing.
The discrete convolution complete formula taking into account the correlation can be expressed as:
based on the above expression of discrete convolution, the formation rate of the planned island in the period j can be obtained ：
In the method, in the process of the invention,Representing the total load demand of the planned island within period j; Representing the distributed power supply output of the planned island over period j.
And when the total load demand in the planned island is smaller than the distributed power supply output, the island successfully operates.
Island formation rate for each period jAveraging to obtain island formation rate in a long period:
In the method, in the process of the invention, Representing island formation rate over a long period of time; Representing the number of divided time intervals.
Step S2, based on the calculation result of the island formation rate, an optimal plan island division model is established, and the method specifically comprises the following steps:
first, based on island formation rate over a long period of time Respectively calculating to obtain node repair-switching interruption fault timeAnd node switch interrupt failure time；
Wherein node repair-switch interrupt failure timeThe calculation mode of (2) is as follows:
Node switch interrupt failure time The calculation mode of (2) is as follows:
In the method, in the process of the invention, Representing virtual power flowing from node i to node j on branch ij in the virtual network; representing a collection of branches; representing virtual power flowing from node j to node i on branch ij in the virtual network; Representing the duration of the repair-switch interruption due to the branch fault; Representing the duration of the switching interruption due to the failure of branch ij; Representing the failure rate of the branch ij; indicating whether node s is within a planned island after network reconfiguration, Indicating that the node is within an island of the island,Indicating that the node is not within an island; Indicating whether the line ij is within the planned island, Indicating that the line is within an island of land,Indicating that the line is not within an island; Representing a set of load nodes.
Then, integrating the node repair-switch interrupt failure timesAnd node switch interrupt failure timeObtaining the average fault time of the node：
In the method, in the process of the invention,Representing a set of load nodes.
Finally, based on the average failure time of the nodeObtaining an electric quantity deficiency index ENSI, taking the electric quantity deficiency index ENSI as an objective function, and enabling the island range with the minimum objective function to be the required optimal planned island range:
In the method, in the process of the invention, The average load of the node s is shown.
And step S3, solving the optimal plan island division model established in the step S2 to obtain an optimal solution of island division, and finishing island division.
The optimal planning island model is a complex nonlinear model and is difficult to solve by a general analysis method, so that a genetic algorithm (Genetic Algorithm, GA) can be adopted to determine an optimal solution through a large number of iterative optimization.
The present example discloses a specific procedure for solving using a genetic algorithm (Genetic Algorithm, GA):
in an S-dimensional target search space, m individuals form a group, wherein the ith individual represents an S-dimensional vector The location of each individual is likely to be the location of the solution. By combiningThe fitness of the target function can be calculated by substituting the target function, and the quality of the solution can be measured according to the fitness. The optimal position currently searched by the ith individual is recorded asThe optimal position currently searched by the whole group is. Assume thatAs an objective function, the current optimal position of the individual i can be expressed as:
and after the individuals are determined to be optimal, taking the position with optimal historical fitness in all the individuals as a global optimal position.
In the case where both the distribution network lines and the load nodes are provided with switching means, the switches of the load nodes may be opened while the lines supplying power to the nodes are closed, and the load may not be supplied, but the supply of power to the load nodes means that the lines supplying power to the nodes must be closed. In the optimal planned island division based on genetic algorithm, the scope of the planned island can be described by whether each load node switch is closed, i.e. the particles in the GA are 0-1 variables symbolizing whether each load node switch is closed, the particle dimension is equal to the number of load nodes. The fitness value in the GA is the objective function of the optimal plan island. The smaller the electric quantity deficiency index obtained by the planned island constructed by the particles is, the better the position of the particles is, and the island range with the minimum objective function is the required optimal planned island division scheme.
Optimal planning island division flow chart based on intelligent algorithm is shown in fig. 2. Based on the above scheme, the embodiment applies and analyzes the method, and specifically comprises the following steps:
In this embodiment, an IEEE 33 node test system is adopted, as shown in fig. 3, solid black circles in fig. 3 represent each node, and black numbers above the solid black circles represent node numbers; the lines formed between every two nodes are represented by grey scale numbers. The node 1 is a transformer substation node, and the rest are load nodes. Isolation switches are arranged on all the lines, and circuit breakers are arranged on the lines 1-2. The reference power of the system is 1kVA, and the reference voltage is 13.2kV. Table 1 shows data for each line, including the length of the line, the line switching failure duration, and the line repair-switching failure duration, assuming that all line failure rates are 0.1 times/(year km). The distributed power supply and the energy storage are arranged at the 14 nodes, so that the failure of the switch is not considered and the hundred percent work of the switch is ensured. The annual load demand and distributed power output are shown in figures 4 and 5.
TABLE 1 IEEE 33 node System line parameters
To verify the effectiveness of the present invention, 4 scenarios were arbitrarily chosen, all containing load demand and distributed power output over 5 hours. Fig. 6 illustrates these four scenarios. The island formation rate calculation method and the existing method provided by the invention are applied to the four scenes, and table 2 lists the island formation rates solved by the two methods.
TABLE 2 island formation Rate in each scene
| IPLP scene | The method presented herein | Existing methods |
| Scene one | 0.6711 | 0.6797 |
| Scene two | 0.7328 | 0.7188 |
| Scene three | 0.1317 | 0.1232 |
| Scene four | 0.4139 | 0.3179 |
As can be seen from fig. 6 and table 2, the method provided by the invention combines the volatility and randomness of the two, and considers the relevance of the output of the method, so that the result is more accurate in practical application.
In order to more intuitively see the influence of the planned island range on the reliability index, the planned island ranges in five scenes are randomly selected. Fig. 7 to 11 show the ranges of planned islets in five scenes, respectively, with the black solid dots in fig. 7 to 11 representing load nodes not included in the islets, and the black numerals above the nodes representing the node numbers; the black solid points are provided with dotted line excircles to represent load nodes in the island; the lines formed between every two nodes are represented by grey scale numbers. Island formation rate and various system reliability indexes under various scenes are calculated, and related results are shown in table 3.
Fig. 12 shows the relationship between the planned island formation rate and the electric quantity deficiency index. Fig. 13 is an optimal plan island division iteration result calculated based on the algorithm flow of fig. 2, and fig. 14 is a calculated optimal plan island range. In fig. 14, the solid black dots indicate load nodes not included in the island, and the black numerals above the nodes indicate node numbers; the black solid points are provided with dotted line excircles to represent load nodes in the island; the lines formed between every two nodes are represented by grey scale numbers.
TABLE 3 island formation Rate and System reliability index in each scene
| Scene one | Scene two | Scene three | Scene four | Scene five | |
| IPLP | 0.1719 | 0.1906 | 0.2625 | 0.2939 | 0.3308 |
| SAIFI (times/year) | 5.17 | 5.17 | 5.17 | 5.17 | 5.17 |
| SAIDI (h/year) | 3.406 | 3.516 | 3.386 | 3.505 | 3.429 |
| ASAI(%) | 99.9611% | 99.9599% | 99.9613% | 99.9600% | 99.9609% |
| ENSI (MWh/year) | 21.079 | 21.792 | 21.070 | 21.749 | 21.111 |
As can be seen from table 3 and fig. 12, the system reliability index is related to the island formation rate, the number of loads in the island, the degree of load dispersion, and the like, so that the range of the selected planned island is difficult to solve by adopting an analytical model, and the effectiveness of the method provided by the invention is verified.
As a preferred embodiment, an island division system 500 for improving reliability of a power distribution network is also proposed, see fig. 15. The island division system 500 may implement the island division method for improving the reliability of the power distribution network as disclosed in the above embodiment. Specifically, the island division system 500 includes three components of a first calculation unit 501, a division model construction unit 502, and a second calculation unit 503. The first calculation unit 501 calculates an island formation rate in a predetermined period based on a predetermined area range, a total load demand in the predetermined period, and based on distributed power output of the planned island in the predetermined period. The partition model construction unit 502 establishes an optimal planned island partition model based on the calculation result of the island formation rate. The second calculating unit 503 is configured to solve the optimal planned island division model, obtain an optimal solution of island division, and complete island division.
As a preferred embodiment, a computer readable storage medium is further provided, where at least one executable instruction is stored in the storage medium, where the executable instruction when executed on an electronic device causes the electronic device to perform the operation of the island division method for improving reliability of a power distribution network according to the above embodiment.
More specific examples of the computer readable storage medium in the present disclosure may include, but are not limited to: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. The computer readable storage medium may include a data signal propagated in baseband or as part of a carrier wave, with readable program code embodied therein. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination of the foregoing. A readable signal medium may also be any readable medium that is not a readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.
As described above, although the present invention has been shown and described with reference to certain preferred embodiments, it is not to be construed as limiting the invention itself. Various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (9)
1. The island division method for improving the reliability of the power distribution network is characterized by comprising the following steps of:
S1, calculating the island formation rate in a preset period based on a preset area range and the total load demand in a preset period and based on the distributed power supply output of a planned island in the preset period, and firstly calculating the formation rate of the planned island in a period j Island formation rate/>, then for each period jAveraging to obtain island formation rate/>；
S2, establishing an optimal plan island division model based on the calculation result of the island formation rate;
S2-1, island formation rate in a long period of time Respectively calculating to obtain node repair-switching interruption fault timeAnd node switch interrupt failure time/>；
S2-2, integrating the node repair-switch interrupt failure timeAnd node switch interrupt failure time/>Obtaining the average failure time/>, of the nodes；
S2-3, based on the average failure time of the nodeObtaining an electric quantity deficiency index ENSI, taking the electric quantity deficiency index ENSI as an objective function, enabling an island range with the minimum objective function to be the required optimal planning island range, and establishing an optimal planning island division model;
and S3, solving the optimal plan island division model to obtain an optimal solution of island division, and finishing island division.
2. The island division method for improving reliability of power distribution network according to claim 1, wherein the calculation plan island formation rate in period jThe expression is as follows:
；
In the method, in the process of the invention, Representing the total load demand of the planned island within period j; /(I)Representing the distributed power supply output of the planned island within a period j; /(I)Representing a probability of successful formation of the planned island; /(I)A probability distribution representing a difference between the output and load demands of the distributed power source;
and when the total load demand in the planned island is smaller than the distributed power supply output, the island successfully operates.
3. The island division method for improving reliability of power distribution network according to claim 2, wherein the island formation rate for each period jAveraging to obtain island formation rate in a long period of time, wherein the expression is as follows:
；
In the method, in the process of the invention, Representing island formation rate over a long period of time; /(I)Representing the number of divided time intervals.
4. The island division method for improving reliability of power distribution network according to claim 1, wherein island formation rate is based on a long period of timeCalculating to obtain node repair-switching interruption fault time/>：
；
Based on island formation rate over a long period of timeCalculating to obtain the node switching interruption fault time/>：
；
In the method, in the process of the invention,Representing virtual power flowing from node i to node j on branch ij in the virtual network; /(I)Representing a collection of branches; Representing virtual power flowing from node j to node i on branch ij in the virtual network; /(I) Representing the duration of the repair-switch interruption due to the branch fault; /(I)Representing the duration of the switching interruption due to the failure of branch ij; /(I)Representing the failure rate of the branch ij; /(I)Indicating whether node s is within a planned island after network reconfiguration,/>Indicating that the node is within an island of the island,Indicating that the node is not within an island; /(I)Indicating whether line ij is within the planned island,/>Indicating that the line is within an island of land,Indicating that the line is not within an island; /(I)Representing a set of load nodes.
5. Island division method for power distribution network reliability promotion according to claim 1, characterized by integrating the node repair-switch interruption failure timeAnd node switch interrupt failure time/>Obtaining the average failure time/>, of the nodes：
；
In the method, in the process of the invention,Representing a set of load nodes.
6. The island division method for improving reliability of power distribution network according to claim 5, wherein the average failure time of the nodes is based onObtaining an electric quantity deficiency index ENSI, taking the electric quantity deficiency index ENSI as an objective function, and enabling the island range with the minimum objective function to be the required optimal planned island range:
；
In the method, in the process of the invention, The average load of the node s is shown.
7. The island division method for improving reliability of a power distribution network according to claim 6, wherein in step S3, when island division is performed, in a case where a switching device is installed in both a power distribution network line and a load node:
the circuit for supplying power to the load node is closed, the switch of the load node is opened, and the load node is not supplied with power;
The load node being powered indicates that the line supplying power to the load node is closed;
Step S3, solving the optimal planned island division model by adopting a genetic algorithm, and describing the range of the planned island by using whether each load node switch is closed or not, namely, using particles in the genetic algorithm as 0-1 variables which symbolize whether each load node switch is closed or not, wherein the number of particle dimensions is equal to the number of load nodes;
and the fitness value in the genetic algorithm is the objective function of the optimal plan island.
8. The island division method for improving reliability of a power distribution network according to claim 7, wherein solving the optimal planned island division model by adopting a genetic algorithm comprises:
S3-1, m individuals form a group in an S-dimensional target search space, wherein the i-th individual represents an S-dimensional vector ；
S3-2, vectorSubstituting the objective function and recording the optimal position currently searched by the ith individual asThe optimal position currently searched by the whole group is/>；
S3-3, solving the minimum value of the objective function, and expressing the current optimal position of the individual i as follows:
；
In the method, in the process of the invention, Is an objective function; /(I)Representing the optimal position searched by the ith individual in the period t; /(I)Representing the optimal position searched by the ith individual in the period t+1; /(I)Representing the location of the ith individual during period t+1;
s3-4, the current optimal position of the individual i indicates that the electric quantity deficiency index obtained by the constructed planned island is the smallest, and the current optimal position is used as an optimal solution of island division to finish island division.
9. Island division system towards distribution network reliability promotion, characterized by includes:
The island formation rate in the preset time period is calculated based on the preset area range and the total load demand in the preset time period and on the distributed power supply output of the planned island in the preset time period, the island formation rate of the planned island in the time period j is calculated first, and then the island formation rate of each time period j is averaged to obtain the island formation rate in a long time period;
the division model construction unit is used for establishing an optimal plan island division model based on the calculation result of the island formation rate, and specifically comprises the following steps:
Based on the island formation rate in a long time period, respectively calculating to obtain node repair-switching interruption fault time and node switching interruption fault time;
integrating the node repair-switching interruption fault time and the node switching interruption fault time to obtain the average fault time of the node;
Based on the average fault time of the nodes, obtaining an electric quantity deficiency index, taking the electric quantity deficiency index as an objective function, enabling an island range with the minimum objective function to be the required optimal planning island range, and establishing an optimal planning island division model;
the second calculation unit is used for solving the optimal plan island division model to obtain an optimal solution of island division and finish island division;
The island division system is used for realizing the island division method facing to the improvement of the reliability of the power distribution network according to any one of claims 1 to 8.
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| CN108206540A (en) * | 2018-01-24 | 2018-06-26 | 天津大学 | Consider the active power distribution network isolated island division methods in important load continuous working period |
| CN112910000A (en) * | 2021-02-03 | 2021-06-04 | 国网福建省电力有限公司宁德供电公司 | Dynamic island division method for power distribution network comprising distributed power supply |
| CN116505579A (en) * | 2023-05-24 | 2023-07-28 | 国网湖北省电力有限公司电力科学研究院 | Method for micro-grid island division and active support power distribution network power restoration under fault state |
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| CN108206540A (en) * | 2018-01-24 | 2018-06-26 | 天津大学 | Consider the active power distribution network isolated island division methods in important load continuous working period |
| CN112910000A (en) * | 2021-02-03 | 2021-06-04 | 国网福建省电力有限公司宁德供电公司 | Dynamic island division method for power distribution network comprising distributed power supply |
| CN116505579A (en) * | 2023-05-24 | 2023-07-28 | 国网湖北省电力有限公司电力科学研究院 | Method for micro-grid island division and active support power distribution network power restoration under fault state |
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