A method, system, device, and medium for selecting the connection location of a loop closing device.

Abstract

This invention relates to the field of power systems, specifically to a method, system, equipment, and medium for selecting the access location of a loop-closing device. The process involves generating typical daily scenarios for new energy power generation systems and loads; randomly simulating different times and line faults in the distribution network; calculating grid operation status indicators between different nodes of the distribution network where the loop-closing device is connected; constructing an indicator matrix; evaluating different loop-closing device access schemes; and forming an evaluation decision vector for loop-closing device access schemes for specific fault scenarios through standardization and maximum / minimum value analysis. The process then determines whether the number of simulations for the fault scenario is less than a preset total number of simulations. If so, the number of simulations is increased, and the grid operation status indicators are recalculated; otherwise, the process proceeds to the next step. Using evidence theory, a final access scheme for the loop-closing device, incorporating multiple indicators across multiple scenarios, is formed. This invention guides the selection of the access location for loop-closing devices, improving the reliability of power system operation and the power service capabilities of the distribution network.

Description

Technical Field

[0001] This invention relates to the field of power systems, and more specifically to a method, system, device, and medium for selecting the connection location of a loop closing device. Background Technology

[0002] As the end point of the power grid, the distribution network plays a crucial role in providing and distributing electricity to customers. With the large-scale integration of distributed generation, renewable energy, and energy storage systems into the distribution network, the complexity of multiple sources coexisting and the proactive coordination of source-grid-load-storage elements present both opportunities and challenges for ensuring power supply reliability and improving power quality. Domestic distribution networks using a "closed-loop design, open-loop operation" power supply mode, when operating in open-loop mode, cannot guarantee continuous power supply to critical users due to short-term power outages during switching operations, and cannot fully leverage the supporting role of distributed generation, renewable energy, and energy storage systems. As a key technology for power network reconfiguration, loop-connection technology is of great significance for improving the reliability and economy of distribution network power supply. However, the location of the loop-connection device has a certain impact on distribution network fault reconfiguration, proactive coordination of source-grid-load-storage applications, and system economic improvement. Currently, the planning of the loop-connection device location in the distribution network does not adequately consider factors such as the location and capacity of distributed generation, renewable energy, and energy storage systems, as well as the increasing demand for various power services. Therefore, there is an urgent need for a method, system, equipment, and medium for selecting the location of the loop-connection device. Summary of the Invention

[0003] The purpose of this invention is to provide a method, system, device, and medium for selecting the access location of a loop closing device in a distribution network, so as to solve the problem that the selection of the access location of a loop closing device in a distribution network lacks comprehensive consideration of multiple scenarios and the integration of multiple indicators.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A method for selecting the connection location of a loop closing device includes the following steps:

[0006] S1. Obtain the line parameters of the target area's distribution network and information on distributed power sources, new energy systems, energy storage systems, and loads, and generate various typical daily scenarios for new energy power generation systems and loads;

[0007] S2. In a typical daily scenario where no line fault simulation has been performed, select a typical daily scenario as the current fault simulation scenario. Based on the current fault simulation scenario, randomly simulate line faults in the distribution network at different times to form several loop-closing device access schemes. Calculate the power grid operation status indicators between different nodes of the distribution network where the loop-closing devices are connected, and construct an indicator matrix based on the power grid operation status indicators.

[0008] S3. Based on the indicator matrix, evaluate different loop closure device access schemes and form an evaluation decision vector for the loop closure device access scheme for the current fault scenario.

[0009] S4. Determine whether the number of simulations of the fault scenario is less than the preset total number of simulations. If yes, increase the number of simulations and return to step S2 to recalculate the power grid operation status indicators. If no, proceed to step S5.

[0010] S5. Utilize evidence theory to integrate evaluation decision vectors for loop-closing device access schemes across multiple fault scenarios, forming a final access scheme for loop-closing devices that integrates multiple indicators across multiple scenarios.

[0011] Optionally, step S1 includes the following steps:

[0012] S1.1 Obtain basic information on the distribution network structure, line parameters, distributed power sources, new energy power plants, and energy storage systems in the target area;

[0013] S1.2 Based on the historical data of the new energy power plants in the target area and the historical data of the user load of each node, the typical daily operating data of the new energy power plants and the user load of each node are established using the scenario generation and reduction method, and the typical daily scenario of the new energy power generation system and load is generated.

[0014] Optionally, step S2 includes the following steps:

[0015] S2.1 Based on the definition of distribution network nodes in the target area, construct access schemes for the loop closing device between two different and unconnected nodes, forming a set of access schemes for the loop closing device;

[0016] S2.2 Set the total number of fault scenario simulations, initialize the number of fault scenario simulations, and define the power grid operation status indicators used for power grid operation status evaluation after the loop closing device is connected under power grid faults.

[0017] S2.3. Combining typical daily operating data of new energy power plants and user loads at each node, random simulations of fault scenarios at different times and locations of the power grid are performed. By traversing the possible access schemes for the loop-closing devices formed in step 2.1, the structural changes of the regional power grid after the loop-closing devices are connected under fault conditions are analyzed. The output of distributed power sources, new energy power plants, energy storage systems, and user loads is optimized to minimize the load shortage rate, and the power grid operating status indicators are calculated.

[0018] S2.4 Based on the power grid operation status indicators under different loop closure device access schemes calculated in step 2.3, construct an indicator matrix for different loop closure device access schemes.

[0019] Optionally, step S2.3 includes the following steps:

[0020] Randomly simulate fault scenarios in the power grid at different times and locations along different lines;

[0021] For each loop-closing device, analyze the changes in the regional power grid structure under fault conditions.

[0022] If the regional power grid maintains a radial grid structure after being connected via a loop-closing device following a fault, then the power network parameters, such as the connection matrix and admittance matrix, are updated, and the output of distributed power sources, new energy power plants, energy storage systems, and user loads is optimized using the optimal power flow method with the minimum load shortage rate as the objective function.

[0023] In the optimal power flow calculation, a constraint condition limiting the rated capacity of the loop closing device is added;

[0024] Based on the optimization calculation results, calculate the power grid operation status indicators;

[0025] The calculated power grid operation status indicators are used to evaluate the performance of the loop-closing device access scheme.

[0026] Optionally, in step S2.3, if the regional power grid has multiple independent power grid structures connected via a loop-closing device after a fault, then the following steps are performed:

[0027] Update power network parameters for multiple independent power grids;

[0028] For each independent power grid, with the minimum load shortage rate as the objective function, the output of distributed power sources, new energy power plants, energy storage systems and user loads within the independent power grid is optimized using the optimal power flow method. At the same time, the constraint of the rated capacity limit of the loop-closing device is added to the optimal power flow calculation.

[0029] Based on the optimization calculation results of each independent power grid, the power grid operation status indicators of each independent power grid are calculated.

[0030] The same power grid operation status indicators calculated from multiple independent power grids are processed to evaluate the overall regional power grid operation status.

[0031] Optionally, step S3 includes the following steps:

[0032] S3.1 Remove the dimensions of each indicator by column, standardize the indicator matrix, and form a standardized matrix;

[0033] S3.2 Find the maximum value in each column of the standardized matrix and form a maximum value vector; find the minimum value in each column of the standardized matrix and form a minimum value vector.

[0034] S3.3. Based on the maximum value vector and the minimum value vector, evaluate the score of the loop closure device access scheme and form an evaluation decision vector for the loop closure device access scheme.

[0035] Optionally, step S5 includes:

[0036] Define an identification framework in evidence theory, taking each loop-connection device access scheme as an element in the framework;

[0037] Based on the evaluation decision vector under each fault scenario, multi-scenario fusion is performed using evidence reasoning formula combination rules.

[0038] The loop-closing device with the highest evaluation score after merging is determined as the optimal connection location for the loop-closing device in the distribution network.

[0039] A loop closing device access location selection system, comprising:

[0040] The power grid information acquisition unit is used to acquire line parameters of the distribution network in the target area and information on distributed power sources, new energy systems, energy storage systems and loads, and generate typical daily scenarios of new energy power generation systems and loads;

[0041] The power grid index calculation unit is used to calculate the power grid operation status index between different nodes of the distribution network connected to the loop closing device based on typical daily scenarios and random simulation of different times and line faults in the distribution network, and to construct an index matrix based on the power grid operation status index.

[0042] The evaluation decision vector generation unit is used to evaluate different loop closure device access schemes based on the index matrix of different loop closure device access schemes. Through standardization processing and maximum and minimum value analysis, it forms an evaluation decision vector for loop closure device access schemes for specific fault scenarios.

[0043] The fault simulation judgment unit is used to determine whether the number of fault scenario simulations is less than the preset total number of simulations;

[0044] The evaluation decision vector fusion unit is used to integrate the evaluation decision vectors of the loop-connected device access schemes for multiple fault scenarios after all fault scenario simulations are completed, using evidence theory to form the final access scheme for the loop-connected device that integrates multiple indicators under multiple scenarios.

[0045] An electronic device includes a processor and a memory, the processor being configured to execute a computer program stored in the memory to implement a method for selecting the access location of a loop-closing device.

[0046] A computer-readable storage medium storing at least one instruction that, when executed by a processor, implements a method for selecting the access location of a loop-closing device.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] 1. This invention analyzes the support capability of loop-closing devices for power service demand under different access locations by combining various distribution network fault transfer scenarios. By establishing a multi-attribute evaluation model and evaluation method, it forms an evaluation of the access location of the loop-closing device, and integrates the evaluation results of various distribution network fault transfer scenarios to form a guide for the selection of the access location of the loop-closing device, so as to improve the distribution network's ability to ensure the reliability of power system operation and power service.

[0049] 2. The method proposed in this invention can adapt to various power distribution network fault transfer scenarios and provide a more comprehensive evaluation of the power grid operation status by simulating different times and line faults.

[0050] 3. By constructing an index matrix and an evaluation decision vector, this invention not only considers a single index, but also comprehensively evaluates the performance of the loop-connected device access scheme through the fusion of multiple indices.

[0051] 4. The present invention employs a fault simulation judgment and iterative optimization method to ensure that the connection position of the loop closing device can be fully evaluated and optimized under all possible fault scenarios.

[0052] 5. This invention utilizes evidence theory to fuse evaluation decision vectors under various fault scenarios, thereby improving the accuracy and reliability of decision-making. Attached Figure Description

[0053] Figure 1 This is a schematic flowchart of an embodiment of the method for selecting the access position of a loop closing device according to the present invention.

[0054] Figure 2 This is a schematic diagram of a power network structure.

[0055] Figure 3 This is a schematic diagram illustrating the implementation process of the power grid index calculation module connected to the loop closing device of the present invention.

[0056] Figure 4 This is a schematic diagram illustrating the calculation process of power grid operation status technical indicators under different fault scenarios using different loop-closing device access schemes according to the present invention.

[0057] Figure 5 This is a schematic diagram of the location of the first type of fault in a power network structure.

[0058] Figure 6 This is a schematic diagram of the second type of fault location in a power network structure.

[0059] Figure 7 This is a structural block diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0060] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0061] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0062] This invention provides a method for selecting the access location of a loop-connected device based on the fusion of multiple indicators in multiple scenarios. Taking a regional power grid structure containing distributed power sources, new energy systems, load users, and energy storage systems as an example, the implementation process of the method in this embodiment is demonstrated.

[0063] by Figure 2 Taking the power network structure shown as an example, the figure indicates the location of distributed power sources, new energy power stations (taking photovoltaic power stations as an example), energy storage systems, and load users. The new energy power station only outputs active power and does not perform virtual inertia control. It is assumed that the loop closing device is connected between nodes 10 and 22. When a fault occurs, the loop closing device can connect the two power network nodes. After the fault is recovered, the loop closing device is deactivated, and the two power network nodes are no longer connected. This invention implements a multi-attribute decision-making method for selecting the access location of the loop closing device.

[0064] like Figure 1 As shown, a method for selecting the connection location of a loop closing device includes the following steps:

[0065] S1. Obtain the line parameters of the target area's distribution network and information on distributed power sources, new energy systems, energy storage systems, and loads, and generate various typical daily scenarios for new energy power generation systems and loads.

[0066] Specifically, the following steps are included:

[0067] S1.1 Obtain the basic information of the target area's power distribution network structure, line parameters, distributed power sources, new energy power plants, and energy storage systems; specific basic information includes: the access location, rated power, and installed capacity of distributed power sources, new energy power plants, and energy storage systems.

[0068] S1.2 Based on the historical data of the new energy power plants in the target area and the historical data of the user load of each node, the typical daily operating data of the new energy power plants and the user load of each node are established using the scenario generation and reduction method, and the typical daily scenario of the new energy power generation system and load is generated.

[0069] S2. In a typical daily scenario where no line fault simulation has been performed, select a typical daily scenario as the current fault simulation scenario. Based on the current fault simulation scenario, randomly simulate line faults in the distribution network at different times to form several loop-closing device access schemes. Calculate the power grid operation status indicators between different nodes of the distribution network where the loop-closing devices are connected, and construct an indicator matrix based on the power grid operation status indicators.

[0070] Includes the following steps:

[0071] S2.1 Based on the definition of distribution network nodes in the target area, construct access schemes for the loop closing device between two different and unconnected nodes, forming a set of access schemes for the loop closing device;

[0072] Specifically, based on the definition of distribution network nodes in the target area, an access scheme for the loop closing device between two different and unconnected nodes is constructed, forming a set of possible access schemes for the loop closing device Ω, i.e., Ω = {Sc i,j Let ,i=1,2…,Node,j=1,2…,Node}, where Sc i,j Let represent the access scheme of the loop-closing device connecting the i-th node and the j-th node, where i ≠ j and the i-th node and the j-th node are not connected in the regional distribution network described in step 1. Node represents the number of nodes in the regional distribution network. Define the set Ω of access schemes for the loop-closing device as having a total of S access schemes, that is, the set has a total of S elements, where the s-th scheme can be represented as Sc(s), s = 1, 2, ..., S;

[0073] S2.2 Set the total number of fault scenario simulations, initialize the number of fault scenario simulations, and define the power grid operation status indicators used for power grid operation status evaluation after the loop closing device is connected under power grid faults.

[0074] Specifically, the total number of fault scenario simulations is set to K, and the number of fault scenario simulations is k=1. Technical indicators for evaluating the grid operation status after the loop-closing device is connected under grid fault conditions are defined, such as grid line loss, absolute value of the maximum voltage deviation of the grid, load power shortage rate, power shortage duration, and new energy abandonment rate.

[0075] S2.3. Combining typical daily operating data of new energy power plants and user loads at each node, random simulations of fault scenarios at different times and locations of the power grid are performed. By traversing the possible access schemes for the loop-closing devices formed in step 2.1, the structural changes of the regional power grid after the loop-closing devices are connected under fault conditions are analyzed. The output of distributed power sources, new energy power plants, energy storage systems, and user loads is optimized to minimize the load shortage rate, and the power grid operating status indicators are calculated. Figure 4 The process of calculating the technical indicators of power grid operation status under different loop-closing device access schemes in different fault scenarios is demonstrated.

[0076] Specifically, the following steps are included:

[0077] Randomly simulate fault scenarios in the power grid at different times and locations along different lines;

[0078] For each loop-closing device, analyze the changes in the regional power grid structure under fault conditions.

[0079] If the regional power grid maintains a radial grid structure after being connected via a loop-closing device following a fault, then the power network parameters, such as the connection matrix and admittance matrix, are updated, and the output of distributed power sources, new energy power plants, energy storage systems, and user loads is optimized using the optimal power flow method with the minimum load shortage rate as the objective function.

[0080] In the optimal power flow calculation, a constraint condition limiting the rated capacity of the loop closing device is added;

[0081] Based on the optimization calculation results, calculate the power grid operation status indicators;

[0082] The calculated power grid operation status indicators are used to evaluate the performance of the loop-closing device access scheme.

[0083] If the regional power grid has multiple independent power grid structures connected via a loop closing device after a fault, the following steps are performed:

[0084] Update power network parameters for multiple independent power grids;

[0085] For each independent power grid, with the minimum load shortage rate as the objective function, the output of distributed power sources, new energy power plants, energy storage systems and user loads within the independent power grid is optimized using the optimal power flow method. At the same time, the constraint of the rated capacity limit of the loop-closing device is added to the optimal power flow calculation.

[0086] Based on the optimization calculation results of each independent power grid, the power grid operation status indicators of each independent power grid are calculated.

[0087] The same power grid operation status indicators calculated from multiple independent power grids are processed to evaluate the overall regional power grid operation status.

[0088] Specifically, it includes the following steps:

[0089] Step 2.3.1 Randomly simulate fault scenarios of the power grid at different times and different line locations, and let the loop closing device be connected to the scheme number s = 1;

[0090] Step 2.3.2 analyzes the changes in the regional power grid structure under the s-th loop-closing device access scheme. If the regional power grid still forms a radial power grid structure after the fault, after access via the s-th loop-closing device, then the target area distribution network fault state I is as follows: Figure 2In the power network structure shown, a line fault occurs in branch 2 to branch 9 or branch 18 to branch 21, such as... Figure 5 As shown, proceed to step 2.2.3; if, after a fault, the regional power grid can be connected via the s-th loop-closing device and there are multiple independent power grid structures, then the target area distribution network fault condition II is as follows: Figure 2 In the power network structure shown, a line fault occurs in branch 1, branch 10 to branch 17, or branch 22 to branch 24, such as... Figure 6 As shown, proceed to step 2.2.5;

[0091] Step 2.3.3: The regional power grid still exhibits a radial grid structure. Power network parameters, such as the connectivity matrix and admittance matrix, are updated. The optimal power flow method is used to optimize and calculate the output of distributed generation, new energy power plants, energy storage systems, and user loads, with the minimum load shortage rate as the objective function. Furthermore, a constraint condition limiting the rated capacity of the loop-closing device is added to the optimal power flow calculation.

[0092] Step 2.3.4 If the regional power grid exhibits a radial grid structure, calculate technical indicators for evaluating the grid's operating status based on distributed generation, renewable energy power plants, energy storage systems, and user load output, such as grid line losses, absolute value of the maximum grid voltage deviation, load shortage rate, shortage duration, and renewable energy curtailment rate. The r-th technical indicator is represented by J. r (s), r = 1, 2, ..., R, where R represents the number of technical indicators;

[0093] Step 2.3.5 The regional power grid is characterized by multiple independent power grid structures. Update the power network parameters of multiple independent power grids, such as the connection matrix and admittance matrix. For each independent power grid, use the optimal power flow method to optimize and calculate the distributed power sources, new energy power plants, energy storage systems and user load output within the independent power grid with the minimum load shortage rate as the objective function. In the optimal power flow calculation, add the constraint condition of the rated capacity limit of the loop closing device.

[0094] Step 2.3.6 If the regional power grid consists of multiple independent power grids, calculate the technical indicators of each independent power grid based on its distributed generation, renewable energy power plants, energy storage systems, and user load output. These indicators include grid line losses, the absolute value of the maximum grid voltage deviation, load shortage rate, shortage duration, and renewable energy curtailment rate. Then, process the identical indicators calculated for multiple independent power grids. For example, calculate the grid line losses of the overall regional power grid by summing the grid line losses of each independent power grid. The absolute value of the maximum grid voltage deviation of the overall regional power grid is obtained by acquiring the maximum absolute value of the maximum grid voltage deviation of each independent power grid. Calculate all technical indicators used to evaluate the power grid's operating status, where the r-th technical indicator is represented as J.r (s), r = 1, 2, ..., R, where R represents the number of technical indicators;

[0095] Step 2.3.7 Determine whether the accessible scheme number s of the loop closing device is less than the total number of accessible schemes S in the set Ω of accessible schemes of the loop closing device. If yes, then s = s + 1, and return to step 2.3.2; if no, proceed to step 2.4.

[0096] S2.4 Based on the power grid operation status indicators under different loop closure device access schemes calculated in step 2.3, construct an indicator matrix for different loop closure device access schemes.

[0097] Specifically, based on the technical indicators of different loop merging device access schemes calculated in step 2.3, an indicator matrix A for different loop merging device access schemes is constructed;

[0098]

[0099] Among them, J r (s) represents the value of the r-th technical indicator under the s-th loop-closing device access scheme, s = 1, 2, ..., S, r = 1, 2, ..., R, where S and R represent the total number of accessible schemes in the loop-closing device access scheme set Ω and the number of technical indicators after the loop-closing device is accessed under the occurrence of a grid fault, respectively.

[0100] S3. Based on the indicator matrix, evaluate different loop closure device access schemes to form an evaluation decision vector for the loop closure device access scheme in the current fault scenario.

[0101] Specifically, based on the indicator matrix of different loop merging device access schemes, different loop merging device access schemes are evaluated to form an evaluation decision vector for loop merging device access schemes for specific fault scenarios.

[0102] Step S3 includes the following steps:

[0103] S3.1 Remove the dimensions of each indicator by column, standardize the indicator matrix, and form a standardized matrix.

[0104] Specifically, the index matrix A is standardized by removing the dimensions of each indicator by column, forming a standardized matrix B, as follows:

[0105]

[0106] Among them, the value J of the r-th technical indicator under the s-th loop-closing device access scheme r (s) is the standardized value of b r (s),

[0107] S3.2 Find the maximum value in each column of the standardized matrix and form a maximum value vector. Find the minimum value in each column of the standardized matrix and form a minimum value vector.

[0108] Specifically, find the maximum value in each column of the standardized matrix B, and construct the maximum value vector b. max =[bmax 1,bmax 2,…,bmax R], where bmax r=max({b r (s)|s=1,2,..,S},r=1,2,..,R;Find the minimum value of each column in the standardized matrix B, forming the minimum value vector b min =[bmin 1,bmin 2,…,bmin R], where bmin r=min({b r (s)|s=1,2,..,S}), r=1,2,..,R.

[0109] S3.3. Based on the maximum value vector and the minimum value vector, evaluate the score of the loop closure device access scheme and form an evaluation decision vector for the loop closure device access scheme.

[0110] Specifically, based on the maximum and minimum value vectors, the scores of the loop-closing device access schemes are evaluated, forming an evaluation decision vector for the loop-closing device access schemes. The evaluation score calculation formula for the s-th loop-closing device access scheme is as follows:

[0111]

[0112] Therefore, the evaluation decision vector Score=[Score(1),Score(2),…,Score(S)] of the loop closure device access scheme can be obtained, and the evaluation result Evi under the k-th fault scenario simulation can be defined. (k) =[Evi (k) (1), Evi (k) (2),…,Evi (k) (S)], let Evi (k) =Score, where Evi is the evaluation score of the s-th loop-closing device access scheme under the k-th fault scenario simulation. (k) (s)=Score(s),s=1,2,…,S;

[0113] S4. Determine whether the number of simulations of the fault scenario is less than the preset total number of simulations. If yes, increase the number of simulations and return to step S2 to recalculate the power grid operation status indicators. If no, proceed to step S5.

[0114] Specifically, determine whether the number of fault scenario simulations is less than the set total number of fault scenario simulations. If yes, set the number of fault scenario simulations k = k + 1 and return to step 2.3; otherwise, proceed to step 5.

[0115] S5. After all fault scenario simulations are completed, the evaluation decision vectors of the loop-connected device access schemes for multiple fault scenarios are integrated using evidence theory to form the final access scheme for the loop-connected device that integrates multiple indicators under multiple scenarios.

[0116] Specifically, by using evidence theory to integrate evaluation decision vectors for loop-closing device access schemes across multiple fault scenarios, a final access scheme for loop-closing devices with multi-indicator fusion under multiple scenarios is formed.

[0117] Step S5 includes:

[0118] S5.1 Define the identification framework in evidence theory, taking each loop-connection device access scheme as an element in the framework;

[0119] Let the number of fault scenario simulations be k = 1 and the evaluation decision vector be Pr1 = Evi (k) Define the identification framework F = {Sc(1), Sc(2), ..., Sc(S)}, where Sc(s) represents the access scheme of the s-th loop closing device. (k) This represents the evaluation result of the connection scheme of S loop-closing devices under the k-th fault scenario simulation.

[0120] S5.2 Based on the evaluation decision vector under each fault scenario, use the evidence reasoning formula combination rules to perform multi-scenario fusion;

[0121] Let the number of fault scenario simulations be k = k + 1. Using the evidence reasoning formula, the evaluation decision vector Pr1 and Evi are fused. (k) The fused evaluation decision vector Pr2 is obtained.

[0122]

[0123] Where, Pr2(Sc(s)) represents the evaluation decision vector of the s-th loop-joining device access scheme after fusion, Pr1(Sc(si)) represents the evaluation decision vector of the si-th loop-joining device access scheme, and Evi (k) (Sc(sj)) represents the evaluation decision vector for the sj-th loop-closing device access scheme under the k-th fault scenario simulation, where k c The conflict coefficient is equal to

[0124] Determine if the number of fault scenario simulations k is less than or equal to the set total number of fault scenario simulations K. If yes, then Pr1 = Pr2 and return to step 5.2; otherwise, proceed to step 5.3.

[0125] S5.3 Determine the loop-closing device access scheme with the highest evaluation score after fusion, and use it as the optimal access location for the loop-closing device in the distribution network.

[0126] Specifically, using Sc(s) = arg(max(Pr2)), the loop device access scheme s represented by the maximum value of the fused evaluation decision vector Pr2 is returned as the final loop device access scheme, completing the loop device access location selection process for fusion of multiple service requirements in multiple scenarios, where arg(·) represents the loop device access scheme represented by the maximum value index.

[0127] This invention aims to overcome the current shortcomings of distribution network loop merging technology, such as the lack of design methods for selecting the access location of loop merging devices and the incomplete consideration of the comprehensive improvement capabilities of various power supply indicators during the loop merging process. This invention establishes an optimal access scheme that maximizes the comprehensive service capabilities of loop merging devices by comparing and analyzing multiple power supply indicators of different node access methods under numerous random fault simulations. By evaluating the decision vector of the loop merging device access scheme through multiple indicators, the comprehensiveness of the loop merging operation service capability can be improved. Furthermore, by combining random fault simulation concepts and decision fusion methods, the applicability of selecting the access location of loop merging devices can be enhanced.

[0128] Example 2

[0129] A loop closing device access location selection system, comprising:

[0130] The power grid information acquisition unit is used to acquire line parameters of the distribution network in the target area and information on distributed power sources, new energy systems, energy storage systems and loads, and generate typical daily scenarios of new energy power generation systems and loads;

[0131] The power grid index calculation unit is used to calculate the power grid operation status index between different nodes of the distribution network connected to the loop closing device based on typical daily scenarios and random simulation of different times and line faults in the distribution network, and to construct an index matrix based on the power grid operation status index.

[0132] The evaluation decision vector generation unit is used to evaluate different loop closure device access schemes based on the index matrix of different loop closure device access schemes. Through standardization processing and maximum and minimum value analysis, it forms an evaluation decision vector for loop closure device access schemes for specific fault scenarios.

[0133] The fault simulation judgment unit is used to determine whether the number of fault scenario simulations is less than the preset total number of simulations;

[0134] The evaluation decision vector fusion unit is used to integrate the evaluation decision vectors of the loop-connected device access schemes for multiple fault scenarios after all fault scenario simulations are completed, using evidence theory to form the final access scheme for the loop-connected device that integrates multiple indicators under multiple scenarios.

[0135] Example 3

[0136] An electronic device includes a processor and a memory, the processor being configured to execute a computer program stored in the memory to implement a method for selecting the access location of a loop-closing device.

[0137] The present invention also provides an electronic device 100 for implementing a loop-closing device access location selection method according to the above embodiments. The electronic device 100 includes a memory 101, at least one processor 102, a computer program 103 stored in the memory 101 and executable on the at least one processor 102, and at least one communication bus 104. The memory 101 can be used to store the computer program 103. The processor 102 implements the steps of the loop-closing device access location selection method of Embodiment 1 by running or executing the computer program stored in the memory 101 and calling data stored in the memory 101. The memory 101 may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created according to the use of the electronic device 100 (such as audio data), etc. Furthermore, memory 101 may include non-volatile memory, such as hard disk, RAM, plug-in hard disk, smart media card (SMC), secure digital card (SD), flash card, at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. At least one processor 102 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Processor 102 may be a microprocessor or any conventional processor, etc. Processor 102 is the control center of electronic device 100, connecting various parts of electronic device 100 via various interfaces and lines. Memory 101 in electronic device 100 stores multiple instructions to implement a loop-closing device access location selection method.

[0138] Example 4

[0139] A computer-readable storage medium storing at least one instruction that, when executed by a processor, implements a method for selecting the access location of a loop-closing device.

[0140] If the modules / units integrated in the electronic device 100 are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the implementation of all or part of the processes in the methods of the above embodiments of the present invention can also be accomplished by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, and read-only memory (ROM). Those skilled in the art should understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product implemented on one or more computer-readable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process. Figure 1 One or more processes and / or boxes Figure 1The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0141] As is known from common technical knowledge, this invention can be implemented through embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not exhaustive. All modifications within the scope of this invention or its equivalents are included in this invention.

Claims

1. A method for selecting a ring closure device access site, comprising: The method comprises the following steps: S1, obtaining the line parameters of the target area power distribution network and the information of distributed power supply, new energy system, energy storage system and load, generating typical daily scenarios of new energy power generation system and load; S2, from the typical daily scenarios without line fault simulation, a typical daily scenario is selected as the current fault simulation scenario, and the line faults of the power distribution network at different times are randomly simulated based on the current fault simulation scenario to form a plurality of loop closing device access schemes; Calculate the power grid operation state index between different nodes of the loop closing device access power distribution network, and construct an index matrix according to the power grid operation state index; S3, according to the index matrix, different loop closing device access scheme evaluation is carried out to form a loop closing device access scheme evaluation decision vector for the current fault scenario; S4, judge whether the fault scenario simulation times is less than the preset total simulation number, if yes, increase the simulation times and return to step S2 to recalculate the power grid operation state index, if not, enter step S5; S5, using evidence theory, the loop closing device access scheme evaluation decision vector of multiple fault scenarios is fused to form a loop closing device final access scheme facing multiple scenarios and multiple index fusion; The step S1 comprises the following steps: S1.1, obtaining the basic information of the target area power distribution network structure, line parameters and distributed power supply, new energy power station and energy storage system; S1.2, according to the historical data information of the target area new energy power station and the historical data information of each node user load, the typical daily operation data of new energy power station and each node user load are established by using scene generation and reduction method, and the typical daily scenarios of new energy power generation system and load are generated; The step S2 comprises the following steps: S2.1, according to the node definition of the target area power distribution network, the access scheme of the loop closing device between two different and unconnected nodes is constructed to form a loop closing device access scheme set; S2.2, set the total number of fault scenario simulation, initialize the fault scenario simulation times, and define the power grid operation state index for evaluating the power grid operation state after the loop closing device is accessed under the power grid fault; S2.3, combined with the typical daily operation data of new energy power station and each node user load, the fault scenarios of power grid at different times and different line positions are randomly simulated, the structure change of regional power grid after the loop closing device is accessed under fault is analyzed by traversing the loop closing device access scheme formed in step 2.1, the distributed power supply, new energy power station, energy storage system and user load output are optimized according to the minimum load power shortage rate, and the power grid operation state index is calculated, S2.4, according to the power grid operation state index calculated in step 2.3, the index matrix of different loop closing device access schemes is constructed.

2. The method of claim 1, wherein, Step S2.3 comprises the following steps, Randomly simulate the fault scenarios of power grid at different times and different line positions; For each loop closing device access scheme, analyze the structure change of regional power grid under fault; If the regional power grid remains a radial structure after the fault and the access of the loop-in device, the power network parameters are updated, and the optimal power flow method is used to optimize the output of the distributed power source, the new energy power station, the energy storage system, and the user load with the minimum power shortage rate of the load as the objective function; In the optimal power flow calculation, the constraint condition of the rated capacity limit of the loop-in device is added; According to the optimization calculation result, the grid operation state index is calculated; The calculated grid operation state index is used to evaluate the performance of the loop-in device access scheme.

3. The method of claim 2, wherein, In step S2.3, if there are multiple independent grid structures after the fault and the access of the loop-in device, the following steps are performed: The power network parameters of the multiple independent grids are updated; For each independent grid, the optimal power flow method is used to optimize the output of the distributed power source, the new energy power station, the energy storage system, and the user load with the minimum power shortage rate of the load as the objective function, and the constraint condition of the rated capacity limit of the loop-in device is added in the optimal power flow calculation; According to the optimization calculation result of each independent grid, the grid operation state index of each independent grid is calculated; The same grid operation state indexes calculated under the multiple independent grids are processed to evaluate the operation state of the overall regional power grid.

4. The method of claim 1, wherein, S3 step includes the following steps: S3.1, remove the dimension of each index, standardize the index matrix to form a standardized matrix; S3.2, find the maximum value of each column in the standardized matrix to form a maximum value vector, and find the minimum value of each column in the standardized matrix to form a minimum value vector; S3.3, according to the maximum value vector and the minimum value vector, the score of the loop-in device access scheme is evaluated to form an evaluation decision vector for the loop-in device access scheme.

5. The method of claim 1, wherein, Step S5 includes: Define the recognition framework in the evidence theory, and take each loop-in device access scheme as an element in the framework; According to the evaluation decision vector under each fault scene, the multi-scene fusion is performed by using the combination rule of the evidence reasoning formula; Determine the loop-in device access scheme with the highest evaluation score after fusion as the optimal access position of the loop-in device in the distribution network.

6. A system for selecting an access position of a ring closure device for implementing the method for selecting an access position of a ring closure device according to claim 1, characterized in that It includes: A grid information acquisition unit is configured to acquire line parameters of a target regional distribution network and information of distributed power sources, new energy systems, energy storage systems, and loads, and generate various typical daily scenarios of new energy power generation systems and loads; A grid index calculation unit is configured to select a typical daily scenario as a current fault simulation scenario from the typical daily scenarios without line fault simulation, simulate line faults at different times of the distribution network based on the current fault simulation scenario, and form a plurality of loop-in device access schemes; Calculate the grid operation state index between different nodes of the distribution network to which the loop-in device is accessed, and construct an index matrix according to the grid operation state index; An evaluation decision vector generation unit is configured to evaluate different loop-in device access schemes according to the index matrix, and form an evaluation decision vector of the loop-in device access scheme for the current fault scene; A fault simulation judgment unit is configured to judge whether the number of fault simulation is less than the preset total number of simulation. The evaluation decision vector fusion unit is used for fusing the evaluation decision vectors of the loop-in device access schemes of multiple fault scenes by using the evidence theory to form the final loop-in device access scheme facing the multi-scene and multi-index fusion after completing the simulation of all fault scenes.

7. An electronic device, comprising: The computer readable storage medium stores at least one instruction, and the at least one instruction is executed by the processor to implement the loop-in device access position selection method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer readable storage medium stores at least one instruction, and the at least one instruction is executed by the processor to implement the loop-in device access position selection method according to any one of claims 1 to 5.

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