Transfer scheme optimization method based on topology and line loss optimization
By adopting the preferred method of transfer scheme based on topology and line loss optimization in the distribution network, the problem that traditional transfer schemes cannot quickly determine the large amount of transfer demand in the area is solved, and a lower feeder load rate and line loss rate are achieved , improves the stability and operating status of the distribution network.
Patent Information
- Application Number
- CN202411452285.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-17
- Publication Date
- 2025-02-11
AI Technical Summary
In the distribution network, traditional transfer schemes are mainly suitable for local temporary transfer operations, and the best solution for large-scale transfer demands in the area cannot be quickly determined, resulting in low efficiency in the transfer operation and poor operating conditions of the distribution network.
The preferred method of transfer solution based on topology and line loss optimization is adopted. By analyzing the feeder of the distribution network, the feeder loss data is generated, the topology network is established, the search switch section is traversed, and the transfer solution is optimized to ensure the feeder loss rate, load peak value and The power supply radius meets the constraints.
In the presence of multiple feeder transfer and multiple transfer solutions, it is realized that the optimal transfer solution combination is determined, the feeder load rate and line loss rate are reduced, and the stability and operating state after transfer of distribution network are improved.
Smart Images
Figure CN119419749A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of power distribution network transfer planning, and in particular relates to a method for optimizing a power transfer scheme based on topology and line loss optimization. Background Art
[0002] Transfer (distribution network load transfer) is a technical solution for load redistribution or temporary allocation in the process of distribution network planning and management, which is used to improve the power supply capacity of the distribution network, meet the power load of different power customers, and facilitate regional maintenance and construction needs. In the process of distribution network planning and design, different feeders usually have a certain load margin according to the development and demand of regional power load. At the same time, the difference in power load in different feeder areas in different time periods allows the regional feeder load to be transferred to adjacent feeders without affecting the normal operation of the distribution network as a whole. Due to the large number of distribution network feeders and the complex distribution of power nodes and user nodes, it is necessary to judge several possible feeder transfer schemes in the actual operation process. The traditional scheme is mainly based on the real-time analysis and judgment of the power supply and distribution data of the feeder to be transferred and its adjacent feeders stored in the distribution information of the substation area, but the scheme is only applicable to temporary local transfer operations. When faced with a large number of transfer demands in the region, it is often impossible to quickly determine the transfer scheme. Summary of the invention
[0003] The purpose of the present invention is to provide a method for determining and optimizing a specific power transfer scheme based on topology and line loss optimization, which is used to optimize the load distribution of the distribution network and reduce the peak power load.
[0004] To achieve the above purpose, the present invention adopts the following technical solution.
[0005] A method for optimizing a power transfer scheme based on topology and line loss optimization includes the following steps:
[0006] Step 1: Analyze the distribution network feeders and generate feeder loss data; specifically include:
[0007] a1. Define power supply nodes: including power supply equipment and distribution station outgoing lines and their segments; define switch nodes: including switch function implementation equipment such as knife switches; define user nodes: including transformers; define contact nodes: including nodes with more than 1 lines connected to the tower;
[0008] a2. Initialize the distribution network topology network and extract the distribution network topology node dataset {P i}, establish user node data set {u j}, feeder data set {P i P i+1}, switch node dataset {K l};
[0009] a3. Traverse the distribution network topology network node P i+1 , if node P i+1 is a user node, then j=j+1 and the node P i+1 is added to the user node dataset {u j}; If node P i+1 If it is a contact node, then i=i+1 and add the search path to the feeder data set {P i P i+1}; If node P j If it is a switch node, then determine whether the switch node is closed. If it is closed, then i = i + 1 and add the current value of P j Search to P j+1 Line to feeder data set {P j P j+1}, if not closed, then l=l+1 and add node P j To the switch node dataset {K l};
[0010] a4. Select the feeder, call the distribution network topology network, extract the branch data, equipment operation data, and node voltage assignment data; start from the last node and calculate the line current backwards according to the load and voltage, start from the root node and use the root node voltage to calculate the node voltage forward; obtain the feeder attribute data and calculate the feeder loss;
[0011] a5. Based on a given line loss threshold, determine whether the feeder is over-damaged;
[0012] Step 2: Based on the line loss feeder data determined in step 1, a line loss feeder sequence {Fs} is generated, and the line loss feeders Fs in the line loss feeder sequence {Fs} are arranged in ascending order according to line loss;
[0013] Step 3: Perform edge switch segment analysis on each line loss feeder Fs in each line loss feeder sequence {Fs} to obtain a switch segment sequence {Ks} of each line loss feeder Fs. The switches Ks in the switch segment sequence {Ks} are arranged in descending order according to the power loss of the distribution transformer;
[0014] Step 4: Verify the validity of the power transfer scheme for feeder and switch section with line loss, including:
[0015] d1. Select the line loss feeder Fs from the line loss feeder sequence {Fs} in sequence, and extract the switch section sequence {Ks} of the line loss feeder Fs;
[0016] d2. Select the switch sections in sequence according to the switch section sequence {Ks}, input the transfer plan, traverse the original switch section range of the line, and obtain the switch section range of the incoming and outgoing lines by switching the switch sections on and off; complete the union subset calculation of the switch sections after the transfer according to the transfer plan, and perform a device union subset processing; calculate the feeder line loss after the transfer and verify the validity of the feeder after the transfer. If the verification is passed, the switch section transfer plan validity information is recorded, otherwise the transfer plan failure information is recorded;
[0017] Generate the maximum transfer range of the switch section of the feeder Fs with line loss based on the transfer plan;
[0018] d3. Constraints for load transfer within the switch section after the transfer of the line loss feeder Fs within the maximum transfer range: The constraints include: the line loss rate of the feeder after the transfer does not exceed the line loss rate of the feeder before the transfer; the load peak of the feeder after the transfer does not exceed the load peak of the feeder before the transfer; the power supply radius of the feeder after the transfer is not less than the power supply radius of the feeder before the transfer;
[0019] d4. Determine whether the feeder meets the constraint conditions after the power transfer. If it does, record the power transfer success. If not, check whether all the switch sections in the switch section list Ks have been searched. If not, return to step d2. After all the switch sections in the switch section list Ks have been searched, go to step d5.
[0020] d5, check whether all feeders in the feeder set Fs have been searched. If not, go to step d1. If all have been searched, generate a verified and successful effective power transfer plan and go to step 5;
[0021] Step 5: Based on the generated effective power transfer scheme results, generate different power transfer schemes and implement the feeder set Fs combination, and calculate the power transfer margin Sp of each feeder set ij , according to the feeder set Fs transfer margin Sp ij Sort by order from largest to smallest to generate the optimal sequence of power transfer plans.
[0022] A further improvement or preferred implementation method of the aforementioned power transfer scheme optimization method based on topology and line loss optimization, wherein step 2 also includes performing parameter integrity check on the line loss feeder Fs in the line loss feeder sequence {Fs}, wherein the content of the integrity check includes line topology path integrity check, line power distribution data parameter integrity check, and feeder effective length check; after deleting the feeders that fail the integrity check from the line loss feeder sequence {Fs}, the line loss feeder sequence {Fs} is updated.
[0023] For further improvement or preferred implementation of the aforementioned method for optimizing the power transfer scheme based on topology and line loss optimization, the specific verification contents of the validity verification in step d2 include: calculating the feeder distribution data based on the line and measurement information, and analyzing the validity of the basic power data of the feeder after the power transfer; and analyzing the validity of the line power supply range based on the feeder topology structure after the power transfer.
[0024] Its beneficial effects are:
[0025] The preferred method for power transfer scheme based on topology and line loss optimization of the present application proposes to simplify and establish topology network power supply and distribution nodes and feeders, and optimize the power transfer schemes of different switch sections in each feeder by traversing the search loop, and realize the overall optimization of the regional distribution network by optimizing the combination of power transfer schemes in a multi-feeder network. It can determine the best power transfer scheme combination based on lower feeder load rate, lower line loss rate, larger power transfer range and other goals when designing multiple feeder power transfers and multiple power transfer schemes exist, so as to ensure that better distribution network properties can be obtained after the power transfer scheme is implemented, improve the stability of the distribution network after power transfer, and optimize the operation status of the distribution network. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 It is a flow chart of a method for optimizing a power transfer scheme based on topology and line loss optimization; DETAILED DESCRIPTION
[0027] The present invention is described in detail below in conjunction with specific embodiments.
[0028] The present application relates to a method for optimizing a power transfer scheme based on topology and line loss optimization. Its main purpose is to solve the problems of difficulty in planning power transfer schemes for distribution networks caused by the increasingly complex topological structure of distribution networks and the increasing number of distribution equipment, low power transfer operation efficiency, insufficient analysis of the overall effect of power transfer schemes in the entire distribution network area, and poor linkage of power transfer schemes for distribution networks in the region. It provides an optimization approach for the selection and configuration of power transfer schemes for distribution network areas of different levels and types, thereby improving the post-power transfer performance of distribution networks in the region.
[0029] The basic process of the optimal method for power transfer scheme based on topology and line loss optimization in this application is as follows: Figure 1 As shown, it mainly includes the following steps:
[0030] Step 1: Analyze the distribution network feeders and generate feeder loss data;
[0031] Step 1 is used to establish a constant data network based on the current distribution network topology data, and to sort out nodes with clear and fixed attributes to facilitate rapid processing in the subsequent traversal search process. The execution of the transfer plan requires the use of the action of the switch node, and the action of the switch node will directly lead to changes in the distribution network topology and load distribution after the transfer. The specific contents of step 1 include:
[0032] a1. Define power supply nodes: including power supply equipment and distribution station outgoing lines and their segments; define switch nodes: including switch function implementation equipment such as knife switches; define user nodes: including transformers; define contact nodes: including nodes with more than 1 lines connected to the tower;
[0033] a2. Initialize the distribution network topology network and extract the distribution network topology node dataset {P i}, establish user node data set {u j}, feeder data set {P i P i+1}, switch node dataset {K l};
[0034] a3. Traverse the distribution network topology network node P i+1 , if node P i+1 is a user node, then j=j+1 and the node P i+1 is added to the user node dataset {u j}; If node P i+1 If it is a contact node, then i=i+1 and add the search path to the feeder data set {P i P i+1}; If node P j If it is a switch node, then determine whether the switch node is closed. If it is closed, then i = i + 1 and add the current value of P j Search to P j+1 Line to feeder data set {P j P j+1}, if not closed, then l=l+1 and add node P j To the switch node dataset {K l};
[0035] a4. Select the feeder, call the distribution network topology network, extract the branch data, equipment operation data, and node voltage assignment data; start from the last node and calculate the line current backwards according to the load and voltage, start from the root node and use the root node voltage to calculate the node voltage forward; obtain the feeder attribute data and calculate the feeder loss;
[0036] In this application, line loss refers to the power loss caused by the energy loss process such as heat generated by the current flowing through the impedance during the operation of the feeder and the equipment on the line. The feeder loss includes the sum of the line losses generated by all nodes or equipment from the initial point to the end of the line; its expression is ΔW = Q S -Q C ;Q S Refers to the power supply, Q C It refers to the effective amount of electricity;
[0037] In the actual calculation process, different feeder types, equipment and specific nodes have corresponding line loss calculation methods, which should be calculated and processed according to the corresponding standards of the distribution network.
[0038] a5. Based on a given line loss threshold, determine whether the feeder is over-damaged;
[0039] Step 2: Based on the line loss feeder data determined in step 1, a line loss feeder sequence {Fs} is generated, and the line loss feeders Fs in the line loss feeder sequence {Fs} are arranged in ascending order according to line loss;
[0040] This step is used to create a data set of feeder lines with excessive line losses and sort them by line loss size, so as to give priority to high-line-loss feeders, reduce local line-loss peaks, and plan power transfer plans more reasonably.
[0041] It also includes performing parameter integrity check on the line loss feeder Fs in the line loss feeder sequence {Fs}, wherein the integrity check includes line topology path integrity check, line power distribution data parameter integrity check, and feeder effective length check; and updating the line loss feeder sequence {Fs} after deleting the feeders that fail the integrity check from the line loss feeder sequence {Fs}.
[0042] Due to the close distance between adjacent switch nodes and the explicit properties of specific equipment in the distribution network, some lines or equipment structures, although in the form of feeders in the distribution network topology, are not feeders that can be used for power transfer operations. Integrity verification is used to ensure that the obtained distribution network lines are complete and valid feeders to ensure that they can be used for power transfer processing.
[0043] Step 3: Perform edge switch segment analysis on each line loss feeder Fs in each line loss feeder sequence {Fs} to obtain a switch segment sequence {Ks} of each line loss feeder Fs. The switches Ks in the switch segment sequence {Ks} are arranged in descending order according to the power loss of the distribution transformer;
[0044] Step 4: Verify the validity of the power transfer scheme for feeder and switch section with line loss
[0045] d1. Select the line loss feeder Fs from the line loss feeder sequence {Fs} in sequence, and extract the switch section sequence {Ks} of the line loss feeder Fs;
[0046] d2. Select the switch sections in sequence according to the switch section sequence {Ks}, input the transfer plan, traverse the original switch section range of the line, and obtain the switch section range of the incoming and outgoing lines by switching the switch sections on and off; complete the union subset calculation of the switch sections after the transfer according to the transfer plan, and perform a device union subset processing; calculate the feeder line loss after the transfer and verify the validity of the feeder after the transfer. If the verification is passed, the switch section transfer plan validity information is recorded, otherwise the transfer plan failure information is recorded;
[0047] The specific verification contents of the validity verification include: calculating the feeder distribution data based on the line and measurement information, analyzing the validity of the basic power data of the feeder after the transfer; and analyzing the validity of the line power supply range based on the feeder topology structure after the transfer.
[0048] Generate the maximum transfer range of the switch section of the feeder Fs with line loss based on the transfer plan;
[0049] d3. Constraints for load transfer within the switch section after the transfer of the line loss feeder Fs within the maximum transfer range: The constraints include: the line loss rate of the feeder after the transfer does not exceed the line loss rate of the feeder before the transfer; the load peak of the feeder after the transfer does not exceed the load peak of the feeder before the transfer; the power supply radius of the feeder after the transfer is not less than the power supply radius of the feeder before the transfer;
[0050] The line loss rate is an electricity indicator for considering the economic efficiency of a line. Specifically, it refers to the ratio of line loss to power supply on the line.
[0051] d4. Determine whether the feeder meets the constraint conditions after the power transfer. If it does, record the power transfer success. If not, check whether all the switch sections in the switch section list Ks have been searched. If not, return to step d2. After all the switch sections in the switch section list Ks have been searched, go to step d5.
[0052] d5, check whether all feeders in the feeder set Fs have been searched. If not, go to step d1. If all have been searched, generate a verified and successful effective power transfer plan and go to step 5;
[0053] Step 5: Based on the generated effective power transfer scheme results, generate different power transfer schemes and implement the feeder set Fs combination, and calculate the power transfer margin Sp of each feeder set ij , according to the feeder set Fs transfer margin Sp ij Sort by order from largest to smallest to generate the optimal sequence of power transfer plans.
[0054] The power transfer scheme and its combination obtained through the above steps can effectively ensure the basic properties of the local and overall distribution network after the execution of the power transfer scheme, while achieving advantages in the economic and stability indicators of the distribution network such as line loss rate and peak compliance as much as possible.
[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.
Claims
1. A method for optimizing a power transfer scheme based on topology and line loss optimization, characterized in that: The steps include: Step 1: Analyze the distribution network feeders and generate feeder loss data; specifically include: a1. Define power supply nodes: including power supply equipment and distribution station outgoing lines and their segments; define switch nodes: including switch function implementation equipment such as knife switches; define user nodes: including transformers; define contact nodes: including nodes with more than 1 lines connected to the tower; a2. Initialize the distribution network topology network and extract the distribution network topology node dataset {P i }, establish user node data set {u j }, feeder data set {P i P i+1 }, switch node dataset {K l }; a3. Traverse the distribution network topology network node P i+1 , if node P i+1 is a user node, then j=j+1 and the node P i+1 is added to the user node dataset {u j }; If node P i+1 If it is a contact node, then i=i+1 and add the search path to the feeder data set {P i P i+1 }; If node P j If it is a switch node, then determine whether the switch node is closed. If it is closed, then i = i + 1 and add the current value of P j Search to P j+1 Line to feeder data set {P j P j+1 }, if not closed, then l=l+1 and add node P j To the switch node dataset {K l }; a4. Select the feeder, call the distribution network topology network, extract the branch data, equipment operation data, and node voltage assignment data; start from the last node and calculate the line current backwards according to the load and voltage, start from the root node and use the root node voltage to calculate the node voltage forward; obtain the feeder attribute data and calculate the feeder loss; a5. Based on a given line loss threshold, determine whether the feeder is over-damaged; Step 2: Based on the line loss feeder data determined in step 1, a line loss feeder sequence {Fs} is generated, and the line loss feeders Fs in the line loss feeder sequence {Fs} are arranged in ascending order according to line loss; Step 3: Perform edge switch segment analysis on each line loss feeder Fs in each line loss feeder sequence {Fs} to obtain a switch segment sequence {Ks} of each line loss feeder Fs. The switches Ks in the switch segment sequence {Ks} are arranged in descending order according to the power loss of the distribution transformer; Step 4: Verify the validity of the power transfer scheme for feeder and switch section with line loss; specifically include: d1. Select the line loss feeder Fs from the line loss feeder sequence {Fs} in sequence, and extract the switch section sequence {Ks} of the line loss feeder Fs; d2. Select the switch sections in sequence according to the switch section sequence {Ks}, input the transfer plan, traverse the original switch section range of the line, and obtain the switch section range of the incoming and outgoing lines by switching the switch sections on and off; complete the union subset calculation of the switch sections after the transfer according to the transfer plan, and perform a device union subset processing; calculate the feeder line loss after the transfer and verify the validity of the feeder after the transfer. If the verification is passed, the switch section transfer plan validity information is recorded, otherwise the transfer plan failure information is recorded; Generate the maximum transfer range of the switch section of the feeder Fs with line loss based on the transfer plan; d3. Constraints for load transfer within the switch section after the transfer of the line loss feeder Fs within the maximum transfer range: The constraints include: the line loss rate of the feeder after the transfer does not exceed the line loss rate of the feeder before the transfer; the load peak of the feeder after the transfer does not exceed the load peak of the feeder before the transfer; the power supply radius of the feeder after the transfer is not less than the power supply radius of the feeder before the transfer; d4. Determine whether the feeder meets the constraint conditions after the power transfer. If it does, record the power transfer success. If not, check whether all the switch sections in the switch section list Ks have been searched. If not, return to step d2. After all the switch sections in the switch section list Ks have been searched, go to step d5. d5, check whether all feeders in the feeder set Fs have been searched. If not, go to step d1. If all have been searched, generate a verified and successful effective power transfer plan and go to step 5; Step 5: Based on the generated effective power transfer scheme results, generate different power transfer schemes and implement the feeder set Fs combination, and calculate the power transfer margin Sp of each feeder set ij , according to the feeder set Fs transfer margin Sp ij Sort by order from largest to smallest to generate the optimal sequence of power transfer plans.
2. According to claim 1, a method for optimizing a power transfer scheme based on topology and line loss optimization is characterized in that: The step 2 also includes performing parameter integrity check on the line loss feeder Fs in the line loss feeder sequence {Fs}, wherein the integrity check includes line topology path integrity check, line power distribution data parameter integrity check, and feeder effective length check; and updating the line loss feeder sequence {Fs} after deleting the feeders that fail the integrity check from the line loss feeder sequence {Fs}.
3. The method for optimizing a power supply transfer scheme based on topology and line loss optimization according to claim 1, characterized in that: The specific verification contents of the validity verification in step d2 include: calculating the feeder distribution data based on the line and measurement information, analyzing the validity of the basic power data of the feeder after the transfer; and analyzing the validity of the line power supply range based on the feeder topology structure after the transfer.