Multi-segment multi-contact power distribution network fault adaptive recovery method and system based on dynamic optimization

Abstract

The invention relates to a multi-segment multi-contact power distribution network fault self-adaptive recovery method and system based on dynamic optimization. The method comprises the following steps: S1, fault primary judgment: judging whether a line has a fault or not; s2, segment merging: based on a dynamic optimization algorithm, merging the multi-segment line to a specified segment number according to the distribution transformer capacity; s3, path selection: the power distribution main station selects the longest trunk line for trial pull; s4, sequential test pull: the distribution master station remotely breaks the last section switch or outgoing line at the tail end of the line; step S5, fault re-judgment: the power distribution main station collects the terminal signal again to judge whether the fault is eliminated or not; s6, transferring and recovering power: judging whether a line fault still exists or not; and step S7, path optimization. Under the condition of limited remote control times, accurate isolation of a fault section can be adaptively completed, power supply of a non-fault section is efficiently recovered, the fault handling time is remarkably shortened, and the power failure range is narrowed.

Description

Technical Field

[0001] This invention relates to the field of power distribution automation technology, and in particular to an adaptive recovery method and system for multi-segment, multi-connection power distribution network faults based on dynamic optimization. Background Technology

[0002] Under the new circumstances, my country's power distribution network development is facing the dual goals of high-reliability power supply and intelligent transformation. With the promotion of relevant policies, the self-healing capability of the power distribution network has become a key indicator for measuring its operational level. Centralized feeder automation systems based on distribution substations serve as an important technical means to achieve self-healing, integrating terminal information, analyzing fault types, and locating faulty sections to achieve rapid fault isolation and restoration of power supply to non-faulty areas. However, existing centralized self-healing strategies have certain limitations in practical applications. Traditional methods are mainly designed for short-circuit faults, covering less than half of all faults. For more common faults such as grounding faults, open circuits, and phase loss, the system often only has fault detection capabilities but cannot achieve precise location. In such cases, manual intervention is required, involving segment-by-segment checks through methods such as testing sectional switches, leading to prolonged fault handling cycles and expanded power outage areas, thus hindering further improvement in the overall power supply reliability of the power distribution network. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide an adaptive recovery method and system for multi-segment and multi-connection distribution network faults based on dynamic optimization, which can achieve precise isolation of faulty sections and rapid restoration of power supply to non-faulty sections with a limited number of remote control operations, effectively shortening the fault handling time and reducing the scope of power outage impact.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: an adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization, comprising the following steps: Step S1, Initial Fault Judgment: The power distribution master station system collects and comprehensively analyzes the signals from various field terminals to determine whether a line fault has occurred; Step S2, Segment merging: Based on the dynamic optimization algorithm, the multi-segment lines are merged according to the transformer capacity until the preset number of segments is reached; Step S3, Path Selection: The power distribution station selects the longest main line for trial operation; Step S4, Sequential Trial: The power distribution master station remotely disconnects the last section switch at the end of the line; if no section switch meets the conditions, directly try pulling the outgoing switch and end the entire process. Step S5, Fault Reassessment: The main station system collects the terminal signal again to determine whether the fault has been eliminated; Step S6, Power Transfer and Restoration: If the line fault still exists, it indicates that the section isolated in step S2 is actually a non-faulty section. The master station then remotely closes the tie switch at the back end of the section to complete the load transfer. If there are multiple tie switches at the back end, one of them is selected for closing operation according to the preset strategy. If there is no tie point at the back end, this step is skipped. Step S7, Path optimization: If there is a better connection point between the already tested switch and the switch to be tested, then change the test path; Step S8: Repeat steps S4 to S7 until the line fault is completely eliminated.

[0005] In a preferred embodiment, in step S1, the comprehensive judgment involves the power distribution master station collecting real-time voltage and current data of the power distribution switches and transformer equipment to monitor whether they are in normal condition, thereby judging whether a fault has occurred in the line; the fault includes phase loss and grounding fault; if the voltage and current of a certain phase are both zero, it can be judged as a phase loss fault; if the voltage of a certain phase decreases while the voltages of the other two phases increase, it can be judged as a grounding fault.

[0006] In a preferred embodiment, in step S2, the segment is an independent closed circuit section defined by adjacent distribution switches.

[0007] In a preferred embodiment, in step S2, the dynamic optimization algorithm performs the following sub-steps: Step S2-1, Status Check: Determine whether the total number of segments of the current line has met the preset target; if it has, this step ends directly and the process proceeds to step S3; if it does not meet the target, proceed to step S2-2. Step S2-2, Merging Candidate Selection and Execution: Traverse all current adjacent pair combinations; for each pair of adjacent segments, calculate the sum of their respective transformer capacities; the distribution master station system will select the pair of segments with the smallest total capacity as the best merging object, execute the merging operation, and form a new, larger segment; Repeat steps S2-1 to S2-2 until the number of segments meets the requirement.

[0008] In a preferred embodiment, in step S3, the main line refers to the line from the outgoing switch of the power distribution line to each tie switch; if there are multiple tie switches in the power distribution line, then the line includes multiple main lines; if there are no tie switches in the power distribution line, then the line with the most segments is the main line.

[0009] In a preferred embodiment, in step S3, the longest trunk line specifically refers to the trunk line with the largest number of sectionalizing switches after segmentation and merging; if no sectionalizing switches are configured between the outgoing switch of the distribution line and each tie switch, the outgoing switch is directly tested and the entire process ends; if the number of sectionalizing switches is the same for multiple trunk lines, they are tested according to the switch number.

[0010] In a preferred embodiment, in step S5, the re-collection of terminal signals refers to the power distribution master station actively issuing a data collection instruction, requiring terminal equipment such as power distribution switches and transformers to upload their latest voltage and current data in real time.

[0011] In a preferred embodiment, in step S6, the tie switch refers to a switch connected to the opposite line. When closed, the load of this section can be powered by the opposite line. The preferred strategy refers to selecting the most suitable tie switch to perform the power transfer by comprehensively considering the real-time load rate of the opposite line and the importance level of the user supplied.

[0012] In a preferred embodiment, in step S7, the better connection point refers to a connection switch between the tested switch and the switch to be tested, if there is a connection switch, and the connection switch and the switch to be tested still contain a section switch, then the connection switch is considered a better connection point. With the help of such a connection point, more precise load division and transfer can be achieved, thereby reducing the power outage area. If there are multiple better connection points that meet the conditions, the test and transfer operations are performed in order from most to least number of line sections corresponding to each connection point.

[0013] This invention also provides an adaptive recovery system for multi-segment, multi-connection distribution network faults based on dynamic optimization, including a processor, a memory, and a bus. The memory stores machine-readable instructions executed by the processor. When the system is running, the processor communicates with the memory via the bus, and when the machine-readable instructions are executed by the processor, the adaptive recovery method for multi-segment, multi-connection distribution network faults based on dynamic optimization is described above.

[0014] Compared with the prior art, the present invention has the following beneficial effects: Rapid strategy execution: Based on this strategy, the power distribution master station can achieve fully automatic execution from fault identification to power restoration; and under the constraint of limited remote control times, the system can quickly and accurately locate and isolate faulty sections through intelligent optimization, while restoring power supply to non-faulty sections, minimizing fault handling time and improving the overall efficiency of power restoration.

[0015] Minimal power outage area: Traditional test pull schemes have the limitation of fixed test pull paths, often leading to unnecessary disconnection of non-faulty sections during operation. In contrast, this invention uses a dynamic optimization algorithm to evaluate and optimize the available power transfer path in real time at each test pull step. Figure 3 As shown in the case, the traditional method (pulling the power outage sequentially from back to front) would expand the power outage range to all loads between switches K2 and K3; while the strategy of this invention makes full use of multiple connection channels to precisely isolate the fault section only within the limited area enclosed by switches K2, K3 and K6, thereby achieving proactive and minimized convergence of the fault's impact range.

[0016] Load Balancing Restoration: Existing load transfer strategies often employ a "nearest transfer" model, transferring all loads to the same tie line. This can easily lead to overload on a single tie line, threatening system operational safety. This invention intelligently and evenly distributes loads outside the faulty section to multiple available tie lines during fault recovery, effectively reducing the risk of severe overload on the opposite line after transfer. While ensuring rapid power restoration for users on the faulty line, it also improves the power grid's power supply safety and economic operation. Attached Figure Description

[0017] Figure 1 The flowchart illustrates the adaptive recovery strategy for multi-segment, multi-connection distribution network faults based on dynamic optimization, according to a preferred embodiment of the present invention.

[0018] Figure 2 This paper presents a case study of a segmentation merging strategy based on a dynamic optimization algorithm.

[0019] Figure 3 This document presents an implementation case of load transfer after a failure. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0022] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application; as used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise; furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0023] An adaptive recovery strategy for faults in multi-segment, multi-tie distribution networks based on dynamic optimization, referencing Figure 1 This includes the following steps: Step S1, Initial Fault Judgment: The power distribution master station system collects and comprehensively analyzes the signals from various field terminals to determine whether a fault has occurred on the line.

[0024] Furthermore, the power distribution master station is the core control and decision-making center of the power distribution network automation system, integrating data acquisition, monitoring, analysis, management and control functions, and is the "brain" of the power distribution network.

[0025] Furthermore, in the comprehensive analysis, the power distribution master station collects real-time voltage and current data from equipment such as power distribution switches and transformers to monitor whether they are in normal condition, thereby determining whether a line fault has occurred.

[0026] Furthermore, the faults mainly include phase loss and grounding faults. Generally, if the voltage and current of a certain phase are both zero, it can be determined as a phase loss fault; if the voltage of a certain phase decreases while the voltages of the other two phases increase, it can be determined as a grounding fault.

[0027] Step S2, Segment merging: Based on the dynamic optimization algorithm, the multi-segment lines are merged according to the transformer capacity until the preset number of segments is reached.

[0028] Furthermore, the segment is an independent closed circuit section defined by adjacent distribution switches.

[0029] Furthermore, the dynamic optimization algorithm performs the following sub-steps: Step S2-1, Status Check: Determine whether the total number of segments of the current line has met the preset target. If it has, this step ends directly and the process proceeds to step S3; if it does not have, proceed to step S2-2.

[0030] Step S2-2, Merging Candidate Selection and Execution: Traverse all current adjacent pair combinations. For each pair of adjacent segments, calculate the sum of their respective transformer capacities. The system will select the pair of segments with the smallest total capacity as the optimal merging object, execute the merging operation, and form a new, larger segment.

[0031] Repeat steps S2-1 to S2-2 until the number of segments meets the requirement.

[0032] Step S3, Path Selection: The power distribution station selects the longest trunk line for trial operation.

[0033] Furthermore, the main line refers to the line from the outgoing switch of the distribution line to each tie switch; if there are multiple tie switches in the distribution line, then the line contains multiple main lines; if there are no tie switches in the distribution line, then the line with the most segments is the main line.

[0034] Furthermore, the longest trunk line specifically refers to the trunk line with the largest number of sectionalizing switches after segmentation and merging; if no sectionalizing switches are configured between the outgoing switches of the distribution line and each tie switch, the outgoing switches are directly tested and the entire process is terminated; if multiple trunk lines have the same number of sectionalizing switches, they are tested according to the switch number.

[0035] Step S4, Sequential Trial: The power distribution master station remotely disconnects the last sectionalizing switch at the end of the line; if no sectionalizing switch meets the conditions, the outgoing line switch is directly pulled, and the entire process ends.

[0036] Step S5, Fault Reassessment: The main station system collects terminal signals again to determine whether the fault has been eliminated.

[0037] Furthermore, the re-collection of terminal signals refers to the power distribution master station actively issuing a data collection command, requiring terminal equipment such as power distribution switches and transformers to upload their latest voltage and current data in real time.

[0038] Step S6, Power Transfer and Restoration: If the line fault still exists, it indicates that the section isolated in step S2 is actually a non-faulty section. The master station then remotely closes the tie switch at the back end of the section to complete the load transfer. If there are multiple tie switches at the back end, one of them is selected for closing operation according to the preset strategy. If there is no tie point at the back end, this step is skipped.

[0039] Furthermore, the connecting switch refers to a switch connected to the opposite line; when closed, the load in this section can be powered by the opposite line.

[0040] Furthermore, the preferred strategy mainly refers to selecting the most suitable tie switch to perform the power transfer by comprehensively considering factors such as the real-time load rate of the opposite line and the importance level of the users supplied. Typically, tie paths with lighter loads on the opposite line and not involving important users are preferred.

[0041] Step S7, Path Optimization: If there is a better connection point between the already tested switch and the switch to be tested, then change the test path.

[0042] Furthermore, the "better connection point" refers to a connection switch between the tested switch and the switch to be tested. If there is a connection switch between the connection switch and the switch to be tested, and the connection switch and the switch to be tested still contain a section switch, then the connection switch is considered a better connection point. With the help of such a connection point, more precise load division and transfer can be achieved, thereby reducing the power outage area. If there are multiple better connection points that meet the conditions, the test and transfer operations are carried out in order of the number of line sections corresponding to each connection point from most to least.

[0043] Repeat steps S4 to S7 until the line fault is completely eliminated.

[0044] Specific examples Figure 2 , Figure 3 As shown.

[0045] A circuit fault has occurred, located between switches K2, K3, and K6.

[0046] Step S1, Initial Fault Judgment: The power distribution master station system collects and comprehensively analyzes the signals from various field terminals to determine that there is a fault in the line.

[0047] Step S2, Segment merging: The faulty line has 7 segments. Based on the dynamic optimization algorithm, the 7 segments are merged into 5 segments according to the transformer capacity.

[0048] Step S2-1-1: The current number of segments is 7, which does not meet the set requirements. Perform the first segment merging.

[0049] Step S2-2-1: Traverse all adjacent pairs of segments, calculate the sum of transformer capacities, and find that the sum of transformer capacities of segments K3-K4 and K4-K5 is the smallest. Merge these two segments into segment K3-K5.

[0050] Step S2-1-2: The current number of segments is 6, which does not meet the set requirements, so perform the second segment merging.

[0051] Step S2-2-2: Traverse all adjacent pairs of segments, calculate the sum of transformer capacities, and find that the sum of transformer capacities of segments K6-K7-K9 and K9-K10 is the smallest. Merge these two segments into segment K6-K7-K10.

[0052] Step S2-1-3: The current number of segments is 5, which meets the set requirements. End step S2.

[0053] Step S3, Path Selection: The section between outgoing switch K1 and connecting switch K8 has the largest number of sectionalizing switches, so this path is selected for trial operation.

[0054] Step S4-1, Sequential pull: Execute operation 1 to remotely disconnect the last segment switch K7 at the end of the path.

[0055] Step S5-1, Fault Reassessment: The main station system collects terminal signals again and determines that the line still has a fault.

[0056] Step S6-1, Power Supply Restoration: If the line fault still exists, execute operation 2 to close the tie switch K8, and the load between K7 and K8 will be supplied by the opposite line.

[0057] Step S7-1, Path optimization: Although there is a connection point K10 between the tested switch K7 and the switch K6 to be tested, there is no segmented switch between K6 and K10, so K10 is not a better connection point. Continue to test along the original path.

[0058] Repeat steps S4 to S7.

[0059] Step S4-2, sequential pull: Execute operation 3 to remotely disconnect the last segment switch K6 at the end of the path.

[0060] Step S5-2, Fault Reassessment: The main station system collects terminal signals again to determine if the line still has a fault.

[0061] Step S6-2, Power Supply Restoration: If the line fault still exists, execute operation 4 to close the tie switch K7, and transfer the load between K6-K7-K10 to the opposite line for power supply.

[0062] Step S7-2, Path optimization: There is a connection point K5 between the tested switch K6 and the switch K2 to be tested, and there is a segmented switch between K5 and K2, so K5 is a better connection point, and the test path is changed.

[0063] Repeat steps S4 to S7.

[0064] Step S4-3, sequential pull: Execute operation 5 to remotely disconnect the last segment switch K3 at the end of the path.

[0065] Step S5-3, Fault Reassessment: The main station system collects terminal signals again to determine if the line still has a fault.

[0066] Step S6-3, Power Supply Restoration: If the line fault still exists, execute operation 6 to close the tie switch K5, and the load between K3 and K5 will be supplied by the opposite line.

[0067] Step S7-3, Path optimization: Although there is a connection point K6 between the tested switch K3 and the switch to be tested K2, there is no segmented switch between K2 and K6, so K6 is not a better connection point. Continue to test along the original path.

[0068] Repeat steps S4 to S7.

[0069] Step S4-4, sequential pull: Execute operation 7 to remotely disconnect the last segment switch K2 at the end of the path.

[0070] Step S5-4, Fault Reassessment: The main station system collects the terminal signal again, determines that the line fault has disappeared, and the program execution ends.

[0071] Through the above steps, the power distribution station can automatically perform isolation and power transfer operations, enabling rapid and accurate isolation of faulty sections and the transfer and restoration of power to non-faulty sections with a limited number of remote control attempts. Traditional test-operation schemes require remote control of numerous switches. The more switches tested, the more likely remote control failures are to occur, causing operational interruptions. To reduce the number of remote control attempts, this invention proposes a segmented merging strategy.

Claims

1. An adaptive recovery method for faults in a multi-segment, multi-tie distribution network based on dynamic optimization, characterized in that, Includes the following steps: Step S1, Initial Fault Judgment: The power distribution master station system collects and comprehensively analyzes the signals from various field terminals to determine whether a line fault has occurred; Step S2, Segment merging: Based on the dynamic optimization algorithm, the multi-segment lines are merged according to the transformer capacity until the preset number of segments is reached; Step S3, Path Selection: The power distribution station selects the longest main line for trial operation; Step S4, Sequential Trial: The power distribution master station remotely disconnects the last section switch at the end of the line; if no section switch meets the conditions, directly try pulling the outgoing switch and end the entire process. Step S5, Fault Reassessment: The main station system collects the terminal signal again to determine whether the fault has been eliminated; Step S6, Power Transfer and Restoration: If the line fault still exists, it indicates that the section isolated in step S2 is actually a non-faulty section. The master station then remotely closes the tie switch at the back end of the section to complete the load transfer. If there are multiple tie switches at the back end, one of them is selected for closing operation according to the preset strategy. If there is no tie point at the back end, this step is skipped. Step S7, Path optimization: If there is a better connection point between the already tested switch and the switch to be tested, then change the test path; Step S8: Repeat steps S4 to S7 until the line fault is completely eliminated.

2. The adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization according to claim 1, characterized in that, In step S1, the comprehensive judgment involves the power distribution master station collecting real-time voltage and current data of the power distribution switches and transformer equipment to monitor whether they are in normal condition, thereby judging whether a fault has occurred in the line. The faults include phase loss and grounding faults. If the voltage and current of a certain phase are both zero, it can be judged as a phase loss fault. If the voltage of a certain phase decreases while the voltages of the other two phases increase, it can be judged as a grounding fault.

3. The adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization according to claim 1, characterized in that, In step S2, the segment is an independent closed circuit section defined by adjacent distribution switches.

4. The adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization according to claim 3, characterized in that, In step S2, the dynamic optimization algorithm performs the following sub-steps: Step S2-1, Status Check: Determine whether the total number of segments of the current line has met the preset target; if it has, this step ends directly and the process proceeds to step S3; if it does not meet the target, proceed to step S2-2. Step S2-2, Merging Candidate Selection and Execution: Traverse all current adjacent pair combinations; for each pair of adjacent segments, calculate the sum of their respective transformer capacities; the distribution master station system will select the pair of segments with the smallest total capacity as the best merging object, execute the merging operation, and form a new, larger segment; Repeat steps S2-1 to S2-2 until the number of segments meets the requirement.

5. The adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization according to claim 1, characterized in that, In step S3, the main line refers to the line from the outgoing switch of the power distribution line to each tie switch; if there are multiple tie switches in the power distribution line, then the line contains multiple main lines; if there are no tie switches in the power distribution line, then the line with the most segments is the main line.

6. The adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization according to claim 5, characterized in that, In step S3, the longest trunk line specifically refers to the trunk line with the largest number of sectionalizing switches after segmentation and merging; if no sectionalizing switches are configured between the outgoing switches of the distribution line and each tie switch, the outgoing switches are directly tested and the entire process ends; if the number of sectionalizing switches is the same for multiple trunk lines, they are tested according to the switch number.

7. The adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization according to claim 1, characterized in that, In step S5, the re-collection of terminal signals refers to the power distribution master station actively issuing a data collection instruction, requiring terminal equipment such as power distribution switches and transformers to upload their latest voltage and current data in real time.

8. The adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization according to claim 1, characterized in that, In step S6, the tie switch refers to a switch connected to the opposite line. When closed, the load in this section can be powered by the opposite line. The preferred strategy refers to selecting the most suitable tie switch to perform the power transfer by comprehensively considering the real-time load rate of the opposite line and the importance level of the user supplied.

9. The adaptive recovery method for multi-segment, multi-tie distribution network faults based on dynamic optimization according to claim 1, characterized in that, In step S7, the better connection point refers to a connection switch between the tested switch and the switch to be tested. If there is a connection switch between the connection switch and the switch to be tested, and the connection switch and the switch to be tested still contain a section switch, then the connection switch is considered a better connection point. With the help of such connection points, more precise load division and transfer can be achieved, thereby reducing the power outage area. If there are multiple better connection points that meet the conditions, the test and transfer operations are carried out in order of the number of line sections corresponding to each connection point from most to least.

10. An adaptive recovery system for multi-segment, multi-tie distribution network faults based on dynamic optimization, comprising a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executed by the processor; characterized in that, When the system is running, the processor and the memory communicate via a bus, and the machine-readable instructions are executed by the processor as described in any one of claims 1 to 9. This is an adaptive recovery method for multi-segment multi-connection distribution network faults based on dynamic optimization.

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