Micro-grid short-circuit fault multi-point cooperative protection method and device adaptive to topology change

Abstract

The application provides a micro-grid short-circuit fault multi-point cooperation protection method and device with adaptive topological change, adopts a multi-point cooperation protection strategy to detect and locate a short-circuit fault of the micro-grid, utilizes early detection advantages of wavelet change to realize early detection and regional location of the fault at the edge side of the micro-grid, and adopts a "communication also relay" strategy to realize an advantage function of adaptive micro-grid topological structure change; the embodiment can adaptively change the micro-grid topological structure, does not need to use a complex algorithm to locate the fault, simultaneously meets early detection and regional location requirements of the fault, and has good accuracy and practicability.

Description

Technical Field

[0001] This invention belongs to the field of microgrid short-circuit fault handling technology, and particularly relates to a method and device for multi-point cooperative protection of microgrid short-circuit faults that adapts to topology changes. Background Technology

[0002] In recent years, with the further expansion of global energy utilization, the reserves of traditional energy resources have become increasingly scarce. Renewable energy has attracted increasing attention. Developing new energy power generation technologies such as photovoltaic power generation and wind power generation has become a consensus across society. New energy power generation technologies represented by these new energy sources are booming. Renewable energy sources such as solar and wind power are connected to the grid in the form of distributed power sources. Traditional power grids cannot perfectly accommodate distributed power sources, thus microgrid technology has received widespread attention. Microgrid technology is not entirely the same as traditional power grids. Due to its internal structure with multiple distributed power sources, it generally needs to rely on power electronic conversion devices to supply power to the load, and cannot directly supply power to the load as in traditional power grids. Therefore, fault detection technologies of traditional power grids are not entirely suitable for microgrid systems, and further research is needed on fault detection and location technologies suitable for microgrid systems.

[0003] Short-circuit fault detection and location technology is a key aspect of microgrid technology. Currently, most domestic and international research still utilizes short-circuit fault characteristic quantities such as short-circuit current for fault detection and location. For example, faults are detected and located based on the positive and negative sequence components of the fault current, changes in phase angle, or changes in power direction. While this method of measuring fault-related electrical quantities is relatively simple, it requires a considerable time after the fault occurs, making it difficult to meet the requirements for early and rapid fault detection. Besides direct detection using fault electrical quantities, traveling wave detection is also popular, but this method requires timely handling of reflected wave effects and has high requirements for measurement synchronization, timing, and data accuracy, and is easily affected by line parameters. Currently, the use of wavelet transform methods for early detection of short-circuit faults in microgrids has received considerable attention. While this method meets the requirement for early fault detection, its fault location method requires knowledge of the microgrid's topology. When the microgrid's topology changes during normal load switching, the topology information needs to be obtained again, and complex algorithm calculations are required to relocate the fault area in the new topology. Current fault detection and protection methods all require that the power grid topology remain unchanged. Any change in the microgrid topology caused by normal switching operations will lead to the failure of fault detection. The changed topology parameters need to be updated and recalculated in the original algorithm to adapt to the new microgrid structure. Summary of the Invention

[0004] To overcome the defects and shortcomings of existing technologies, this invention provides a multi-point cooperative protection method and device for microgrid short-circuit faults that adapts to topology changes. It employs a multi-point cooperative protection strategy to detect and locate short-circuit faults in the microgrid. Utilizing the early detection advantage of wavelet transforms, it achieves early fault detection and regional location at the microgrid edge. Furthermore, it adopts a "communication as relay" strategy to realize the advantages of adapting to changes in microgrid topology. This embodiment can adapt to changes in microgrid topology without using complex algorithms for fault location, while simultaneously meeting the requirements for early fault detection and regional location, exhibiting good accuracy and practicality.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A multi-point cooperative protection method for short-circuit faults in microgrids that adapts to topology changes, characterized in that:

[0007] By setting up multiple wireless communication nodes with autonomous control and computing capabilities, adjacent nodes interact with each other, compare the current wavelet energy spectrum data of each node with the wavelet energy spectrum values ​​of adjacent nodes, and compare them with the established fault section judgment threshold to determine the section where the fault point is located, disconnect the circuit breaker to which the fault section belongs, and realize multi-node collaborative control.

[0008] It adopts a "communication can also be relayed" design, using each wireless communication node itself as a relay, realizing long-distance data transmission through short-range communication between nodes, and allowing each node to autonomously judge faults and disconnect the circuit breaker in that section, so as to improve communication and control efficiency.

[0009] After the fault section node completes the fault section location and autonomous control to disconnect the section circuit breaker, the section node transmits the fault section information and the status of the relevant circuit breaker to the adjacent node, which then relays the information to the port, and the port uploads it to the monitoring center.

[0010] During this data transmission process, if the circuit breaker in the faulty section cannot disconnect, the adjacent upstream node will cooperate to control the circuit breaker in this node to disconnect it after receiving the status information of the circuit breaker in the faulty section, so as to realize the backup protection function.

[0011] Furthermore, the feeders of the microgrid are divided into single-node feeders and multi-node feeders. Current data is collected in real time through the feeder port nodes, and wavelet transform is performed to obtain the real-time current wavelet energy spectrum value. The value is compared with the real-time detected current wavelet energy spectrum value according to the set fault detection threshold to determine whether a short-circuit fault has occurred.

[0012] If the microgrid feeder being tested contains only one node, then there is no need to perform fault location; the fault information can be directly transmitted by the port communication node.

[0013] If the feeder contains multiple nodes, including various distributed power sources and loads, then multiple collaborative control nodes with autonomous control and computing capabilities are set up on the feeder. Only adjacent nodes exchange electrical data. The current wavelet energy spectrum values ​​of adjacent nodes are compared and judged according to the set fault location threshold. If the fault location threshold judgment condition is met, it is considered that a short circuit fault has occurred in the section between adjacent nodes, that is, an intra-zone fault has occurred. Otherwise, it is considered that the fault is an extra-zone fault. After the intra-zone fault area is determined, the nodes in the fault section autonomously control and disconnect the circuit breaker in the fault section. The fault information and the circuit breaker status are relayed to the feeder port node through the adjacent nodes, and the feeder port node uploads the fault information.

[0014] A microgrid short-circuit fault multi-point cooperative protection device with adaptive topology change, characterized in that: based on the microgrid short-circuit fault multi-point cooperative protection method with adaptive topology change as described above, it includes:

[0015] Detection module: Multiple detection points are set up on each feeder of the microgrid. The detection points acquire real-time current signals collected by current sensors, denoted as P1~P2. n The module, and through signal processing modules N1~N n The original acquired signal is subjected to noise reduction and filtering processing, and the processed current signal acquired by the detection module is transmitted to the control and protection module through the cooperation module.

[0016] Collaboration Module: Based on the edge computing strategy, communication only occurs between adjacent nodes. These adjacent nodes exchange electrical information, denoted as M1~M2. n-1 Furthermore, each node possesses autonomous computing capabilities, enabling fault diagnosis and location processing within the control and protection module;

[0017] Control and protection module: Data exchange is only performed between two adjacent communication nodes. The multiple communication nodes located on the multi-node feeder are not only communication nodes but also relay nodes, possessing autonomous control and computing capabilities. The feeder port nodes determine the fault type based on the detected current information. Each communication node calculates its wavelet energy spectrum value by performing wavelet transform algorithm on the real-time detected current of its own node. Combined with the received wavelet energy spectrum values ​​of adjacent nodes, it autonomously performs fault location processing and controls the opening and closing of the circuit breaker in its section based on the fault location result.

[0018] Furthermore, 250 times the maximum current wavelet energy spectrum value of the normal operation in each node area of ​​the microgrid is taken as the fault detection threshold, and each node completes the short circuit fault detection in its responsible area.

[0019] For multi-node feeders, different sections are divided according to the distribution of detection nodes. The specific method for locating faulty sections is as follows:

[0020] Step S1: Each node detects the real-time current and performs wavelet transform to obtain the current wavelet energy spectrum value;

[0021] Step S2: Define the node closer to the feeder port among two adjacent nodes as Y, and the other node as X. The upper limit is the ratio of wavelet energy spectrum of Y and X when a single-phase short circuit fault occurs between Y and X and the initial phase angle of the fault is 150 degrees. The lower limit is the ratio of the maximum wavelet energy spectrum of Y and X when the load is switched between Y and X during non-fault operation. Select the fault section location judgment threshold within this interval. If the ratio of energy spectrum of Y and X is greater than the threshold, it is considered that the adjacent node has a fault within the zone; otherwise, a short circuit fault has occurred outside the zone.

[0022] According to this judgment method, the faulty section is identified and the faulty section is located. After the fault detection and section location are completed, the faulty section node will autonomously control the circuit breaker in that section to open and send the faulty section location information and the circuit breaker status information to the feeder port node through relay transmission between adjacent nodes. The port node will then upload the fault information and circuit breaker status information to the monitoring center, thus completing the multi-node collaborative control strategy. If the circuit breaker in the faulty section does not operate normally, other communication nodes that receive abnormal circuit breaker status information can provide backup protection during this process.

[0023] Compared with existing technologies, this invention and its preferred embodiment employ "edge computing" and "communication as relay" strategies. Each communication node only communicates with its adjacent nodes and possesses autonomous control and computing capabilities. Therefore, this solution can adapt to changes in the microgrid topology and continue fault detection and location even when the microgrid is normally switching loads and the topology changes. Due to the influence of the multi-point cooperation strategy, the distance between adjacent communication nodes is very small, meaning the communication delay between adjacent nodes is small and the impact of disturbances is minimal. Each communication node autonomously performs wavelet transform on the real-time current detected at its own node. After determining the fault section, it can autonomously perform fault protection first and then transmit the fault information. Therefore, the impact of communication on early fault detection is negligible. On the other hand, this method only uses the wavelet transform algorithm, eliminating the need for complex algorithm calculations for fault section location. Therefore, this solution is more efficient and practical. Theoretically, this method is applicable to microgrid systems of arbitrary length and arbitrary topology.

[0024] It combines edge computing and multi-point cooperative communication technology that can also relay communication, which not only meets the requirements for early detection of microgrid faults, but also solves the adaptive problem when the microgrid topology changes. It avoids a lot of complex algorithm calculations for fault location, reduces the amount of communication data and computation, and effectively improves the efficiency and practicality of microgrid fault detection methods. Attached Figure Description

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0026] Figure 1 This is a flowchart of the microgrid short-circuit fault early detection and location method according to an embodiment of the present invention.

[0027] Figure 2 This is a simplified topology diagram of the microgrid short-circuit fault early detection and location method according to an embodiment of the present invention.

[0028] Figure 3 This is a structural diagram of the microgrid short-circuit fault early detection and location strategy according to an embodiment of the present invention. Detailed Implementation

[0029] To make the features and advantages of this patent more apparent and understandable, specific embodiments are provided below for detailed explanation:

[0030] 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 in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0031] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments 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.

[0032] The detection and location technology of short-circuit faults in microgrids is one of the key technologies currently restricting the development of practical applications of microgrids. This embodiment is applicable to radial microgrids. Combining the application of wavelet transform in microgrid fault detection, it sets appropriate fault detection and fault segment judgment thresholds, and compares the real-time detected current wavelet energy spectrum values. Compared with the single-point wavelet transform fault location method, which has poor adaptability to changes in microgrid topology, this embodiment achieves the function of adaptive microgrid topology changes at the edge of the microgrid. By setting up multiple wireless communication nodes with autonomous control and computing capabilities, adjacent nodes exchange data, compare the current wavelet energy spectrum data of each node with the wavelet energy spectrum values ​​of adjacent nodes, and compare them with the established fault segment judgment threshold to determine the segment where the fault point is located. The circuit breaker of the fault segment is then disconnected, realizing multi-node collaborative control.

[0033] Meanwhile, the design of "communication can also be relayed" utilizes each wireless communication node itself as a relay to achieve long-distance data transmission through short-distance communication between nodes. Furthermore, each node can autonomously determine the fault and disconnect the circuit breaker in that section, improving communication and control efficiency. Therefore, this method meets the requirements for early detection and location of faults and is not affected by changes in the microgrid topology.

[0034] After a faulty section node completes fault location and autonomous control to disconnect the circuit breaker in that section, the node transmits the fault information and related circuit breaker status to adjacent nodes. These adjacent nodes then relay the information to the port, which in turn uploads it to the monitoring center. During this data transmission process, if the faulty section circuit breaker cannot disconnect, the adjacent upstream node, upon receiving the faulty section circuit breaker status information, will perform cooperative control to disconnect its own circuit breaker, thus providing backup protection. Compared to single-point wavelet change detection methods, this embodiment employs a multi-point cooperative method to complete early fault detection and location protection control at the microgrid edge. It utilizes multi-node relays for long-distance data communication, adapting to changes in the microgrid topology and eliminating the need for complex algorithms for fault location, resulting in higher efficiency in fault location.

[0035] The flowchart of this embodiment is as follows: Figure 1 As shown, a simplified topology diagram is as follows: Figure 2 As shown.

[0036] like Figure 2 As shown, this embodiment divides the microgrid feeders into single-node feeders and multi-node feeders. Current data is collected in real time through the feeder port nodes, and wavelet transform is performed to obtain the real-time current wavelet energy spectrum value. The current wavelet energy spectrum value is compared with a set fault detection threshold to determine whether a short-circuit fault has occurred. If the detected microgrid feeder contains only one node, fault location is unnecessary; fault information is directly transmitted by the port communication node. If the feeder contains multiple nodes, i.e., various distributed power sources and loads, multiple collaborative control nodes with autonomous control and computing capabilities need to be set up on the feeder. Electrical data is only transmitted between adjacent nodes. The current wavelet energy spectrum values ​​of adjacent nodes are compared based on a set appropriate fault segment location threshold. If the fault location threshold is met, a short-circuit fault is considered to have occurred in the segment between adjacent nodes, i.e., an intra-fault; otherwise, the fault is considered an extra-fault. After identifying the faulty area within the zone, the nodes in the faulty section autonomously control and disconnect the circuit breaker in the faulty section. The fault information and the status of the circuit breaker are then relayed to the feeder port node through adjacent nodes, and the feeder port node uploads the fault information.

[0037] This invention primarily utilizes an "edge computing" strategy to achieve early detection of short-circuit faults in microgrids, and employs a "communication relay" strategy for fault location. This means communication occurs only between adjacent nodes, and each node possesses edge computing capabilities. It performs wavelet transform calculations on the current at its own node and compares this with the wavelet energy spectrum values ​​of the current transmitted from adjacent nodes to complete the fault location judgment. Furthermore, it can autonomously control circuit breakers within the node's area. This method balances early detection with adaptability to topology changes. The structural diagram of this embodiment is shown below. Figure 3 As shown.

[0038] The device in this embodiment is divided into three main modules:

[0039] (1) Detection module (module 1): Multiple detection points are set up on each feeder of the microgrid. The detection points acquire the real-time current signal collected by the current sensor, which is P1~P n Because the raw current acquisition signal contains harmonics and other impurities, signal processing modules N1~N are required. n The original acquired signal is subjected to noise reduction and other filtering processes. Finally, the processed current signal acquired by the detection module is transmitted to the control and protection module (module 3) through the cooperation module (module 2).

[0040] (2) Collaboration Module (Module 2): According to the "edge computing" strategy, communication only occurs between adjacent nodes. Each adjacent node transmits electrical information, i.e., M1~M n-1 Furthermore, each node possesses autonomous computing capabilities, enabling fault diagnosis and location processing in Module 3.

[0041] (3) Control and Protection Module (Module 3): This module only exchanges data between two adjacent communication nodes. The multiple communication nodes on this multi-node feeder are not only communication nodes but also relay nodes, possessing autonomous control and computational capabilities. Each communication node can calculate its wavelet energy spectrum value using a wavelet transform algorithm on the real-time detected current of its node. Combined with the received wavelet energy spectrum values ​​from adjacent nodes, it autonomously performs fault location processing and controls the opening and closing of the circuit breaker in its section based on the fault location results.

[0042] A fault detection threshold is selected as 250 times the maximum current wavelet energy spectrum value during normal operation in each node area of ​​the microgrid. Each node can independently complete short-circuit fault detection within its responsible area. For multi-node feeders, different sections are divided according to the distribution of detection nodes. The specific method for locating fault sections is as follows:

[0043] ① Each node detects the real-time current and performs wavelet transform to obtain the current wavelet energy spectrum value.

[0044] ② Define the node closer to the feeder among two adjacent nodes as Y, and the other node as X. The upper limit is the ratio of wavelet energy spectrum of Y and X when a single-phase short-circuit fault occurs between nodes Y and X and the initial phase angle of the fault is 150 degrees. The lower limit is the ratio of the maximum wavelet energy spectrum of Y and X when the load is switched between Y and X during non-fault operation. A reasonable fault segment location judgment threshold is selected in this interval. When the ratio of energy spectrum of Y and X is greater than the threshold, it is considered that the adjacent node has a fault within the zone. Otherwise, a short-circuit fault has occurred outside the zone.

[0045] Based on this judgment method, the faulty section can be identified, thus achieving the goal of fault section location. After completing fault detection and section location, the faulty section node will autonomously control the circuit breaker in that section to open, and transmit the faulty section location information and the circuit breaker status information to the feeder port node through relay transmission between adjacent nodes. The port node then uploads the fault information and circuit breaker status information to the monitoring center, thereby completing the multi-node collaborative control strategy. If the circuit breaker in the faulty section fails to operate normally, other communication nodes that receive abnormal circuit breaker status information can provide backup protection during this process.

[0046] In this scheme, due to the adoption of the "edge computing" and "communication as relay" strategies, each communication node only communicates with its adjacent nodes and possesses autonomous control and computing capabilities. Therefore, in the event of normal load switching and topology changes in the microgrid, this embodiment can adapt to the changes in the microgrid topology and continue fault detection and location. Due to the influence of the multi-point cooperation strategy, the distance between adjacent communication nodes is very small, meaning the communication delay between adjacent nodes is small and the impact of disturbances is minimal. Each communication node autonomously performs wavelet transform on the real-time current detected at its own node. After determining the fault segment, it can autonomously implement fault protection first before transmitting the fault information. Therefore, the impact of communication on early fault detection is negligible. Furthermore, this method only uses the wavelet transform algorithm, eliminating the need for complex algorithm calculations for fault segment location. Therefore, this method is more efficient and practical. Theoretically, this method is applicable to microgrid systems of arbitrary length and topology.

[0047] The function shown in module A is to detect and update the zero-crossing information of the current signal transmitted by the communication module. The function shown in module T is to perform a fourth-scale wavelet energy spectrum transform on the transmitted current signal to obtain the current wavelet energy spectrum value. The function shown in module D is to compare the current wavelet energy spectrum value with the fault detection threshold. If the current wavelet energy spectrum value is less than the fault determination threshold, it is considered that no short-circuit fault has occurred in the feeder of the microgrid, and the process returns to the previous step and repeats. If the current wavelet energy spectrum value is greater than the fault determination threshold, it is considered that a short-circuit fault has occurred in the feeder of the microgrid. The type of short-circuit fault is determined by comparing the positive-sequence, negative-sequence, and zero-sequence components of the current at the detection node. If the detected current contains a zero-sequence component, it is considered to have a ground fault. If the detected current contains a positive-sequence component, it is considered to have a three-phase short-circuit fault. If the detected current does not contain a zero-sequence component but contains a negative-sequence component, it is considered to have a two-phase short-circuit fault. This is how the fault type is determined, as shown in module F. For single-node feeders, the feeder circuit breaker is directly disconnected and the fault type information is uploaded, as shown in module B. In addition to determining the fault type and uploading fault type information as shown in module F, multi-node feeders also need to compare the current wavelet energy value of each adjacent node with the fault section location threshold. When two adjacent detection points meet the fault section location judgment conditions shown in ①②, the module determines the fault section based on the relationship between the current wavelet energy spectrum value of the two adjacent nodes and the fault section location judgment threshold. The node in this section autonomously controls the circuit breaker to perform fault section protection and transmits fault section information and circuit breaker status information to adjacent nodes near the feeder side. The fault information is transmitted to the port, i.e., module I, through relay transmission from each node to adjacent nodes. Finally, module B uploads the fault information.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

[0049] This patent is not limited to the above-described preferred embodiments. Anyone can derive other forms of adaptive topology-changing microgrid short-circuit fault multi-point cooperative protection methods and devices based on the teachings of this patent. All equivalent changes and modifications made within the scope of the claims of this invention shall fall within the scope of this patent.

Claims

1. A multi-point cooperative protection method for short-circuit faults in microgrids that adapts to topology changes, characterized in that: By setting up multiple wireless communication nodes with autonomous control and computing capabilities, adjacent nodes interact with each other, compare the current wavelet energy spectrum data of each node with the wavelet energy spectrum values ​​of adjacent nodes, and compare them with the established fault section judgment threshold to determine the section where the fault point is located, disconnect the circuit breaker to which the fault section belongs, and realize multi-node collaborative control. It adopts a "communication can also be relayed" design, using each wireless communication node itself as a relay to achieve long-distance data transmission through short-range communication between nodes, and allows each node to autonomously judge faults and disconnect the circuit breaker in that section to improve communication and control efficiency. After the fault section node completes the fault section location and autonomous control to disconnect the section circuit breaker, the section node transmits the fault section information and the status of the relevant circuit breaker to the adjacent node, which then relays the information to the port, and the port uploads it to the monitoring center. During this data transmission process, if the circuit breaker in the faulty section cannot complete the disconnection, the adjacent upper-level node will cooperate to control the disconnection of the circuit breaker in this node after obtaining the status information of the circuit breaker in the faulty section, so as to realize the backup protection function. The microgrid feeders are divided into single-node feeders and multi-node feeders. Current data is collected in real time through the feeder port nodes, and wavelet transform is performed to obtain the real-time current wavelet energy spectrum value. The value is compared with the real-time detected current wavelet energy spectrum value based on the set fault detection threshold to determine whether a short-circuit fault has occurred. If the microgrid feeder being tested contains only one node, then there is no need to perform fault location; the fault information can be directly transmitted by the port communication node. If the feeder contains multiple nodes, i.e., various distributed power sources and loads, then multiple collaborative control nodes with autonomous control and computing capabilities are set up on the feeder. Only adjacent nodes exchange electrical data. The current wavelet energy spectrum values ​​of adjacent nodes are compared and judged according to the set fault location threshold. If the fault location threshold judgment condition is met, it is considered that a short circuit fault has occurred in the section between adjacent nodes, i.e., an intra-zone fault has occurred. Otherwise, it is considered that the fault is an extra-zone fault. After the intra-zone fault area is determined, the nodes in the fault section autonomously control and disconnect the circuit breaker in the fault section. The fault information and the status of the circuit breaker are relayed to the feeder port node through the adjacent nodes, and the feeder port node uploads the fault information. The fault detection threshold is set as 250 times the maximum current wavelet energy spectrum value of the normal operation in each node area of ​​the microgrid. Each node completes the short circuit fault detection in its responsible area. For multi-node feeders, different sections are divided according to the distribution of detection nodes. The specific method for locating faulty sections is as follows: Step S1: Each node detects the real-time current and performs wavelet transform to obtain the current wavelet energy spectrum value; Step S2: Define the node closer to the feeder port among two adjacent nodes as Y, and the other node as X. The upper limit is the ratio of wavelet energy spectrum of Y and X when a single-phase short circuit fault occurs between Y and X and the initial phase angle of the fault is 150 degrees. The lower limit is the ratio of the maximum wavelet energy spectrum of Y and X when the load is switched between Y and X during non-fault operation. Select the fault section location judgment threshold within this interval. If the ratio of energy spectrum of Y and X is greater than the threshold, it is considered that the adjacent node has a fault within the zone; otherwise, a short circuit fault has occurred outside the zone. Based on this judgment method, the faulty section is determined and the faulty section is located. After completing fault detection and section location, the faulty section node will autonomously control the circuit breaker in that section to disconnect and transmit the faulty section location information and the status information of the circuit breaker in that section to the feeder port node through relay transmission between adjacent nodes. The port node will then upload the fault information and circuit breaker status information to the monitoring center, thus completing the multi-node collaborative control strategy. If the circuit breaker in the faulty section fails to operate normally, other communication nodes that receive abnormal circuit breaker status information will provide backup protection during this process.

2. A microgrid short-circuit fault multi-point cooperative protection device with adaptive topology change, characterized in that: The microgrid short-circuit fault multi-point cooperative protection method based on adaptive topology change as described in claim 1 includes: Detection module: Multiple detection points are set up on each feeder of the microgrid. The detection points acquire real-time current signals collected by current sensors, denoted as P1~P2. n The module, and through signal processing modules N1~N n The original acquired signal is subjected to noise reduction and filtering processing, and the processed current signal acquired by the detection module is transmitted to the control and protection module through the cooperation module. Collaboration Module: Based on the edge computing strategy, communication only occurs between adjacent nodes. These adjacent nodes exchange electrical information, denoted as M1~M2. n-1 Furthermore, each node possesses autonomous computing capabilities, enabling fault diagnosis and location processing within the control and protection module; Control and protection module: Data exchange is only performed between two adjacent communication nodes. The multiple communication nodes located on the multi-node feeder are not only communication nodes but also relay nodes, possessing autonomous control and computing capabilities. The feeder port nodes determine the fault type based on the detected current information. Each communication node calculates its wavelet energy spectrum value by performing wavelet transform algorithm on the real-time detected current of its own node. Combined with the received wavelet energy spectrum values ​​of adjacent nodes, it autonomously performs fault location processing and controls the opening and closing of the circuit breaker in its section based on the fault location result.

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