High-voltage distribution network hybrid overhead line fault isolation method and system based on synchronous phasor measurement

Abstract

The application discloses a high-voltage distribution network mixed overhead line fault isolation method and system based on synchronous phasor measurement, relates to the technical field of fault isolation, and comprises the following steps: collecting synchronous phasor unit data along a main line trunk path in sequence, detecting abnormal nodes on the main line trunk path to obtain a first abnormal node set; extending abnormal nodes in the first abnormal node set along branch paths in stages to obtain a first fault path set and detecting whether there is a synchronous phasor unit to obtain a region without a synchronous phasor unit; constructing a virtual node in the region without the synchronous phasor unit, constructing a virtual node abnormality detection model; screening the first fault path set based on the output of the virtual node abnormality detection model to obtain a second fault path set, and performing rapid fault isolation based on the second fault path set, so that the problem of how to accurately judge the fault state of the main line trunk path and each branch line when a fault occurs at a branch point is solved.

Description

Technical Field

[0001] This invention relates to the field of fault isolation technology, and more specifically, to a fault isolation method and system for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement. Background Technology

[0002] With the gradual upgrading of modern high-voltage power distribution networks, especially the widespread application of hybrid overhead lines in high-voltage distribution networks, the structure and operation of power grids are undergoing profound changes. As urban and rural power grids are continuously transformed and upgraded, more and more regions are adopting more stable and efficient cable lines, while some remote areas and third- and fourth-tier cities still rely primarily on overhead lines. This hybrid application of overhead and cable lines, while improving power grid reliability, also leads to imbalances in line structure and inconsistencies in electrical parameters, posing significant challenges to fault diagnosis and protection system design. Especially during fault occurrences, the different characteristics of overhead and cable lines make fault conditions more complex, increasing the difficulty of traditional fault finding and location methods, and consequently making the design and coordination of relay protection systems more complex.

[0003] However, most high-voltage distribution lines adopt a layered, dendritic topology, resulting in numerous branch lines. Especially at the junctions of main lines and branch lines, fault diagnosis information is often redundant and difficult to clearly distinguish. This structural characteristic makes it a major challenge to quickly and accurately locate the faulty line and isolate the faulty area when a fault occurs. Especially when the fault occurs at a branch point, accurately determining the fault status of the main line and each branch line is the core issue of power grid fault isolation. To address these problems, this invention proposes a solution. Summary of the Invention

[0004] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide a fault isolation method and system for high-voltage distribution network mixed overhead lines based on synchronous phasor measurement. This method and system address the problem of accurately determining the fault status of the main line and each branch line when a fault occurs in a mixed overhead line with a large number of branch lines.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement includes the following steps: Synchronous phasor unit data are collected sequentially along the main path; abnormal nodes on the main path are detected to obtain a first abnormal node set; based on the hybrid overhead line topology diagram, the abnormal nodes in the first abnormal node set are extended step-by-step along branch paths to obtain a first fault path set; the presence or absence of synchronous phasor units in the fault paths of the first fault path set is detected to obtain several regions without synchronous phasor units; virtual nodes are constructed in the regions without synchronous phasor units, and a virtual node anomaly detection model is constructed based on the electrical data of synchronous phasor units adjacent to the virtual nodes; the first fault path set is filtered based on the output of the virtual node anomaly detection model to obtain a second fault path set, and rapid fault isolation is performed based on the second fault path set.

[0007] In a preferred embodiment, the step of sequentially collecting synchronization phasor unit data along the main path and detecting abnormal nodes on the main path to obtain a first abnormal node set specifically involves: starting from the substation starting point along the main path, sequentially collecting synchronization phasor unit data for each node, wherein the synchronization phasor unit data includes the node's measured voltage amplitude, the node's measured current amplitude, and the node's measured frequency; inputting the node's measured voltage amplitude, the node's measured current amplitude, and the node's measured frequency into a preset abnormal node detection model to obtain a node comprehensive evaluation value; when the node's comprehensive evaluation value is greater than a preset threshold, the node is identified as an abnormal node.

[0008] In a preferred embodiment, the step of extending the abnormal nodes in the first abnormal node set along the branch paths step by step based on the hybrid overhead line topology diagram to obtain the first fault path set specifically involves: obtaining hybrid overhead line paths based on the hybrid overhead line topology diagram, wherein the hybrid overhead line paths include trunk paths and all branch paths; taking the abnormal nodes in the first abnormal node set as the starting point and determining whether the abnormal nodes are branch nodes; if they are branch nodes, extending the branch nodes step by step until the end of the branch to obtain several suspected fault paths; merging and deduplicating the several suspected fault paths to obtain the first fault path set.

[0009] In a preferred embodiment, detecting whether a fault path in the first fault path set has a synchronization phasor unit to obtain several regions without synchronization phasor units specifically involves: detecting whether a node on each path in the first fault path set has a synchronization phasor unit; if all nodes on the path have synchronization phasor units, then the path is retained; if there are nodes on the path without synchronization phasor units, then the path is divided into several regions without synchronization phasor units, and the node before the first node and the node after the last node in the region without synchronization phasor units is determined.

[0010] In a preferred embodiment, a virtual node is constructed in the region without synchronization phasor units, and an anomaly detection model for the virtual node is constructed based on the electrical data of the synchronization phasor units adjacent to the virtual node. Specifically, a virtual node is constructed in each node of the region without synchronization phasor units; the virtual node inherits the position and topological connection relationship of the nodes without synchronization phasor units; the electrical data of the synchronization phasor units adjacent to the virtual node is obtained, and the target electrical data of the virtual node is obtained based on the interpolation calculation formula.

[0011] In a preferred embodiment, the first fault path set is filtered based on the output of the virtual node anomaly detection model to obtain a second fault path set, and rapid fault isolation is performed based on the second fault path set. Specifically, the target electrical data of the virtual node is input into a preset virtual node anomaly detection model to obtain a virtual node anomaly evaluation value; if the virtual node anomaly evaluation value is greater than a preset threshold, the virtual node is designated as an anomaly node; the anomaly nodes on the fault paths in the first fault path set are updated based on the virtual nodes to obtain an updated fault path set; the updated fault path set is filtered based on a path redundancy removal calculation formula to obtain a second fault path set; and rapid fault isolation is performed on the high-voltage distribution network hybrid overhead line based on the second fault path set.

[0012] The technical effects and advantages of the fault isolation method and system for high-voltage distribution network hybrid overhead lines based on synchronous phasor measurement in this invention are as follows:

[0013] 1. This invention, by sequentially collecting synchronous phasor unit (PMU) data along the main trunk line, can accurately detect abnormal nodes in real time, improving the sensitivity and accuracy of fault identification. Secondly, by combining the hybrid overhead line topology, abnormal nodes are extended step-by-step along branch paths, comprehensively covering complex line topologies and ensuring the integrity of fault location. For areas without PMU coverage, a novel virtual node is introduced, using electrical data from adjacent PMUs for interpolation calculations and constructing an anomaly detection model, effectively solving the problem of fault blind spots in unmonitored areas. The virtual node model, combined with multi-dimensional electrical parameter variation characteristics, significantly enhances the robustness and accuracy of fault path selection. Furthermore, by selecting an optimized second fault path set from the first fault path set, a fault area can be quickly and accurately isolated while power is restored to non-faulty areas, greatly reducing the scope and duration of power outages. The overall method not only improves the speed and reliability of fault isolation but also reduces dependence on PMU equipment through virtual node technology, exhibiting good economic efficiency and scalability, and is suitable for the intelligent operation and management of complex high-voltage distribution networks. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement according to the present invention.

[0015] Figure 2 This is a schematic diagram of the fault isolation system for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement, as described in this invention. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0017] Example 1, Figure 1 This invention presents a fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement, characterized by the following steps:

[0018] S1, collect synchronous phasor unit data sequentially along the main path, and detect abnormal nodes on the main path to obtain the first abnormal node set;

[0019] In this example, synchronization phasor unit data is collected sequentially along the main path, and abnormal nodes on the main path are detected to obtain the first set of abnormal nodes, specifically:

[0020] Along the main path, starting from the substation, the synchronization phasor unit data of each node is collected sequentially. The synchronization phasor unit data includes the measured voltage amplitude, measured current amplitude, and measured frequency of the node.

[0021] The measured voltage amplitude, measured current amplitude, and measured frequency of the node are input into a preset abnormal node detection model to obtain a comprehensive evaluation value of the node.

[0022] When the overall evaluation value of a node exceeds a preset threshold, the node is considered an abnormal node.

[0023] The pre-defined abnormal node detection model is as follows:

[0024] in, This is the comprehensive evaluation value for the nodes. , and These are the weighting coefficients for the measured voltage amplitude, measured current amplitude, and deviation from the measured frequency, respectively. Let i be the measured voltage amplitude at node i. The voltage reference value set for the system. Let i be the measured current amplitude at node i. The current reference value set for the system, The frequency reference value set for the system, Let i be the measured frequency of node i. , and These are the permissible deviation ranges for voltage, current, and frequency, respectively.

[0025] It should be noted that by sequentially collecting synchronous phasor unit data along the main trunk line path and combining it with a pre-set abnormal node detection model, the detection accuracy and efficiency of abnormal nodes in high-voltage distribution networks are significantly improved. First, by comprehensively collecting three key electrical parameters—measured voltage amplitude, measured current amplitude, and measured frequency—a multi-dimensional data foundation is provided for anomaly detection, avoiding misjudgments that may result from a single parameter and improving the comprehensiveness and robustness of the detection. Second, by introducing an abnormal node detection model and fusing and evaluating multiple electrical parameters, the operating status of the node can be more accurately reflected, enabling accurate identification of abnormal nodes in complex electrical environments. The formula compares the comprehensive evaluation value with a pre-set threshold, making the detection process highly flexible and adaptable. Parameter thresholds can be adjusted according to different power grid conditions to optimize the detection effect.

[0026] Furthermore, the method of collecting data node by node from the substation starting point ensures comprehensive coverage of all critical nodes along the main path, facilitating the formation of a complete set of abnormal nodes and laying the foundation for subsequent fault location and isolation. Compared to traditional methods, this approach shortens the response time for fault detection through online real-time detection and evaluation, making it particularly suitable for abnormal node detection needs in complex hybrid overhead line environments. Overall, this method not only improves the accuracy and reliability of abnormal node detection but also significantly enhances the efficiency of power grid fault management, further ensuring the safe and stable operation of the power grid.

[0027] S2, Based on the hybrid overhead line topology diagram, the abnormal nodes in the first abnormal node set are extended step by step along the branch path to obtain the first fault path set;

[0028] In this example, based on the hybrid overhead line topology diagram, the abnormal nodes in the first abnormal node set are extended step by step along the branch paths to obtain the first fault path set, specifically:

[0029] The hybrid overhead line path is obtained based on the hybrid overhead line topology diagram, and the hybrid overhead line path includes the trunk path and all branch paths.

[0030] Take the abnormal nodes in the first abnormal node set as the starting point and determine whether the abnormal nodes are branch nodes.

[0031] If it is a branch node, then the branch node is extended level by level until the end of the branch to obtain several suspected fault paths;

[0032] The suspected fault paths are merged and deduplicated to obtain the first fault path set.

[0033] It should be noted that obtaining the first fault path set by extending the first set of fault paths step-by-step from the first set of anomalous nodes based on the hybrid overhead line topology diagram has significant technical advantages and practical value. Firstly, using the hybrid overhead line topology diagram allows for a comprehensive understanding of the relationship between the main and branch paths, ensuring accurate coverage of fault paths, especially in complex power grid environments. By using anomalous nodes as starting points and determining whether they are branch nodes, it is possible to accurately identify which anomalous nodes belong to branch nodes, thereby effectively distinguishing between main and branch paths, allowing for targeted extensions, avoiding interference from redundant paths, and improving the accuracy of fault path determination.

[0034] Secondly, the strategy of extending branch nodes step by step to the end of the branch fully considers the topological characteristics of the line, ensuring that the propagation path of abnormal signals along the entire line is completely captured. This step-by-step extension method is particularly suitable for the complex tree-structured power networks in high-voltage distribution networks. It can clearly reflect suspected fault paths and accurately construct these paths into the first fault path set, providing reliable data support for subsequent fault location.

[0035] Furthermore, this method effectively reduces the probability of false positives and false negatives by progressively screening suspected fault paths, ensuring the efficiency and accuracy of the fault isolation process. In complex hybrid overhead line systems, it can quickly identify and locate fault sources, greatly improving the speed of power grid fault detection and isolation, reducing recovery time after an accident, and playing a vital role in ensuring the safety, stability, and operational efficiency of the power grid.

[0036] S3, detect whether there are synchronous phasor units in the fault paths of the first fault path set to obtain several regions without synchronous phasor units.

[0037] In this example, detecting whether there are synchronized phasor units in the fault paths of the first fault path set yields several regions without synchronized phasor units, specifically:

[0038] Detect whether there are synchronization phasor units on each node of the first fault path set;

[0039] If all nodes on the path have a synchronized phasor unit, then the path is retained;

[0040] If there are nodes without synchronized phasor units on the path, the path is divided into several regions without synchronized phasor units, and the node before the first node and the node after the last node in each region without synchronized phasor units is determined.

[0041] It should be noted that the process of detecting the presence of synchronization phasor units in the fault paths of the first fault path set and delineating the regions without synchronization phasor units aims to accurately identify areas in the network that are not being monitored in real time. Specifically, each path in the first fault path set is checked one by one. If all nodes on the path have synchronization phasor units installed, the path is considered to have complete monitoring conditions and requires no further processing and is retained. For paths where some nodes do not have synchronization phasor units installed, further delineation is required. The continuous area of ​​nodes without synchronization phasor units in this path is defined as the region without synchronization phasor units. These regions require extra attention because the lack of synchronization phasor data support may lead to a decrease in the accuracy of fault location. Therefore, the boundary nodes of these regions are further determined, namely the node before the first node without synchronization phasor units and the node after the last node without synchronization phasor units, for subsequent virtual node construction and data interpolation processing. The specific advantages are as follows:

[0042] Accurate identification of unmonitored areas: By checking whether synchronous phasor units are installed in the path node by node, areas that cannot be monitored in real time can be quickly located, providing a clear target area for subsequent anomaly detection and handling.

[0043] Clearly defined boundary nodes: By clearly defining the front and rear boundary nodes of the region without synchronous phasor units, accurate basic data is provided for constructing virtual nodes, ensuring that virtual nodes can inherit the characteristics of the actual topology.

[0044] Improve fault isolation efficiency: Separate the covered and uncovered areas of the synchronization phasor unit for processing, effectively simplifying the analysis of complex paths, reducing computational redundancy, and quickly locating potential problem areas.

[0045] Support for subsequent data compensation: By dividing the region of asynchronous phasor units, a clear target range is provided for electrical data compensation based on interpolation calculation, thereby improving the reliability of the virtual node anomaly detection model.

[0046] Enhanced adaptability: This method can flexibly cope with different types of mixed overhead line topologies. Even if there are complex branches and different monitoring conditions in the network, it can accurately delineate unmonitored areas and formulate targeted treatment plans.

[0047] Simplify resource allocation: By effectively filtering out regions without synchronized phasor units, precise guidance can be provided for subsequent equipment upgrades or additional deployments, saving resources and avoiding blind expansion.

[0048] S4, construct a virtual node in the region without synchronous phasor units, and construct a virtual node anomaly detection model based on the electrical data of the synchronous phasor units adjacent to the virtual node;

[0049] In this example, a virtual node is constructed in the region without synchronization phasor units, and an anomaly detection model for the virtual node is constructed based on the electrical data of the synchronization phasor units adjacent to the virtual node. Specifically:

[0050] Construct virtual nodes in each asynchronous phasor cell node in the asynchronous phasor cell region;

[0051] The virtual node inherits the position and topological connection relationship of the node without synchronization phasor unit;

[0052] The electrical data of the adjacent synchronous phasor unit nodes of the virtual node are obtained, and the target electrical data of the virtual node is obtained based on the interpolation calculation formula.

[0053] The interpolation calculation formula is as follows:

[0054]

[0055] in, The target electrical parameters for the virtual node. Preset weights for the influence of the i-th adjacent synchronous phasor unit node on the virtual node. The electrical parameters of the i-th adjacent synchronous phasor unit node are given. This represents the number of adjacent synchronous phasor unit nodes.

[0056] It should be noted that by constructing virtual nodes in areas without phasor units (PMUs) and performing interpolation calculations based on the electrical data of adjacent phasor units, the problem of PMU monitoring blind spots in distribution networks can be effectively solved. Firstly, by constructing virtual nodes at each PMU-less node, the data gaps caused by the lack of phasor unit coverage can be filled. This approach not only overcomes the blind spot problem caused by the sparse PMU layout in traditional distribution networks but also ensures the continuity and integrity of the entire network during monitoring and control.

[0057] Secondly, virtual nodes inherit the location and topological connections of nodes without synchronization phasor units, enabling them to maintain consistent electrical behavior with other nodes in the network. Through this design, virtual nodes are structurally integrated into the existing power grid topology, ensuring the accuracy and reliability of the virtual node model. Simultaneously, this method makes the interpolation results of virtual nodes more closely resemble the actual operating conditions of the power grid, thereby improving the accuracy of data extrapolation.

[0058] By acquiring the electrical data of adjacent synchronous phasor units of the virtual node and using interpolation formulas to obtain the electrical data of the virtual node, the virtual node can not only reflect the missing electrical parameters in the region, but also make reasonable inferences based on real data. The interpolation calculation effectively utilizes the data of adjacent nodes, ensuring the realism and accuracy of the electrical state of the virtual node, and providing reliable input data for subsequent anomaly detection models.

[0059] Overall, this method, through the construction of virtual nodes and precise interpolation calculations, enables high-voltage distribution networks to perform efficient and accurate fault detection and diagnosis even in areas lacking synchronous phasor units. This not only improves the monitoring accuracy of the power grid but also enhances its robustness and fault tolerance in complex environments, promoting the application and development of smart grid technology in distribution networks.

[0060] S5, based on the output of the virtual node anomaly detection model, the first fault path set is filtered to obtain a second fault path set, and rapid fault isolation is performed based on the second fault path set.

[0061] In this example, the first fault path set is filtered based on the output of the virtual node anomaly detection model to obtain a second fault path set, and rapid fault isolation is performed based on the second fault path set, specifically as follows:

[0062] The target electrical data of the virtual node is input into the preset virtual node anomaly detection model to obtain the virtual node anomaly evaluation value;

[0063] If the abnormal evaluation value of the virtual node is greater than a preset threshold, then the virtual node is considered an abnormal node.

[0064] Based on the virtual nodes, the abnormal nodes on the fault paths in the first fault path set are updated to obtain the updated fault path set.

[0065] The updated fault path set is filtered based on the path redundancy removal calculation formula to obtain the second fault path set;

[0066] Rapid fault isolation is performed on the hybrid overhead lines of the high-voltage distribution network based on the second fault path set.

[0067] It should be noted that by introducing a virtual node anomaly detection model, the monitoring blind spots in fault detection and path selection in regions without synchronized phasor units are effectively compensated for. First, the target electrical data of the virtual nodes is input into the virtual node anomaly detection model for evaluation, achieving accurate anomaly detection in regions without synchronized phasor units. After integrating the evaluated anomaly nodes with the first fault path set, the anomaly node information on the fault paths is updated, laying the data foundation for subsequent path selection. Subsequently, the updated fault path set is optimized using a path redundancy removal calculation formula, resulting in a more accurate second fault path set, further reducing fault path redundancy and complexity. Finally, rapid fault isolation is implemented based on the second fault path set, shortening isolation time and improving the efficiency of power grid fault handling.

[0068] Example 2, Figure 2 This invention presents a fault isolation system for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement, comprising an abnormal node detection module, a fault path acquisition model, a synchronous phasor unit detection module, a model construction module, and a fault isolation module.

[0069] The abnormal node detection module is used to collect synchronous phasor unit data sequentially along the main path and detect abnormal nodes on the main path to obtain the first abnormal node set.

[0070] The fault path acquisition model is used to extend the abnormal nodes in the first abnormal node set along the branch paths step by step based on the hybrid overhead line topology diagram to obtain the first fault path set.

[0071] The synchronization phasor unit detection module is used to detect whether there are synchronization phasor units in the fault paths of the first fault path set, and to obtain several regions without synchronization phasor units.

[0072] The model building module is used to build virtual nodes in the region without synchronous phasor units, and to build a virtual node anomaly detection model based on the electrical data of the synchronous phasor units adjacent to the virtual nodes.

[0073] The fault isolation module is used to filter the first fault path set based on the output of the virtual node anomaly detection model to obtain a second fault path set, and to perform rapid fault isolation based on the second fault path set.

[0074] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0075] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0076] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0077] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0078] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0079] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement, characterized in that, Includes the following steps: Acquire synchronization phasor unit data along the main path of the hybrid overhead line and perform data analysis to obtain the first set of abnormal nodes: Along the main path, starting from the substation, collect synchronization phasor unit data for each node in sequence. The synchronization phasor unit data includes the measured voltage amplitude, measured current amplitude, and measured frequency of the node. Input the measured voltage amplitude, measured current amplitude, and measured frequency of the node into the preset abnormal node detection model to obtain the comprehensive evaluation value of the node. When the comprehensive evaluation value of a node is greater than a preset threshold, the node is considered an abnormal node. Based on the hybrid overhead line topology diagram, the abnormal nodes in the first abnormal node set are extended step by step along the branch paths to obtain the first fault path set. The presence of synchronous phasor units in the fault paths of the first fault path set is detected to obtain several regions without synchronous phasor units. Construct virtual nodes in each asynchronous phasor cell node in the asynchronous phasor cell region; The virtual node inherits the location and topological connection relationships of the node without synchronization phasor unit; Obtain the electrical data of the adjacent synchronous phasor unit nodes of the virtual node, and obtain the target electrical data of the virtual node based on the interpolation formula; The target electrical data of the virtual node is input into the preset virtual node anomaly detection model to obtain the virtual node anomaly evaluation value; If the abnormal evaluation value of a virtual node is greater than a preset threshold, the virtual node will be regarded as an abnormal node. The abnormal nodes on the fault paths in the first fault path set are updated based on the virtual nodes to obtain the updated fault path set. The updated fault path set is filtered based on the path redundancy removal calculation formula to obtain the second fault path set; Rapid fault isolation of hybrid overhead lines in high-voltage distribution networks is achieved based on the second fault path set.

2. The fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement according to claim 1, characterized in that, The method based on the hybrid overhead line topology diagram involves extending the abnormal nodes in the first abnormal node set along the branch paths to obtain the first fault path set, specifically: The hybrid overhead line path is obtained based on the hybrid overhead line topology diagram, and the hybrid overhead line path includes the trunk path and all branch paths. Take the abnormal nodes in the first abnormal node set as the starting point and determine whether the abnormal nodes are branch nodes. If it is a branch node, then the branch node is extended level by level until the end of the branch to obtain several suspected fault paths; The suspected fault paths are merged and deduplicated to obtain the first fault path set.

3. The fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement according to claim 2, characterized in that, The presence of synchronization phasor units in the fault paths of the first fault path set is detected to obtain several regions without synchronization phasor units, specifically: Detect whether there are synchronization phasor units on each node of the first fault path set; If all nodes on the path have a synchronized phasor unit, then the path is retained; If there are nodes without synchronized phasor units on the path, the path is divided into several regions without synchronized phasor units, and the node before the first node and the node after the last node in each region without synchronized phasor units is determined.

4. The fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement according to claim 3, characterized in that, The preset abnormal node detection model is specifically as follows: in, This is the comprehensive evaluation value for the nodes. , and These are the weighting coefficients for the measured voltage amplitude, measured current amplitude, and deviation from the measured frequency, respectively. Let i be the measured voltage amplitude at node i. The voltage reference value set for the system. Let i be the measured current amplitude at node i. The current reference value set for the system, The frequency reference value set for the system, Let i be the measured frequency of node i. , and These are the permissible deviation ranges for voltage, current, and frequency, respectively.

5. The fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement according to claim 4, characterized in that, The interpolation calculation formula is as follows: in, The target electrical parameters for the virtual node. Preset weights for the influence of the i-th adjacent synchronous phasor unit node on the virtual node. Let be the electrical parameters of the i-th adjacent synchronous phasor element node. This represents the number of adjacent synchronous phasor unit nodes.

6. The fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement according to claim 5, characterized in that, The path redundancy removal calculation formula is as follows: in, For the second set of fault paths, For the i-th fault path in the updated fault path set, For the j-th fault path in the updated fault path set, This represents the number of fault paths in the updated fault path set.

7. A system using the fault isolation method for hybrid overhead lines in high-voltage distribution networks based on synchronous phasor measurement as described in any one of claims 1-6, characterized in that, It includes an abnormal node detection module, a fault path acquisition model, a synchronization phasor unit detection module, a model building module, and a fault isolation module: The abnormal node detection module is used to collect synchronous phasor unit data sequentially along the main path and detect abnormal nodes on the main path to obtain the first abnormal node set. The fault path acquisition model is used to extend the abnormal nodes in the first abnormal node set along the branch paths step by step based on the hybrid overhead line topology diagram to obtain the first fault path set. The synchronization phasor unit detection module is used to detect whether there are synchronization phasor units in the fault paths of the first fault path set, and to obtain several regions without synchronization phasor units. The model building module is used to build virtual nodes in the region without synchronous phasor units, and to build a virtual node anomaly detection model based on the electrical data of the synchronous phasor units adjacent to the virtual nodes. The fault isolation module is used to filter the first fault path set based on the output of the virtual node anomaly detection model to obtain a second fault path set, and to perform rapid fault isolation based on the second fault path set.

Images