A power distribution network operation fault detection method, system, device and storage medium based on topology reconfiguration

Abstract

The application discloses a power distribution network operation fault detection method, system and device based on topology reconstruction and a storage medium, and belongs to the technical field of power system automation, and comprises the following steps: acquiring real-time operation parameters of a power grid, and establishing a three-dimensional node coordinate system based on a power grid topology structure to calibrate fault points; according to the real-time operation parameters of the power grid, an optimal power grid topology structure protection strategy for current power grid operation is matched, and the operation state of the current power grid after matching is evaluated; based on the operation state evaluation result, dynamic switching of the power grid topology structure protection strategy is performed on the power grid, and the fault points before and after the switching of the power grid topology structure protection strategy are compared and analyzed to identify topology structure changes; based on the topology structure change identification result, the correlation of the fault points before and after the switching is determined to determine the network reconstruction direction and execute a self-healing control strategy. The application significantly improves the fault detection efficiency and accuracy of the power distribution network.

Description

Technical Field

[0001] This invention relates to the technical field of power system automation, specifically to a method, system, device, and storage medium for detecting faults in distribution network operation based on topology reconfiguration. Background Technology

[0002] With the rapid development of smart grids, the importance of distribution network topology reconfiguration technology in improving the reliability of power grid operation and optimizing fault detection efficiency has become increasingly prominent. As the end link of the power system, the distribution network has a radial or ring-shaped open-loop topology structure, which includes a large number of sectional switches, tie switches and distributed power sources. Traditional methods determine the fault location by the timing of the operation of current and voltage protection devices, but it is difficult to adapt to topology changes.

[0003] Currently, the method of topology reconfiguration, which involves real-time detection of power changes in each line switch and automatic updating of the switch status in the network topology diagram, significantly improves intelligence and ease of operation without manual intervention. However, its detection of abnormal switch power is based on single-dimensional data analysis, lacking the ability to comprehensively process multi-source data, which may lead to inaccurate fault location. Furthermore, this method does not fully consider the dynamic interaction characteristics between nodes in the distribution network, potentially making efficient fault isolation and recovery difficult in complex topologies. These issues indicate that existing topology reconfiguration-based distribution network operation fault detection technologies still have certain shortcomings in terms of dynamic adaptability, multi-source data analysis capabilities, and fault location accuracy. Summary of the Invention

[0004] In view of the above-mentioned problems, this invention is proposed. Therefore, this invention provides a method, system, device, and storage medium for fault detection in distribution networks based on topology reconfiguration to solve the problems of insufficient fault location accuracy and fault detection efficiency, as well as poor adaptability to complex topologies.

[0005] To address the aforementioned technical problems, this invention provides the following technical solution: a method for detecting operational faults in a distribution network based on topology reconfiguration, comprising:

[0006] Obtain real-time operating parameters of the power grid and establish a three-dimensional node coordinate system based on the power grid topology to pinpoint fault locations;

[0007] The optimal power grid topology protection strategy is matched based on the real-time operating parameters of the power grid, and the operating status of the current power grid after matching is evaluated.

[0008] Based on the operational status assessment results, the power grid topology protection strategy is dynamically switched, and the fault locations before and after the power grid topology protection strategy switching are compared and analyzed to identify topology changes.

[0009] Based on the topology change identification results, and combined with the correlation between fault locations before and after the switchover, the network reconstruction direction is determined and a self-healing control strategy is executed.

[0010] As a preferred embodiment of the distribution network operation fault detection method based on topology reconfiguration described in this invention, the method includes: establishing a three-dimensional node coordinate system based on the power grid topology to pinpoint the fault location.

[0011] The three-dimensional node coordinate system maps each node in the power grid to a three-dimensional space, and each node has a unique coordinate value in the three-dimensional coordinate system; the location of the fault point in the three-dimensional coordinate system is determined by the positioning device.

[0012] As a preferred embodiment of the distribution network operation fault detection method based on topology reconfiguration described in this invention, the real-time operating parameters of the power grid include voltage fluctuations, current harmonics, and load distribution. Matching the optimal power grid topology protection strategy for the current power grid operation based on the real-time operating parameters includes: performing matching analysis on the current power grid using a multi-objective optimization algorithm to obtain the optimal power grid topology protection strategy for the current power grid operation; the optimization objectives of the multi-objective optimization algorithm include minimizing voltage deviation, minimizing harmonic distortion rate, balancing load distribution, and maximizing protection speed.

[0013] As a preferred embodiment of the distribution network operation fault detection method based on topology reconfiguration described in this invention, the evaluation of the current operation status of the power grid after matching includes: modeling the dynamic interaction characteristics of the power grid topology nodes for the power grid topology structure corresponding to the protection strategy of the optimal matching power grid topology structure, and constructing a dynamic interaction model of the power grid topology nodes.

[0014] A differential equation linearization model of the dynamic interaction of power grid topology nodes is adopted to obtain the eigenvalues ​​of the dynamic interaction model of power grid topology nodes at the power grid topology nodes, and the eigenvalues ​​are decomposed to obtain the real and imaginary parts of the eigenvalues.

[0015] The average coupling of the power grid topology nodes is calculated based on the active and reactive power at the nodes; the stability of the power grid topology loop is calculated based on the average coupling of the nodes and the eigenvalues ​​at the nodes.

[0016] If the stability of the power grid topology loop is not less than the preset evaluation threshold, the power grid is judged to be operating normally; if the stability of the power grid topology loop is less than the preset evaluation threshold, the power grid is judged to be operating abnormally.

[0017] As a preferred embodiment of the distribution network operation fault detection method based on topology reconfiguration described in this invention, the dynamic switching of the power grid topology protection strategy based on the operation status assessment results includes:

[0018] If the power grid is operating normally, the power grid topology protection strategy remains unchanged; if the power grid is operating abnormally, the power grid topology protection strategy is dynamically switched.

[0019] As a preferred embodiment of the distribution network operation fault detection method based on topology reconfiguration described in this invention, the method includes: comparing and analyzing the fault locations before and after the switching of the power grid topology protection strategy to identify topology changes, including:

[0020] The coordinates of the fault points before and after the power grid topology protection strategy switching are calibrated. The fault points before and after the switching are compared and analyzed. The analysis results include the disappearance of the fault points after the switching, the overlap of the fault points before and after the switching, and the non-overlap of the fault points before and after the switching.

[0021] When the analysis result shows that the fault location disappears after the switch, the identification of the topology change based on the protection strategy of the power grid topology after the switch is effective and the identification result is normal; when the analysis result shows that the fault locations before and after the switch overlap or do not overlap, the identification of the topology change based on the protection strategy of the power grid topology after the switch is invalid, the identification result is abnormal, and the correlation judgment of the fault locations before and after the switch is triggered.

[0022] As a preferred embodiment of the distribution network operation fault detection method based on topology reconfiguration described in this invention, the method includes: determining the network reconfiguration direction and executing a self-healing control strategy based on the topology change identification results and the correlation between fault locations before and after the switching, as well as the topology reconfiguration direction based on the correlation between fault locations before and after the switching.

[0023] The correlation is determined based on the time difference of the fault location before and after the switch, the spatial distance between the fault locations before and after the switch, the current similarity between the fault locations before and after the switch, and the impedance consistency between the fault locations before and after the switch.

[0024] When the correlation judgment result is greater than the preset threshold, the judgment result is strong correlation; when the correlation judgment result is not greater than the preset threshold, the judgment result is weak correlation.

[0025] When a topology anomaly is detected, the network reconstruction direction is determined based on the correlation judgment results, and a self-healing control strategy is executed.

[0026] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a distribution network operation fault detection system based on topology reconfiguration, comprising:

[0027] The data acquisition terminal operation module is used to acquire real-time operating parameters of the power grid and establish a three-dimensional node coordinate system based on the power grid topology to pinpoint fault locations.

[0028] The topology strategy matching module is used to match the optimal grid topology protection strategy for the current grid operation based on the real-time operating parameters of the grid.

[0029] The power grid operation status assessment module is used to assess the current operation status of the power grid after matching.

[0030] The topology dynamic switching module is used to dynamically switch the power grid topology protection strategy based on the operation status assessment results.

[0031] The control platform tracking and identification module is used to compare and analyze the fault locations before and after the power grid topology protection strategy switching in order to identify topology changes.

[0032] The identification result output module is used to determine the network reconstruction direction and execute self-healing control strategies based on the identification results of topology changes and the correlation between fault points before and after the switchover.

[0033] The present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, characterized in that the processor executes the computer program to implement the steps of the aforementioned method for detecting faults in the operation of a distribution network based on topology reconfiguration.

[0034] The present invention provides a computer-readable storage medium having a computer program stored thereon, characterized in that the computer program, when executed by a processor, implements the steps of the aforementioned method for detecting faults in a distribution network based on topology reconfiguration.

[0035] The beneficial effects of this invention are as follows: This invention ensures the timeliness of fault detection by real-time monitoring of power grid operating parameters through a data acquisition terminal; it matches power grid topology protection strategies based on real-time power grid operating parameters, avoiding the limitations of traditional fixed strategies and improving the accuracy and flexibility of fault detection; by real-time assessment of the power grid status, combined with comprehensive analysis by the topology analysis unit and fault diagnosis unit, it can accurately determine the health status of the power grid, providing strong support for fault risk prediction; it dynamically switches power grid topology protection strategies, flexibly adjusting protection strategies according to the power grid operating status, effectively reducing the risk of fault occurrence; furthermore, by comparing and analyzing fault locations before and after the switch, it achieves effective identification of topology changes, providing a reliable basis for network reconfiguration and self-healing control, and feeding back early warning commands and topology change identification results to user terminals in real time, enabling users to respond quickly and take corresponding measures, ensuring the safe and stable operation of the distribution network. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a schematic flowchart of a method for detecting faults in a distribution network based on topology reconfiguration, provided as an embodiment of the present invention.

[0038] Figure 2 This is a schematic diagram of the system structure of a distribution network operation fault detection system based on topology reconfiguration, provided as an embodiment of the present invention. Detailed Implementation

[0039] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0040] Example 1, referring to Figure 1 This is one embodiment of the present invention, which provides a method for detecting operational faults in a distribution network based on topology reconfiguration, comprising:

[0041] S100: Acquire real-time operating parameters of the power grid and establish a three-dimensional node coordinate system based on the power grid topology to pinpoint fault locations;

[0042] Furthermore, establishing a three-dimensional node coordinate system based on the power grid topology to pinpoint fault locations includes:

[0043] The three-dimensional node coordinate system maps each node in the power grid to a three-dimensional space, and each node has a unique coordinate value in the three-dimensional coordinate system; the location of the fault point in the three-dimensional coordinate system is determined by the positioning device.

[0044] S200: Match the optimal grid topology protection strategy for the current grid operation based on the real-time operating parameters of the grid, and evaluate the operating status of the current grid after matching;

[0045] Furthermore, real-time power grid operating parameters include voltage fluctuations, current harmonics, and load distribution. Protection strategies that match the optimal power grid topology based on these real-time operating parameters include:

[0046] A multi-objective optimization algorithm is used to perform matching analysis on the current power grid to obtain the optimal power grid topology protection strategy for the current power grid operation. The optimization objectives of the multi-objective optimization algorithm include minimizing voltage deviation, minimizing harmonic distortion rate, balancing load distribution, and maximizing protection speed.

[0047] Specifically, the multi-objective optimization algorithm is expressed as:

[0048]

[0049] in, Indicates node voltage. Indicates the rated voltage. This represents the total harmonic distortion rate of the node current. This represents the maximum value of the node's line load rate. This represents the minimum value of the node's line load rate. Indicates the time to clear the fault. Indicates the total number of nodes in the power grid topology. in Indicates the node number. The function that minimizes the voltage deviation is the objective function. The function that optimizes to minimize the harmonic distortion rate. The function that optimizes the load distribution is equitable. The function that optimizes to maximize the protection of speed.

[0050] Furthermore, the evaluation of the current power grid operation status after matching includes: modeling the dynamic interaction characteristics of the power grid topology nodes for the power grid topology protection strategy corresponding to the optimal matching power grid topology structure, and constructing a dynamic interaction model of the power grid topology nodes;

[0051] A differential equation linearization model of the dynamic interaction of power grid topology nodes is adopted to obtain the eigenvalues ​​of the dynamic interaction model of power grid topology nodes at the power grid topology nodes, and the eigenvalues ​​are decomposed to obtain the real and imaginary parts of the eigenvalues.

[0052] The average coupling of the power grid topology nodes is calculated based on the active and reactive power at the nodes; the stability of the power grid topology loop is calculated based on the average coupling of the nodes and the eigenvalues ​​at the nodes.

[0053] Specifically, the formula for calculating the average coupling of nodes in the power grid topology is as follows:

[0054]

[0055] in, This represents the average coupling of nodes in the power grid topology. Indicates the node number of the power grid topology, and , and They represent the first The active and reactive power of each node. and They represent the first The active and reactive power of each node. It is a partial derivative.

[0056] Specifically, the stability of the power grid topology loop is calculated based on the average coupling of the nodes and the eigenvalues ​​at the nodes. The calculation formula is as follows:

[0057]

[0058] in, Indicates the stability of the power grid topology loop. This represents the value corresponding to the real part of the eigenvalue of a node in the power grid topology. This represents the value corresponding to the imaginary part of the eigenvalues ​​of a node in the power grid topology. This represents the average coupling of nodes in the power grid topology. This represents the maximum coupling between nodes in the power grid topology. , These are weighting coefficients used to adjust the influence of the nodal eigenvalues ​​and average coupling components of the power grid topology on the calculation of the power grid topology loop stability. .

[0059] Furthermore, if the stability of the power grid topology loop is not less than the preset evaluation threshold, the power grid is judged to be operating normally; if the stability of the power grid topology loop is less than the preset evaluation threshold, the power grid is judged to be operating abnormally.

[0060] It should be noted that in this embodiment, the preset evaluation threshold can be set between 0.5 and 0.7 under normal circumstances. If it is composed of multiple interconnected regional power grids, the scale is huge and the stability requirements are extremely high, the preset evaluation threshold will be set above 0.8.

[0061] Furthermore, when the power grid is in an abnormal operating state, insulation impedance detection and transient overvoltage analysis are performed based on the calibrated fault location data. The severity of the fault is comprehensively assessed by combining the results of the two analyses. When the severity of the fault exceeds the preset topology reconfiguration judgment threshold, the network reconfiguration direction is determined by combining the correlation between the fault locations before and after the switchover, and a self-healing control strategy is executed.

[0062] It should be noted that the preset topology reconstruction judgment threshold in this embodiment can be set between 0.7 and 0.9.

[0063] Furthermore, insulation impedance detection determines the presence of an insulation fault by measuring the insulation resistance value at the fault location, while transient overvoltage analysis identifies the fault type and location by analyzing the transient overvoltage waveforms in the power grid.

[0064] Specifically, an insulation resistance tester is used to apply a DC high voltage to the fault location. By measuring the leakage current under the applied voltage, the insulation resistance value is calculated according to Ohm's law. If the measured insulation resistance value is much lower than the standard value, it can be determined that there is an insulation fault.

[0065] By collecting waveform data of transient overvoltages during power grid operation in real time, fault types can be identified.

[0066] When the fault type is a single-phase ground fault, the transient overvoltage waveform shows a sudden increase in single-phase voltage and a slight decrease in the voltage of the other two phases; when the fault type is a phase-to-phase short-circuit fault, the voltage of the faulty phase will drop sharply.

[0067] By analyzing the arrival time difference of transient waveforms at multiple measuring points, and combining this with the length of the power grid line and the wave velocity, the location of the fault point can be calculated. The calculation formula is as follows:

[0068]

[0069] in, The distance from the fault point to the measuring point. For wave speed, The time difference between the arrival times of the waveforms at the two measuring points;

[0070] If an insulation fault is determined to exist, and both types of faults are present, then the severity of the fault is higher than the overall assessment of the severity of the fault.

[0071] Specifically, when the power grid operating status is assessed as abnormal, the numerical calculation process for the severity of the fault includes steps A1 to A3:

[0072] Step A1: Collect the actual insulation resistance at the fault location using an insulation resistance tester. At the same time, retrieve the standard value of the insulation resistance of the power grid node of this model under standard operating conditions. Calculate the ratio between the actual insulation resistance and the standard insulation resistance. If the actual value is greater than or equal to the standard value, the ratio is recorded as 1, indicating that the insulation performance is normal. If the actual value is less than the standard value, the actual ratio is used directly. The smaller the ratio, the more serious the insulation fault.

[0073] Step A2: Real-time acquisition of transient overvoltage amplitude at the fault location, retrieval of the grid rated voltage and calculation of the ratio of transient overvoltage amplitude to rated voltage, and determination of fault type weight based on fault diagnosis results, wherein the weight of phase-to-phase short circuit fault is set to 1.0, the weight of single-phase ground fault is set to 0.6, and the weight is set to 0 when there is no such fault, and the transient overvoltage ratio is multiplied by the corresponding fault type weight to obtain the transient overvoltage abnormal correlation value;

[0074] Step A3: Based on the requirements for safe operation of the distribution network, the weights of insulation status and transient overvoltage in the fault severity assessment are determined using the analytic hierarchy process (AHP) and the Delphi method. The insulation status accounts for 40% of the weight, and the transient overvoltage accounts for 60%. First, the insulation resistance ratio is subtracted from 1 to obtain the degree of impact of the insulation fault. Then, this degree of impact is multiplied by the corresponding weight, and the transient overvoltage anomaly correlation value is multiplied by its corresponding weight to obtain a quantitative value of the fault severity. This value ranges from 0 to 1, with a larger value indicating a higher degree of fault severity. It can be directly compared with a preset topology reconfiguration judgment threshold. When the quantitative value is higher than the preset topology reconfiguration judgment threshold, the subsequent network reconfiguration direction determination and self-healing control strategy execution process is immediately triggered.

[0075] S300: Based on the operational status assessment results, dynamically switch the power grid topology protection strategy and compare and analyze the fault locations before and after the power grid topology protection strategy switch to identify topology changes.

[0076] Furthermore, the dynamic switching of power grid topology protection strategies based on operational status assessment results includes:

[0077] If the power grid is operating normally, the power grid topology protection strategy remains unchanged; if the power grid is operating abnormally, the power grid topology protection strategy is dynamically switched.

[0078] Specifically, the process of dynamically switching power grid topology protection strategies includes steps B1 to B4:

[0079] Step B1: Real-time acquisition of operating data such as voltage, current, active power and power flow direction of each node in the distribution network, construction of a static topology model in combination with the power grid topology, and dynamic updating of the real-time topology based on the real-time operating data, while continuously evaluating the stability and operating status of the power grid topology loop through the topology analysis unit;

[0080] Step B2: When the evaluation result indicates normal operation, the system maintains the current basic protection strategy, which focuses on ensuring stable grid operation and minimizing energy consumption. Once the evaluation detects an abnormal grid operation, the system immediately initiates the strategy switching process. Through a preset multi-objective optimization algorithm, combined with real-time topology, fault location information, fault type, and severity, the system matches the optimal adaptation strategy from the preset protection strategy library. The strategy library covers dedicated protection schemes for different topologies, fault types, and distributed power source access scenarios, including directional overcurrent protection, fast-acting intelligent distributed protection, and adaptive overcurrent threshold setting.

[0081] Step B3: During the switching execution phase, real-time coordination between the main station and terminal equipment such as boundary switches and distributed power controllers is achieved through fiber optic or 5G communication. First, the original protection strategy is blocked, and then the action threshold, timing coordination logic and blocking conditions of each protection device are adaptively adjusted according to the matched optimal strategy. If distributed power or node areas containing energy storage are involved, the protection settings and power flow control logic of the corresponding areas need to be adjusted synchronously to ensure that there are no false or failed operations during the switching process.

[0082] Step B4: After the switch is completed, the adaptability of the new protection strategy is verified by continuously monitoring the power grid operation data and the changes in the fault location. If the topology structure is detected to change again, steps B1 to B3 are repeated to perform a new round of dynamic matching and switching of the protection strategy, so as to always ensure that the protection strategy is accurately adapted to the real-time operating status and topology of the power grid.

[0083] Furthermore, a comparative analysis of fault locations before and after the switching of power grid topology protection strategies is conducted to identify topology changes, including:

[0084] The coordinates of the fault points before and after the power grid topology protection strategy switching are calibrated. The fault points before and after the switching are compared and analyzed. The analysis results include the disappearance of the fault points after the switching, the overlap of the fault points before and after the switching, and the non-overlap of the fault points before and after the switching.

[0085] When the analysis result shows that the fault location disappears after the switch, the identification of the topology change based on the protection strategy of the power grid topology after the switch is effective and the identification result is normal; when the analysis result shows that the fault locations before and after the switch overlap or do not overlap, the identification of the topology change based on the protection strategy of the power grid topology after the switch is invalid, the identification result is abnormal, and the correlation judgment of the fault locations before and after the switch is triggered.

[0086] S400: Based on the topology change identification results, combined with the correlation of fault points before and after the switch, determine the network reconstruction direction and execute the self-healing control strategy.

[0087] Furthermore, based on the topology change identification results, and combined with the correlation between fault locations before and after the switchover, the network reconstruction direction is determined and self-healing control strategies are implemented, including:

[0088] The correlation is determined based on the time difference of the fault location before and after the switch, the spatial distance between the fault locations before and after the switch, the current similarity between the fault locations before and after the switch, and the impedance consistency between the fault locations before and after the switch.

[0089] Specifically, the formula for determining relevance is as follows:

[0090]

[0091] in, This indicates the result of the correlation judgment. This indicates the time difference between when the fault occurred at the fault location before and after the switchover. This indicates the spatial distance between the fault locations before and after the switchover. This indicates the similarity of the current at the fault location before and after the switching. This indicates the consistency of impedance at the fault location before and after the switchover. and This indicates the preset maximum time threshold and maximum distance threshold. , , as well as These represent the weights.

[0092] It should be noted that in this implementation, the maximum time threshold can be set to 10ms-20ms; the maximum distance threshold can be set to 10km-15km.

[0093] Furthermore, when the correlation judgment result is greater than the preset threshold, the judgment result is a strong correlation; when the correlation judgment result is not greater than the preset threshold, the judgment result is a weak correlation.

[0094] When a topology anomaly is detected, the network reconstruction direction is determined based on the correlation judgment results and a self-healing control strategy is executed.

[0095] Specifically, if the correlation judgment result is determined to be strong correlation, it indicates that there is a direct correlation between the fault points before and after the switchover. In this case, the network reconstruction direction is fault branch isolation and load transfer. The self-healing control strategy is to prioritize locating the topology branch where the fault point is located, determine the fault line switch that needs to be disconnected and the tie switch that needs to be closed, and transfer the load of the fault branch to the adjacent healthy topology branch to avoid load interruption.

[0096] If the correlation judgment result is weak correlation, it means that there is no direct correlation between the fault points before and after the switch. In this case, the network reconstruction direction is global topology optimization, and the self-healing control strategy is to analyze the load distribution and voltage level of the overall distribution network topology and prioritize adjusting the topology structure of the area where the weakly correlated fault points are located, such as adding tie switches and optimizing the distributed power supply access nodes.

[0097] It should be noted that in this embodiment, the preset threshold can be set to 0.7; for example, when the preset threshold is 0.7, if If the correlation is strong, then the result is a strong correlation; otherwise, if If the correlation is weak, the result is a weak association.

[0098] In this embodiment, it is important to note that the main difference between this embodiment and the prior art lies in the fact that the present invention ensures the timeliness of fault detection by real-time monitoring of power grid operating parameters through a data acquisition terminal; it matches the power grid topology protection strategy according to the real-time power grid operating parameters, avoiding the limitations of traditional fixed strategies and improving the accuracy and flexibility of fault detection; by conducting real-time assessment of the power grid status, combined with comprehensive analysis of topology analysis and fault diagnosis, it can accurately determine the health status of the power grid, providing strong support for fault risk prediction; it dynamically switches the power grid topology protection strategy, flexibly adjusting the protection strategy according to the power grid operating status, effectively reducing the risk of fault occurrence; by comparing and analyzing the fault locations before and after the switch, it achieves effective identification of topology changes, providing a reliable basis for network reconstruction and self-healing control; and it feeds back early warning commands and topology change identification results to the user terminal in real time, enabling users to respond quickly and take corresponding measures, ensuring the safe and stable operation of the distribution network.

[0099] Example 2, refer to Figure 2 As one embodiment of the present invention, this embodiment provides a distribution network operation fault detection system based on topology reconfiguration, comprising:

[0100] The data acquisition terminal operation module is used to acquire real-time operating parameters of the power grid and establish a three-dimensional node coordinate system based on the power grid topology to pinpoint fault locations.

[0101] The topology strategy matching module is used to match the optimal grid topology protection strategy for the current grid operation based on the real-time operating parameters of the grid.

[0102] The power grid operation status assessment module is used to assess the current operation status of the power grid after matching.

[0103] The topology dynamic switching module is used to dynamically switch the power grid topology protection strategy based on the operation status assessment results.

[0104] The control platform tracking and identification module is used to compare and analyze the fault locations before and after the power grid topology protection strategy switching in order to identify topology changes.

[0105] The identification result output module is used to determine the network reconstruction direction and execute self-healing control strategies based on the identification results of topology changes and the correlation between fault points before and after the switchover.

[0106] Furthermore, the power grid operation status assessment module also includes a topology analysis unit and a fault diagnosis unit;

[0107] The topology analysis unit is used to analyze the coupling relationship between nodes after the power grid topology is matched, model the dynamic interaction characteristics of the power grid topology nodes, analyze the stability of the power grid topology loop through eigenvalue decomposition, and evaluate the power grid operating status based on the stability of the power grid topology loop.

[0108] The fault diagnosis unit is used to diagnose faults at the fault locations calibrated in the data acquisition terminal operation module after the power grid topology is matched.

[0109] Furthermore, the control platform tracking and identification module also includes a fault location comparison and analysis unit and a topology change identification unit;

[0110] The fault location comparison and analysis unit is used to track the coordinates of the fault location through the positioning device after the power grid topology protection strategy is switched, and to compare and analyze the fault locations before and after the switch.

[0111] The topology change identification unit is used to identify the effectiveness of topology changes based on the comparison and analysis results of fault locations before and after the switchover.

[0112] In an optional embodiment, the data acquisition terminal collects grid operating parameters in real time through intelligent sensing devices deployed at key nodes of the distribution network. The intelligent sensing devices include voltage sensors, current sensors, and load sensors. The sensors can monitor voltage fluctuations, current harmonics, and load distribution in the grid in real time. By uploading the data collected by these sensors to the data acquisition terminal operating module, comprehensive monitoring of the grid operating status can be achieved.

[0113] The data acquisition terminal establishes a three-dimensional node coordinate system based on the power grid topology. The three-dimensional node coordinate system maps each node in the power grid to a three-dimensional space. Each node has a unique coordinate value in the three-dimensional coordinate system. The fault location in the three-dimensional coordinate system is accurately calibrated by the positioning device.

[0114] In an optional embodiment, the topology strategy matching module performs matching analysis based on the power grid operating parameters collected by the data acquisition terminal operation module and a multi-objective optimization algorithm, and outputs a matched power grid topology protection strategy.

[0115] In an optional embodiment, after the power grid topology is matched, the coupling relationship between nodes is analyzed by a dynamic topology analysis unit, the dynamic interaction characteristics of the power grid topology nodes are modeled, the stability of the power grid topology loop is analyzed by eigenvalue decomposition, and the power grid operating status is evaluated based on the stability of the power grid topology loop.

[0116] In this embodiment, the specific content of the topology analysis unit is as follows:

[0117] Based on the active and reactive power at the nodes, the average coupling of the power grid topology nodes is analyzed;

[0118] The dynamic interaction characteristics of power grid topology nodes are modeled. The dynamic interaction model of power grid topology nodes is linearized by differential equations. The eigenvalues ​​of the dynamic interaction model of power grid topology nodes at the power grid topology nodes are obtained, and the eigenvalues ​​are decomposed to obtain the real and imaginary parts of the eigenvalues.

[0119] The stability of the power grid topology loop is calculated based on the average coupling of the power grid topology nodes and the characteristic values ​​at the power grid topology nodes. The power grid operating status is then assessed based on the stability of the power grid topology loop: when the stability of the power grid topology loop is greater than or equal to the preset assessment threshold, the power grid operating status is judged to be normal; conversely, when the stability of the power grid topology loop is less than the preset assessment threshold, the power grid operating status is judged to be abnormal.

[0120] In an optional embodiment, after the power grid topology is matched, the fault diagnosis unit performs fault diagnosis on the fault points calibrated in the data acquisition terminal operation module.

[0121] In this embodiment, the specific contents of the fault diagnosis unit are as follows:

[0122] Based on the fault location data provided by the data acquisition terminal's operation module, the fault diagnosis unit uses insulation impedance detection and transient overvoltage analysis techniques to accurately diagnose faults in the power grid.

[0123] Insulation impedance detection determines the presence of an insulation fault by measuring the insulation resistance value at the fault location. Transient overvoltage analysis identifies the fault type and location by analyzing the transient overvoltage waveform in the power grid. An insulation resistance tester applies a DC high voltage to the fault location, measures the leakage current under the applied voltage, and calculates the insulation resistance value based on Ohm's law. If the measured insulation resistance value is much lower than the standard value, an insulation fault can be determined.

[0124] The fault diagnosis unit combines the detection results of insulation impedance and transient overvoltage to comprehensively assess the severity of the fault. When the severity of the fault exceeds the topology reconstruction judgment threshold, it sends an early warning message to the identification result output module.

[0125] In an optional embodiment, the topology dynamic switching module dynamically switches the power grid topology protection strategy based on the power grid operation status assessment results:

[0126] If the power grid is operating normally, the power grid topology protection strategy remains unchanged; if the power grid is operating abnormally, the power grid topology protection strategy is dynamically switched.

[0127] In an optional embodiment, after switching the power grid topology protection strategy, the fault location comparison and analysis unit tracks the coordinates of the fault location through a positioning device and compares and analyzes the fault locations before and after the switch. The analysis results are: the fault location disappears after the switch, the fault locations before and after the switch overlap, and the fault locations before and after the switch do not overlap.

[0128] In an optional embodiment, the topology change identification unit identifies the validity of the topology change based on the comparison and analysis results of fault locations before and after the switchover:

[0129] When the fault location disappears after the switch, the topology change identification result is: the topology change based on the grid topology protection strategy after the switch is effective, and the identification result is normal.

[0130] When the fault locations before and after the switchover coincide, the topology change identification result is: the topology change based on the grid topology protection strategy after the switchover is invalid, the identification result is abnormal, and the correlation between the fault locations before and after the switchover is determined.

[0131] When the fault locations before and after the switch do not overlap, the topology change identification result is: the topology change based on the grid topology protection strategy after the switch is invalid, the identification result is abnormal, and the correlation between the fault locations before and after the switch is determined.

[0132] In an optional embodiment, the identification result output module receives the early warning information sent by the fault diagnosis unit, generates a fault location early warning instruction, and outputs the early warning instruction and the topology change identification result to the user terminal. The user terminal performs early warning operations according to the early warning instruction, and when a topology anomaly is detected, it determines the network reconstruction direction based on the correlation between the fault locations before and after the switch and executes a self-healing control strategy.

[0133] It should be noted that the main difference between this invention and the prior art lies in the following: this embodiment includes a data acquisition terminal operation module, a topology strategy matching module, a power grid operation status assessment module, a topology dynamic switching module, a control platform tracking and identification module, and an identification result output module. The data acquisition terminal monitors power grid operation parameters in real time to ensure the timeliness of fault detection; it matches power grid topology protection strategies based on real-time power grid operation parameters, avoiding the limitations of traditional fixed strategies and improving the accuracy and flexibility of fault detection; the power grid operation status assessment module performs real-time assessment of the power grid status, and combined with the comprehensive analysis of the topology analysis unit and the fault diagnosis unit, it can accurately determine the health status of the power grid, providing strong support for fault risk prediction; the dynamic switching of power grid topology protection strategies flexibly adjusts the protection strategy according to the power grid operation status, effectively reducing the risk of fault occurrence; the control platform tracking and identification module effectively identifies topology changes by comparing and analyzing fault locations before and after the switching, providing a reliable basis for network reconfiguration and self-healing control; and the identification result output module feeds back early warning commands and topology change identification results to the user terminal in real time, enabling users to respond quickly and take corresponding measures, ensuring the safe and stable operation of the distribution network.

[0134] Example 3 is an embodiment of the present invention, which differs from the previous two embodiments in that:

[0135] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0136] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-including system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0137] More specific examples (a non-exhaustive list) of computer-readable media include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which programs can be printed, because programs can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0138] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0139] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for detecting operational faults in a distribution network based on topology reconfiguration, characterized in that, include: Acquiring real-time operating parameters of the power grid and establishing a three-dimensional node coordinate system based on the power grid topology to pinpoint fault locations includes: the three-dimensional node coordinate system maps each node in the power grid to a three-dimensional space, with each node having a unique coordinate value in the three-dimensional coordinate system; and using a positioning device to pinpoint the location of the fault location in the three-dimensional coordinate system. The optimal grid topology protection strategy is matched to the current grid operation based on the real-time grid operating parameters, and the operating status of the current grid after matching is evaluated. The real-time grid operating parameters include voltage fluctuations, current harmonics, and load distribution. The optimal grid topology protection strategy matched to the current grid operation based on the real-time grid operating parameters includes: A multi-objective optimization algorithm is used to perform matching analysis on the current power grid to obtain the optimal power grid topology protection strategy for the current power grid operation. The optimization objectives of the multi-objective optimization algorithm include minimizing voltage deviation, minimizing harmonic distortion rate, balancing load distribution, and maximizing protection speed. The evaluation of the current power grid operation status after matching includes: modeling the dynamic interaction characteristics of the power grid topology nodes for the power grid topology protection strategy corresponding to the optimal matching power grid topology structure, and constructing a dynamic interaction model of the power grid topology nodes; A differential equation linearization model of the dynamic interaction of power grid topology nodes is adopted to obtain the eigenvalues ​​of the dynamic interaction model of power grid topology nodes at the power grid topology nodes, and the eigenvalues ​​are decomposed to obtain the real and imaginary parts of the eigenvalues. The average coupling of the power grid topology nodes is calculated based on the active and reactive power at the nodes; the stability of the power grid topology loop is calculated based on the average coupling of the nodes and the eigenvalues ​​at the nodes. If the stability of the power grid topology loop is not less than the preset evaluation threshold, the power grid is judged to be in normal operation; if the stability of the power grid topology loop is less than the preset evaluation threshold, the power grid is judged to be in abnormal operation. Based on the operational status assessment results, the power grid topology protection strategy is dynamically switched, and the fault locations before and after the power grid topology protection strategy switching are compared and analyzed to identify topology changes. Based on the topology change identification results, and combined with the correlation between fault locations before and after the switchover, the network reconstruction direction is determined and a self-healing control strategy is executed.

2. The method for detecting operational faults in a distribution network based on topology reconfiguration as described in claim 1, characterized in that, Dynamic switching of power grid topology protection strategies based on operational status assessment results includes: If the power grid is operating normally, the power grid topology protection strategy remains unchanged; if the power grid is operating abnormally, the power grid topology protection strategy is dynamically switched.

3. The method for detecting operational faults in a distribution network based on topology reconfiguration as described in claim 2, characterized in that, A comparative analysis of fault locations before and after the switching of power grid topology protection strategies is conducted to identify topology changes, including: The coordinates of the fault points before and after the power grid topology protection strategy switching are calibrated. The fault points before and after the switching are compared and analyzed. The analysis results include the disappearance of the fault points after the switching, the overlap of the fault points before and after the switching, and the non-overlap of the fault points before and after the switching. When the analysis result shows that the fault location disappears after the switch, the identification of the topology change based on the protection strategy of the power grid topology after the switch is effective and the identification result is normal; when the analysis result shows that the fault locations before and after the switch overlap or do not overlap, the identification of the topology change based on the protection strategy of the power grid topology after the switch is invalid, the identification result is abnormal, and the correlation judgment of the fault locations before and after the switch is triggered.

4. The method for detecting operational faults in a distribution network based on topology reconfiguration as described in claim 3, characterized in that, Based on the topology change identification results, and combined with the correlation between fault locations before and after the handover, the network reconstruction direction is determined and a self-healing control strategy is implemented, including: The correlation is determined based on the time difference of the fault location before and after the switch, the spatial distance between the fault locations before and after the switch, the current similarity between the fault locations before and after the switch, and the impedance consistency between the fault locations before and after the switch. When the correlation judgment result is greater than the preset threshold, the judgment result is strong correlation; when the correlation judgment result is not greater than the preset threshold, the judgment result is weak correlation. When a topology anomaly is detected, the network reconstruction direction is determined based on the correlation judgment results and a self-healing control strategy is executed.

5. A distribution network operation fault detection system based on topology reconfiguration, employing the distribution network operation fault detection method based on topology reconfiguration as described in any one of claims 1 to 4, characterized in that, include: The data acquisition terminal operation module is used to acquire real-time operating parameters of the power grid and establish a three-dimensional node coordinate system based on the power grid topology to pinpoint fault locations. The topology strategy matching module is used to match the optimal grid topology protection strategy for the current grid operation based on the real-time operating parameters of the grid. The power grid operation status assessment module is used to assess the current operation status of the power grid after matching. The topology dynamic switching module is used to dynamically switch the power grid topology protection strategy based on the operation status assessment results. The control platform tracking and identification module is used to compare and analyze the fault locations before and after the power grid topology protection strategy switching in order to identify topology changes. The identification result output module is used to determine the network reconstruction direction and execute self-healing control strategies based on the identification results of topology changes and the correlation between fault points before and after the switchover.

6. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the distribution network operation fault detection method based on topology reconfiguration as described in any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the distribution network operation fault detection method based on topology reconfiguration as described in any one of claims 1 to 4.

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