Distribution network overhead line fault self-recovery method, system, equipment and medium

Abstract

The invention discloses a distribution network overhead line fault self-healing method, system and device and a medium, and belongs to the technical field of power system fault self-healing, and the method comprises the steps: laying a synchronous phasor measurement unit, and generating a unified phasor reference through cloud edge cooperative calculation; the edge coordination engine calculates the load flow change after loop closing by means of a unified phasor reference and an instantaneous topological state to form an action sequence; the local controller obtains a coordination coefficient and controls the pre-compensation of the flexible interconnection device and the closing time of the section switch; pushing the temperature rise prediction value to a wire thermal model; and the edge controller circularly and adaptively corrects the compensation parameter of the flexible interconnection device, and writes the event into the self-healing knowledge base. According to the invention, automation and intelligentization of fault self-healing are realized, the efficiency of fault self-healing is significantly improved, and long-term stable operation of the power distribution network after fault recovery is ensured; and through intelligent and adaptive design, a brand new technical path is provided for long-term reliable operation of the distribution network.

Description

Technical Field

[0001] This invention relates to the field of power system fault self-healing technology, specifically to a method, system, equipment, and medium for fault self-healing of overhead distribution lines. Background Technology

[0002] In most urban and mountainous power distribution networks, overhead lines typically operate in an open-loop manner. Upon encountering a fault, the faulty section is quickly isolated, and a new power supply path is reconstructed to minimize outage time. In this process, traditional sectionalizing switches handle electrical isolation or loop closing, while flexible interconnection devices maintain power flow and voltage stability in the new topology through rapid reactive power and harmonic compensation. With the large-scale integration of distributed photovoltaic, energy storage, and electric vehicle charging facilities, the direction and amplitude of power flow in lines fluctuate frequently. The high impedance and long loops of overhead conductors make instantaneous voltage and phase imbalances more likely. When the flexible interconnection devices and mechanical switches operate out of sync, the voltage vector at the moment of loop closing cannot be precisely aligned. Harmonic currents flow back along high-impedance paths and superimpose, causing a rapid increase in conductor temperature and increased insulation electric field stress. In severe cases, this can trigger secondary tripping or even fires, posing new challenges to power supply reliability and equipment lifespan.

[0003] However, flexible interconnection devices and traditional sectionalizing switches rely on different measurement and control cycles and lack a unified real-time phasor reference, making it difficult for the two types of devices to achieve coordinated synchronization when reconstructing the loop after fault isolation. Secondly, how is the risk triggered? After the self-healing algorithm issues a reconstruction command, the switch usually closes first, and the flexible interconnection device intervenes to compensate later. The brief time misalignment causes the new power supply circuit to experience a double change in voltage amplitude and phase, and harmonics and unbalanced currents are amplified on long-distance overhead conductors. Finally, how does the risk spread? The skin effect and proximity effect generated by harmonic currents cause local heating of the conductor, accelerate insulation aging, and may interfere with protection criteria. Flexible interconnection devices are prone to misjudging the fault as a second failure and disconnecting the load, forming a vicious chain of self-healing cycle failure. Summary of the Invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the technical problem solved by this invention is: how to solve the problem that flexible interconnection devices and traditional segmented switches rely on different measurement and control cycles and lack a unified real-time phasor reference, making it difficult for the two types of devices to achieve coordinated synchronization when reconstructing the loop after fault isolation.

[0006] To address the aforementioned technical problems, this invention provides the following technical solution: a self-healing method for overhead distribution line faults, comprising: deploying synchronous phasor measurement units on both sides of a flexible interconnection device and a key sectionalizing switch to continuously collect voltage and current phasors; generating a unified phasor reference through cloud-edge collaborative calculation and broadcasting it to a local controller; the edge coordination engine, based on the unified phasor reference and instantaneous topology state, calculating the power flow changes after loop closure to form an action sequence, and simultaneously writing it into the trigger queues of the flexible interconnection device and the sectionalizing switch; the local controller performing membership reasoning on phasor synchronization deviation and harmonic-thermal risk to obtain a coordination coefficient, and controlling the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and a preset threshold; the line harmonic sensor continuously uploading spectrum data; the self-tuning filter in the flexible interconnection device suppressing high-order components in real time according to the harmonic distribution, and pushing the temperature rise prediction value to the conductor thermal model; the edge controller cyclically comparing the conductor thermal model, the synchronous phase-locked loop consistency index, and the protection action record, adaptively correcting the compensation parameters of the flexible interconnection device, and writing the event into the self-healing knowledge base.

[0007] As a preferred embodiment of the self-healing method for overhead power line faults in the present invention, the method of deploying synchronous phasor measurement units on both sides of the flexible interconnection device and the key sectionalizing switch to continuously collect voltage and current phasors, generating a unified phasor reference through cloud-edge collaborative computing, and broadcasting it to the local controller includes: installing synchronous phasor measurement units on both sides of the flexible interconnection device and the key sectionalizing switch to acquire voltage and current phasors and transmitting them to the edge computing node and the cloud computing platform through a high-speed communication network; the edge computing node preprocessing the received data and uploading it to the cloud computing platform; the cloud computing platform calibrating the data from each synchronous phasor measurement unit based on a time synchronization algorithm to generate a unified phasor reference; and distributing the unified phasor reference to the local controller via broadcast.

[0008] As a preferred embodiment of the self-healing method for overhead line faults in a distribution network as described in this invention, the edge coordination engine, relying on a unified phasor reference and instantaneous topology state, calculates the power flow changes after loop closure and forms an action sequence, which is simultaneously written into the trigger queues of the flexible interconnection device and the sectionalizing switch. This includes: the edge coordination engine receiving a unified phasor reference and the current instantaneous topology state from the synchronous phasor measurement unit; the edge coordination engine using a power flow calculation algorithm to predict the power flow changes under loop closure operation based on the unified phasor reference and instantaneous topology state, identifying the power change trends of key branches; constructing an action sequence comprising three stages: compensation, closing, and tracking, and determining the execution timing of each stage; writing the action sequence into the trigger queues of the flexible interconnection device and the sectionalizing switch, and setting time markers to ensure that each control action is executed in a predetermined order.

[0009] As a preferred embodiment of the self-healing method for overhead power line faults in the present invention, the local controller obtains a coordination coefficient by performing membership reasoning on phasor synchronization deviation and harmonic-thermal risk, and controls the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and a preset threshold. This includes: the local controller acquiring real-time voltage phasors and comparing them with a unified phasor reference to calculate the phase angle difference to quantify the phasor synchronization deviation; collecting current harmonic current data and calculating its impact on conductor temperature rise to quantify the harmonic-thermal risk; using the phasor synchronization deviation and harmonic-thermal risk as inputs to generate a coordination coefficient through fuzzy reasoning; and comparing the coordination coefficient with a preset threshold to control the compensation operation of the flexible interconnection device and the closing timing of the sectionalizing switch.

[0010] As a preferred embodiment of the self-healing method for overhead power line faults in the present invention, the step of controlling the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold includes: the coordination coefficient is generated by taking phasor synchronization deviation and harmonic-thermal risk as joint inputs, and then going through a three-stage process of fuzzification, fuzzy inference and defuzzification in fuzzy logic; the fuzzy rule set is preset based on historical operating experience; and the defuzzification process uses the centroid method for output calculation.

[0011] This preferred scheme uses phasor synchronization deviation and harmonic-thermal risk as joint inputs to a fuzzy logic system. It generates coordination coefficients through a three-level processing flow of fuzzification, inference, and defuzzification, effectively integrating multi-dimensional information under uncertain environments to improve the stability and accuracy of closed-loop control decisions. The fuzzy rule set can be empirically set based on historical operating data to adapt to complex distribution network changes. The centroid method is used for defuzzification, resulting in a smoother distribution and more sensitive response of the output coordination coefficient values, providing a more reasonable basis for action judgments of flexible interconnection devices and sectionalizing switches.

[0012] As a preferred embodiment of the self-healing method for faults in overhead distribution lines according to the present invention, the method includes: the line harmonic sensor continuously uploading spectrum data; the self-tuning filter in the flexible interconnection device suppressing high-order components in real time according to the harmonic distribution; and pushing the predicted temperature rise value to the conductor thermal model. This includes: continuously collecting the spectrum data of branch currents through harmonic sensors installed at key nodes of the overhead distribution line and uploading it to the flexible interconnection device to reflect the harmonic current distribution in real time; the self-tuning filter configured in the flexible interconnection device dynamically adjusting the filtering parameters according to the spectrum data to generate compensation current to offset high-order harmonic components exceeding the threshold; the flexible interconnection device combining the spectrum data and the fundamental component of the branch current to predict the conductor temperature rise trend based on the conductor thermal model, forming a thermal state estimate for the future time period; when the predicted temperature rise exceeds the safety threshold, the flexible interconnection device triggers a feedforward control mechanism to adjust the active power regulation and reactive power compensation to control the branch power flow, thereby reducing the heat generation power and maintaining the conductor temperature within a set range.

[0013] This preferred solution continuously uploads spectrum data via harmonic sensors and dynamically generates compensation current using a self-tuning filter to suppress higher-order harmonics, enabling real-time response control to harmonic interference. Simultaneously, the flexible interconnect device constructs a conductor thermal model based on spectrum and fundamental frequency information to predict temperature rise. Before the temperature rise exceeds a threshold, it proactively adjusts active and reactive power compensation through a feedforward control mechanism, effectively preventing conductor overheating. These mechanisms form a closed-loop chain from harmonic monitoring and thermal risk prediction to power flow regulation, enhancing the flexible interconnect device's overall ability to handle thermal-electrical collaborative risks during fault self-healing.

[0014] As a preferred embodiment of the self-healing method for overhead line faults in a distribution network as described in this invention, the edge controller cyclically compares the conductor thermal model, the synchronous phase-locked loop consistency index, and the protection action records, adaptively corrects the compensation parameters of the flexible interconnection device, and writes the events into the self-healing knowledge base. This includes: obtaining real-time conductor temperature data from the conductor thermal model and comparing it with the predicted temperature rise value to calculate the temperature deviation; when the temperature deviation exceeds a preset threshold, correcting the model parameters based on historical temperature data using the least squares method; constructing the synchronous phase-locked loop consistency index, calculating the real-time phase angle difference based on the phasor synchronization deviation, and comparing it with a preset threshold to determine phase synchronization; collecting protection action records from the protection device, statistically analyzing the frequency and timing characteristics, and performing correlation analysis with the temperature deviation and the synchronous phase-locked loop consistency index; adjusting the active and reactive power compensation of the flexible interconnection device through a proportional-integral-derivative controller according to the combined state of the temperature deviation, the synchronous phase-locked loop consistency index, and the protection action records, with the adjustment coefficient set according to the distribution network response characteristics; recording the monitoring results and compensation adjustment behavior as an event log and writing it into the self-healing knowledge base, the event log including timestamps, operating status indicators, and compensation adjustment data.

[0015] This preferred solution utilizes an edge controller to dynamically monitor and compare multi-dimensional data, including conductor thermal model prediction deviations, phase synchronization indicators, and protection action records. This allows for accurate identification of deviation trends and potential risks in the operation of overhead distribution line systems, thereby enabling adaptive adjustment of compensation parameters for flexible interconnection devices. The compensation strategy not only dynamically modifies based on the current state but also accumulates historical operational experience by recording it in a self-healing knowledge base via event logs for subsequent optimization. This solution enhances the adaptability of the control strategy while constructing a knowledge-driven self-healing control framework for future evolution, thereby strengthening stable operation under complex conditions.

[0016] This invention provides a self-healing system for faults in overhead power distribution lines.

[0017] To address the aforementioned technical problems, this invention provides the following technical solution: a self-healing system for overhead power line faults in a distribution network, comprising: a reference generation module, a sequence generation module, a coordination control module, a filtering control module, and a parameter optimization module; the reference generation module is used to deploy synchronous phasor measurement units on both sides of the flexible interconnection device and the key sectionalizing switch, continuously collecting voltage phasors and current phasors, generating a unified phasor reference through cloud-edge collaborative calculation, and broadcasting it to the local controller; the sequence generation module is used by the edge coordination engine to calculate the power flow changes after loop closure based on the unified phasor reference and instantaneous topology state, forming an action sequence, and simultaneously writing it into the trigger queues of the flexible interconnection device and the sectionalizing switch; The coordination control module is used by the local controller to obtain the coordination coefficient by performing membership reasoning on phasor synchronization deviation and harmonic-thermal risk, and to control the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold. The filtering control module is used for the line harmonic sensor to continuously upload spectrum data, and the self-tuning filter in the flexible interconnection device to suppress higher-order components in real time according to the harmonic distribution, and push the temperature rise prediction value to the conductor thermal model. The parameter optimization module is used by the edge controller to cyclically compare the conductor thermal model, the synchronization phase-locked loop consistency index and the protection action record, adaptively correct the compensation parameters of the flexible interconnection device, and write the event into the self-healing knowledge base.

[0018] 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 above-described method for self-healing faults in overhead power distribution lines.

[0019] 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 above-described method for self-healing faults in overhead power distribution lines.

[0020] The beneficial effects of this invention are as follows: By deploying synchronous phasor measurement units on both sides of the flexible interconnect device and the key segment switch, this invention continuously collects voltage and current phasor data and generates a unique time stamp through cloud-edge collaborative calculation. This ensures the coordinated synchronization of the flexible interconnect device and the segment switch during the re-looping after fault isolation, effectively avoiding the timing misalignment caused by inconsistent measurement and control cycles, and reducing the risk of voltage jumps and phase imbalances at the moment of loop closure.

[0021] By pre-adjusting the compensation parameters of the flexible interconnection device, the voltage and current surges at the moment of loop closure are reduced, and the risk of harmonic current returning along high-impedance lines is lowered. This not only provides a smooth transition environment for distribution network reconfiguration, but also demonstrates the foresight of the solution in the fault recovery process by dynamically optimizing the power flow distribution.

[0022] By quantitatively assessing phasor synchronization deviation and harmonic-thermal risks, and combining this with membership inference to generate coordination coefficients, the pre-compensation and sectionalizing switch closing timing of the flexible interconnection device are precisely controlled. During loop-closing operations, the device remains in a safe and stable state, effectively preventing secondary tripping and conductor overheating caused by phase mismatch or harmonic currents. Through the combination of quantification and inference, the local controller achieves precise decision-making during the fault self-healing process.

[0023] The self-tuned filter dynamically suppresses high-order harmonic components based on real-time uploaded spectrum data and predicts temperature rise using a conductor thermal model, achieving feedforward-based conductor thermal safety control. By adjusting compensation current and power flow in real time, it reduces the risk of conductor temperature rise, extends equipment lifespan, and improves power quality in the distribution network.

[0024] The edge controller adaptively corrects the compensation parameters of the flexible interconnection device by cyclically comparing the conductor thermal model, the synchronous phase-locked loop consistency index, and protection action records. It also writes key events into a self-healing knowledge base, providing parameter templates for the next fault reconfiguration. This achieves continuous optimization and intelligence in fault self-healing, enabling the distribution network to continuously improve its disturbance resistance and power supply reliability when facing multiple faults. Attached Figure Description

[0025] 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.

[0026] Figure 1 This is a flowchart illustrating a self-healing method for overhead power line faults in a distribution network, as provided in one embodiment of the present invention.

[0027] Figure 2This is a schematic diagram of a fault self-healing system for overhead power distribution lines provided in one embodiment of the present invention. Detailed Implementation

[0028] 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.

[0029] Example 1, referring to Figure 1 This is one embodiment of the present invention, which provides a self-healing method for faults in overhead distribution lines, comprising:

[0030] S1. Synchronous phasor measurement units are deployed on both sides of the flexible interconnection device and the key segment switch to continuously collect voltage phasors and current phasors. A unified phasor reference is generated by cloud-edge collaborative calculation and broadcast to the local controller.

[0031] S2, the edge coordination engine relies on a unified phasor reference and instantaneous topology state to calculate the power flow changes after loop closure and form an action sequence, which is then written into the trigger queues of the flexible interconnect device and the segmented switch.

[0032] S3. The local controller performs membership reasoning on phasor synchronization deviation and harmonic-thermal risk to obtain the coordination coefficient, and controls the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold.

[0033] S4. The line harmonic sensor continuously uploads spectrum data. The self-tuning filter in the flexible interconnect device suppresses higher-order components in real time according to the harmonic distribution and pushes the temperature rise prediction value to the conductor thermal model.

[0034] S5, the edge controller cyclically compares the lead thermal model, synchronous phase-locked loop consistency index and protection action records, adaptively corrects the compensation parameters of the flexible interconnection device, and writes the events into the self-healing knowledge base.

[0035] In summary, through steps S1-S5 of this invention, a full-process control link for fault self-healing of overhead distribution lines is constructed, realizing a closed-loop operation mechanism from fault perception, power flow prediction, coordinated control, to harmonic suppression and thermal safety management. Specifically, unified phasor reference and topology awareness ensure the accuracy of data-driven decision-making; fuzzy inference of coordination coefficients improves the robustness of loop-closing operations; harmonic mitigation and thermal model fusion enhance equipment protection capabilities; and adaptive compensation correction and knowledge base updates achieve intelligent evolution and experience reuse. This method possesses strong systematicity and adaptability, making it suitable for fault self-healing control deployment in complex distribution network scenarios.

[0036] Example 2, an embodiment of the present invention, provides a self-healing method for faults in overhead distribution lines based on the previous embodiment, including:

[0037] In this embodiment, the unified phasor reference in step S1 can be achieved by deploying synchronous phasor measurement units on both sides of the flexible interconnection device and the key sectionalizing switch to continuously collect local voltage and current phasors. These data are then uploaded to a cloud computing platform via edge computing nodes. The cloud platform uses a time synchronization algorithm to uniformly calibrate the data from multiple measurement units, outputting a globally consistent phasor reference result. This result is then broadcast to the local controller via network as a reference for subsequent control decisions. The unified phasor reference not only reflects the current electrical state of the overhead distribution line system but is also used in subsequent power flow prediction, action timing generation, and fuzzy control calculations. It is the core quantity for time and state coordination in the entire fault self-healing chain.

[0038] In one alternative implementation, the unified phasor reference can also be achieved by the regional master station selecting the measurement value of a certain node as a reference node within a time period and broadcasting the phasor data of that node to the entire network. Other nodes only need to perform difference calculations based on their local measurements and the reference node to form a relative reference, thus avoiding complex synchronous calculations in the cloud.

[0039] In another alternative implementation, the unified phasor reference can also abandon the strategy of a unified phasor reference across the entire network, and use only the local phasor data collected by each local controller as the control judgment input. Each independent controller makes local judgments and action decisions, without relying on a globally consistent phasor reference, which is suitable for asynchronous operation or distributed autonomous scenarios.

[0040] This invention introduces a cloud-edge collaborative structure to unify the time and phasor reference systems of each measurement point, achieving globally consistent state awareness. This provides a unified input for subsequent action coordination, fuzzy reasoning, and power flow prediction, effectively improving the accuracy and timeliness of fault handling and enhancing the adaptability of the distribution network overhead line system to different synchronization scenarios.

[0041] Furthermore, in step S1, synchronous phasor measurement units are deployed on both sides of the flexible interconnect device and the key segment switch to continuously collect voltage and current phasors. A unified phasor reference is generated by cloud-edge collaborative calculation and broadcast to the local controller, including the following steps A1-A4:

[0042] A1. Install synchronous phasor measurement units on both sides of the flexible interconnection device and the key segment switch to acquire voltage phasors and current phasors and transmit them to edge computing nodes and cloud computing platforms through a high-speed communication network.

[0043] A2. Edge computing nodes preprocess the received data and then upload it to the cloud computing platform.

[0044] A3. The cloud computing platform calibrates data from each synchronous phasor measurement unit based on a time synchronization algorithm to generate a unified phasor reference.

[0045] A4. Distribute the unified phasor reference to the local controller via broadcast.

[0046] Synchronous phasor measurement units are installed on both sides of the flexible interconnection device and the key sectionalizing switch to measure voltage and current phasor data in real time. The voltage and current phasor data collected by the synchronous phasor measurement units are transmitted to the cloud computing platform and edge computing nodes via a high-speed communication network. The edge computing nodes preprocess the voltage and current phasor data and then upload them to the cloud computing platform. The cloud computing platform calibrates the voltage and current phasor data using a synchronization algorithm to generate a unified phasor reference. The cloud computing platform broadcasts the unified phasor reference to the local controller as a time reference and data reference for the coordinated operation of the flexible interconnection device and the key sectionalizing switch.

[0047] In the process of self-healing faults in overhead distribution lines, step S1 involves deploying synchronous phasor measurement units, continuously collecting voltage and current phasor data, using cloud-edge collaborative computing to generate a unified phasor reference and broadcasting it to the local controller, thus providing accurate time references and data support for subsequent fault isolation and reconfiguration.

[0048] Specifically, in step A1, synchronous phasor measurement units are installed on both sides of the flexible interconnection device and key sectionalizing switch of the distribution network overhead line to measure the phasor information of voltage and current in real time, including amplitude and phase angle. The synchronous phasor measurement units rely on the time synchronization signal provided by the Global Positioning System to ensure that all measurement data have a unified time reference. The selection of the installation location is based on the key nodes of the distribution network to comprehensively monitor the electrical status of the line.

[0049] The purpose of deploying synchronous phasor measurement units is to grasp the operating status of overhead distribution lines by acquiring high-precision phasor data in real time. The high-precision measurement capability and time synchronization characteristics of the synchronous phasor measurement units can accurately reflect the voltage and current changes of key nodes, providing a reliable data source for subsequent fault location and reconstruction, and enhancing observability to ensure that necessary electrical information can be obtained quickly when a fault occurs.

[0050] Specifically, in step A2, the synchronous phasor measurement unit continuously collects voltage and current phasor data of the overhead distribution network lines and transmits this data to the cloud computing platform and edge computing nodes via a high-speed communication network. The voltage phasor data includes the voltage amplitude and phase angle of each node, and the current phasor data includes the current amplitude and phase angle in the line. The data acquisition frequency remains constant to capture the dynamic changes of the distribution network, and a high-speed communication network is used during transmission to ensure the timeliness and integrity of the data.

[0051] The purpose of continuously collecting voltage and current phasor data is to monitor the electrical status of the distribution network in real time, enabling a rapid response in the event of a fault. The application of high-speed communication networks ensures low latency and high reliability during data transmission, avoiding data loss due to network congestion or interruptions.

[0052] Specifically, in step A3, the cloud computing platform receives voltage phasor data and current phasor data from all synchronous phasor measurement units, and calibrates these data through a synchronization algorithm to generate a unified phasor reference.

[0053] Edge computing nodes first preprocess the locally collected data, including timestamp alignment and data filtering, to reduce the burden on the cloud computing platform. The cloud computing platform then performs the following steps:

[0054] For the voltage phasor data and current phasor data uploaded by each synchronous phasor measurement unit, interpolation adjustment is performed based on the timestamp difference to align all data to the same time point; the interpolation adjustment is achieved through linear interpolation, that is, the intermediate value is calculated based on the order of the timestamps.

[0055] Calculating a unified voltage phasor reference: The voltage phasor data from all synchronous phasor measurement units are weighted and averaged. The weights are determined based on the measurement accuracy and network transmission delay of each synchronous phasor measurement unit. Units with higher measurement accuracy and lower transmission delay receive higher weights.

[0056] Calculate a unified current phasor reference: Perform a weighted average on the current phasor data of all synchronous phasor measurement units, with the weighting method being consistent with that of the voltage phasor reference.

[0057] The unified phasor reference consists of a globally unified timestamp, a unified voltage phasor reference, and a unified current phasor reference, serving as a reference standard.

[0058] The purpose of cloud-edge collaborative computing in generating a unified phasor reference is to eliminate time and data discrepancies between synchronized phasor measurement units through global calibration, ensuring that all devices operate based on a consistent reference standard. Preprocessing at edge computing nodes reduces the load on the cloud computing platform and improves data processing efficiency; while global calibration by the cloud computing platform guarantees the accuracy and consistency of the phasor reference.

[0059] Specifically, in step A4, the cloud computing platform distributes the generated unified phasor reference to all local controllers via a broadcast mechanism, including the controllers of the flexible interconnect device and the sectionalizing switch. The frequency of the broadcast process is consistent with the sampling frequency of the synchronous phasor measurement unit to ensure the real-time performance of the data. After receiving the unified phasor reference, the local controller stores it and uses it as a time reference and data reference for subsequent actions to guide the coordinated operation of the flexible interconnect device and the sectionalizing switch.

[0060] The purpose of broadcasting a unified phasor reference is to ensure that all local controllers make decisions and operate based on the same voltage and current phasor data when performing fault self-healing actions. This reduces the risk of voltage spikes or harmonic currents caused by phase angle differences, improving stability during the reconfiguration process. The efficient distribution characteristics of the broadcast mechanism ensure that data can cover all devices in a short time, enhancing coordination capabilities.

[0061] In use, by continuously aggregating voltage and current phasor data, it provides raw input for cloud-edge collaborative computing; the collaborative work of the cloud computing platform and edge computing nodes generates a unified phasor reference, which is then distributed to the local controller through a broadcast mechanism, forming a complete processing chain; this ensures the continuity and consistency of data from acquisition to application, ultimately providing an accurate time reference and data support for the self-healing of faults in overhead power distribution lines.

[0062] In this embodiment of the application, the action sequence in step S2 can be a multi-stage control command sequence that includes pre-compensation, closing execution and subsequent tracking, determined by the edge coordination engine based on a unified phasor reference and instantaneous topology state prediction of loop power flow changes. This action sequence is generated by the edge coordination engine before loop closure, with operation timing and target control parameters as its core content, and is written into the trigger queues of the flexible interconnection device and the key segment switch to ensure that each control device completes its own action at the specified time and avoids power flow impact.

[0063] In one alternative implementation, the action sequence can also be a preset fixed control sequence that does not rely on power flow prediction analysis. Under normal operating conditions, it can directly call the operation sequence in the form of a general template, such as the three-step method of fixed delay compensation, closing, and voltage regulation, and ensure the execution process by preset time delay.

[0064] In another alternative implementation, the action sequence can also be a single-stage control command dynamically generated based on a real-time event triggering strategy. It can trigger the closing action only when the coordination coefficient meets the set conditions, and perform feedback adjustment after closing. It does not include pre-compensation and tracking stages, and is suitable for emergency closing or strategy lightweight scenarios.

[0065] This invention achieves a high degree of coordination in control operations during loop closing by employing a structured action sequence design driven by power flow prediction.

[0066] Furthermore, in step S2, the edge coordination engine, relying on the unified phasor reference and instantaneous topology state, calculates the power flow changes after loop closure and forms an action sequence, which is simultaneously written into the trigger queues of the flexible interconnect device and the segmented switch, including the following steps B1-B4:

[0067] B1. The edge coordination engine receives a unified phasor reference from the synchronous phasor measurement unit and the current instantaneous topology state.

[0068] B2. The edge coordination engine constructs a distribution network model based on a unified phasor reference and instantaneous topology state, and uses an iterative algorithm to perform power flow calculations to obtain the power flow change results after the loop closure operation.

[0069] B3. Based on the power flow change results, construct an action sequence that includes three stages: compensation, closing, and tracking, and determine the execution timing of each stage.

[0070] B4. Write the action sequence into the trigger queue of the flexible interconnect device and the segment switch, and set time stamps to ensure that each control action is executed in the predetermined order.

[0071] The edge coordination engine, based on a unified phasor reference and instantaneous topology state, uses the Newton-Raphson method to calculate the power flow changes after loop closure, generating a coordinated action sequence that includes compensation, closing, and tracking. This coordinated action sequence is then directly written into the trigger queues of the flexible interconnection device and the sectionalizing switch to drive them to perform corresponding real-time operations. In step S2 of the self-healing method for overhead line faults in the distribution network, the edge coordination engine uses the unified phasor reference and instantaneous topology state of the distribution network generated in step S1 to pre-calculate the power flow changes after loop closure and generate a coordinated action sequence for the flexible interconnection device and the sectionalizing switch.

[0072] In this embodiment of the application, the coordination coefficient in step B1 can be a control decision quantity generated by the local controller based on the real-time phasor synchronization deviation and harmonic-thermal risk as joint inputs, through a three-stage process of fuzzification, fuzzy inference and defuzzification in the fuzzy logic system. The fuzzy rule set is set according to historical operating experience, and finally the defuzzification calculation is performed by the centroid method to output the result, which is used to comprehensively evaluate the adaptability of the current distribution network overhead line system state to the loop closing operation.

[0073] In an alternative implementation, the coordination coefficient can also be calculated directly using a preset linear weighting function based solely on the phasor synchronization deviation as input, without introducing a fuzzy inference structure. This is suitable for operating scenarios in overhead distribution network systems where harmonic levels are low and thermal risks are negligible.

[0074] In another optional implementation, the coordination coefficient can also be calculated by a nonlinear scoring model jointly constructed from multiple operating indicators such as phasor synchronization deviation, harmonic-thermal risk and voltage fluctuation rate, and output through a trained neural network regression model as a data-driven auxiliary decision variable to participate in control judgment.

[0075] This invention generates a coordination coefficient as a criterion for the state of the overhead power line system by introducing a joint fuzzy reasoning mechanism of phasor synchronization and thermal risk. While retaining the physical meaning of the index, it introduces nonlinear expression capability, which helps to improve the judgment accuracy of loop closing operation and the flexibility of adjustment strategy.

[0076] Specifically, in step B1, the edge coordination engine receives the unified phasor reference generated in step one from the local controller, including a global unified timestamp, a unified voltage phasor reference, and a unified current phasor reference.

[0077] The unified voltage phasor reference represents the voltage amplitude and phase angle of key nodes in the distribution network, and the unified current phasor reference represents the current amplitude and phase angle of the corresponding branch. Both use a globally unified timestamp as the time reference. At the same time, the edge coordination engine obtains the instantaneous topology status from the distribution network monitoring module, including the open-loop or closed-loop status of the current line, the segmentation status after fault isolation, and the operating mode of the flexible interconnection device, such as active power regulation mode or reactive power compensation mode.

[0078] The purpose of obtaining a unified phasor reference and instantaneous topology is to provide accurate electrical parameters and network structure information for subsequent power flow calculations. A unified phasor reference ensures the consistency of data in both time and value, avoiding inaccuracies in calculations caused by time asynchrony or measurement deviations.

[0079] Specifically, in step B2, the edge coordination engine calculates the power flow distribution after the loop closure operation based on the mathematical model of the distribution network, combined with a unified phasor reference and instantaneous topology state. The calculation process uses the Newton-Raphson method, and the specific steps are as follows:

[0080] First, the node admittance matrix of the distribution network is constructed based on the instantaneous topology state. The matrix elements are determined by the line impedance and the connection relationship between nodes, and the matrix structure is updated after loop closure. Then, a unified voltage phasor reference is used as the initial voltage estimate, and the branch current is initialized in combination with a unified current phasor reference. The branch current is substituted into the power flow equation, which is expressed as the relationship between the node injection current and the product of the node admittance matrix and the node voltage. Next, the nonlinear equations in the power flow equation are solved iteratively until the results converge, and the node voltage amplitude and phase angle, as well as the branch current amplitude and phase angle after loop closure, are obtained. The convergence condition is that the changes in voltage and current are less than a preset accuracy threshold.

[0081] The purpose of estimating power flow changes after loop closure is to predict the impact of loop closure operations on the electrical state of the distribution network, providing data support for the pre-regulation of flexible interconnection devices. The Newton-Raphson method can efficiently solve nonlinear power flow problems in distribution networks, ensuring the accuracy of the calculation results and the convergence speed. By understanding the voltage and current distribution after loop closure in advance, targeted measures can be taken before operation to reduce the electrical impact at the moment of loop closure and improve the stability of distribution network reconfiguration.

[0082] Specifically, in step B3, the edge coordination engine generates a sequence of coordinated actions between the flexible interconnect device and the segmented switch based on the power flow calculation results, which is divided into three stages:

[0083] The first stage is the compensation phase. Based on the calculated power flow changes after the loop is closed, the flexible interconnection device adjusts the reactive power compensation and active power regulation in advance, with the goal of reducing the voltage difference and current surge at the moment of loop closure.

[0084] The second stage is the post-closing stage. After the flexible interconnection device completes the pre-compensation, the sectionalizing switch performs the closing operation to complete the distribution network reconstruction. The closing time is set to a fixed delay after the pre-compensation is completed to ensure that the compensation measures take effect.

[0085] Finally, in the re-tracking phase, after loop closure, the flexible interconnect device continuously monitors the actual node voltage and branch current, and fine-tunes the reactive power compensation and active power regulation based on the deviation of the calculated results to maintain power flow stability. The timing of the action sequence is precisely determined by the edge coordination engine based on the power flow calculation results and device response time.

[0086] The purpose of forming a sequence of actions—compensation, closing, and tracking—is to reduce the electrical impact of loop-closing operations on the distribution network through the coordinated control of flexible interconnection devices and sectionalizing switches. The compensation phase mitigates power flow fluctuations after loop closure through pre-adjustment; the closing phase, performed after compensation takes effect, ensures a smooth transition of voltage and current; and the tracking phase responds to dynamic changes during operation through real-time adjustments.

[0087] Specifically, in step B4, the edge coordination engine writes the coordinated action sequence into the trigger queues of the flexible interconnection device and the sectionalizing switch, and uses time stamping to ensure the execution timing. The trigger queue of the flexible interconnection device contains the pre-compensation start time and compensation parameters, and the trigger queue of the sectionalizing switch contains the closing time. The closing time is set to be later than the pre-compensation start time plus the time required for compensation to take effect. The writing process ensures that the action sequence is executed in the specified order by verifying the consistency of the globally unified timestamp.

[0088] The purpose of writing to the trigger queue is to convert the coordinated action sequence into executable instructions and ensure that the flexible interconnection device and sectionalizing switch operate in a predetermined time sequence. The application of time stamping ensures the accuracy of the action timing and avoids voltage or current abnormalities caused by incorrect execution order; precise timing control enhances the coordinated execution capability and ensures a smooth switching of the distribution network status during fault self-healing.

[0089] In use, data support is generated by calculating the power flow changes after loop closure. Based on the calculation results, a coordinated action sequence of compensation, closing, and tracking is formed. Finally, precise control of the flexible interconnection device and sectionalizing switch is achieved by writing the sequence into the trigger queue, ensuring the continuity and consistency from data acquisition to action execution. Through predictive analysis, coordinated adjustment, and timing management, the stability and security of reconfiguration during the self-healing process of overhead distribution lines are effectively improved.

[0090] Furthermore, in step S3, the local controller performs membership reasoning on phasor synchronization deviation and harmonic-thermal risk to obtain a coordination coefficient, and controls the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold, including the following steps C1-C4:

[0091] C1. The local controller acquires real-time voltage phasors and compares them with a unified phasor reference to calculate the phase angle difference and quantify the phasor synchronization deviation.

[0092] C2. Collect current harmonic current data and calculate its impact on conductor temperature rise to quantify harmonic-thermal risk.

[0093] C3. Using phasor synchronization deviation and harmonic-thermal risk as inputs, a coordination coefficient is generated through fuzzy inference.

[0094] C4. Compare the coordination coefficient with the preset threshold to control the compensation operation of the flexible interconnection device and the closing timing of the sectionalizing switch.

[0095] The local controller quantifies phasor synchronization deviation by calculating the difference between the phase angle of the real-time voltage phasor and the phase angle of the unified phasor reference; it quantifies harmonic-thermal risk by calculating the conductor temperature rise effect caused by harmonic current; using phasor synchronization deviation and quantified harmonic-thermal risk as inputs, it generates coordination coefficients through membership inference using a fuzzy logic system. Based on the comparison results of the coordination coefficients with preset thresholds, it controls the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switches. The local controller quantifies and evaluates phasor synchronization deviation and harmonic-thermal risk, and generates coordination coefficients through membership inference to control the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switches. The coordination coefficients are generated through a three-stage process in fuzzy logic—fuzzification, fuzzy inference, and defuzzification—using phasor synchronization deviation and harmonic-thermal risk as joint inputs. The fuzzy rule set is preset based on historical operating experience, and the defuzzification process uses the centroid method for output calculation.

[0096] Specifically, in step C1, the local controller acquires real-time voltage and current phasors from the synchronization phasor measurement unit and compares them with a unified phasor reference. The phasor synchronization deviation is determined by calculating the difference between the phase angle of the real-time voltage phasor and the phase angle of the unified phasor reference. Specifically, the phase angle difference is obtained by subtracting the phase angle of the unified phasor reference from the phase angle of the real-time voltage phasor. The smaller the phase angle difference, the higher the synchronization between the flexible interconnect device and the sectionalizing switch, and the lower the risk of voltage surges during loop closing. The purpose of quantifying the phasor synchronization deviation is to evaluate the timing consistency of the flexible interconnect device and the sectionalizing switch. As a direct indicator, the phase angle difference can accurately reflect the degree of voltage phase matching at the moment of loop closing, effectively preventing voltage surges and inrush currents caused by phase mismatch.

[0097] Specifically, in step C2, the local controller acquires real-time harmonic current data from the line harmonic sensor and decomposes its spectrum using a fast Fourier transform to extract higher-order harmonic components. Harmonic-thermal risk is quantified by calculating the conductor temperature rise effect caused by harmonic current.

[0098] The specific calculation process is as follows: First, multiply the square of the amplitude of each harmonic current by the AC resistance of the conductor at the corresponding frequency to obtain the temperature rise contribution of each harmonic component; then, add up the temperature rise contributions of all harmonic components, and multiply the result by the thermal conductivity coefficient of the conductor to obtain the total harmonic-thermal risk value. The thermal conductivity coefficient of the conductor is determined by the conductor material and structural characteristics.

[0099] The purpose of quantifying harmonic-thermal risk is to assess the impact of harmonic currents on conductor temperature and insulation life. The temperature rise effect caused by harmonic currents is a major cause of conductor overheating and insulation aging. By accurately calculating the temperature rise effect, the thermal safety margin of the conductor can be predicted, providing a basis for subsequent control measures. This method fully considers the nonlinear relationship between harmonic frequency and conductor resistance, ensuring the accuracy and reliability of the risk assessment.

[0100] In this embodiment, the coordination coefficient in step C3 can be jointly input from phasor synchronization deviation and harmonic-thermal risk into fuzzy logic, where they are fuzzified separately. Fuzzy inference is then performed using a predefined set of fuzzy rules, and finally, defuzzification is achieved using the centroid method to obtain a continuous value between 0 and 1, indicating whether the current distribution network overhead line system is suitable for loop closure. The closer the coordination coefficient is to 1, the more stable the distribution network overhead line system is, and the more suitable it is for loop closure.

[0101] In an alternative implementation, the coordination coefficient can also be obtained by using a weighted linear combination method, which involves normalizing the phasor synchronization deviation and the harmonic-thermal risk and then weighting them together to obtain the coordination coefficient, ignoring the fuzzy inference process and reducing computational complexity.

[0102] In another alternative implementation, the coordination coefficient can also be calculated using only the phasor synchronization deviation as input, and a single index can be obtained through empirical formulas. This index is used as a threshold reference for judging the loop closure condition, without considering the synergistic effect of harmonic-thermal risks.

[0103] This invention introduces a coordination coefficient as the core criterion for loop closure conditions, comprehensively reflecting the operating status of the overhead distribution line system in two dimensions: instantaneous phasor synchronization and thermal safety risk. This improves the scientific nature and robustness of loop closure decisions, while also taking into account control accuracy and response speed.

[0104] Specifically, in step C3, the local controller takes the phasor synchronization deviation and the quantized harmonic-thermal risk as inputs, and performs membership reasoning through a fuzzy logic system to generate coordination coefficients.

[0105] The specific process is as follows: First, the phasor synchronization deviation and the quantized harmonic-thermal risk are fuzzified into multiple levels such as low, medium, and high. Then, based on the predefined fuzzy rule set, the fuzzy output is calculated using the fuzzy inference method. Finally, the fuzzy output is defuzzified using the centroid method to obtain the precise value of the coordination coefficient. The value range of the coordination coefficient is set to 0 to 1. The larger the value, the more suitable the distribution network overhead line system state is for performing loop closing operation.

[0106] The purpose of obtaining the coordination coefficient through membership reasoning is to comprehensively evaluate the impact of phasor synchronization deviation and harmonic-thermal risk on the stability of the distribution network overhead line system. The fuzzy logic system can effectively handle the uncertainties and nonlinear relationships in the distribution network operation environment. The coordination coefficient can intuitively reflect whether the current state of the distribution network overhead line system is suitable for loop closing operation, thereby improving the intelligence and adaptability of decision-making and ensuring that the distribution network overhead line system can still maintain stable operation under complex conditions.

[0107] Specifically, in step C4, the local controller compares the coordination coefficient with a preset threshold and controls the operation of the flexible interconnection device and the sectionalizing switch based on the comparison result. Specifically, if the coordination coefficient is greater than or equal to the preset threshold, the flexible interconnection device is triggered to perform pre-compensation, while the sectionalizing switch is allowed to close according to a predetermined action sequence. If the coordination coefficient is less than the preset threshold, the compensation amount of the flexible interconnection device is cyclically adjusted by the proportional-integral controller until the coordination coefficient reaches or exceeds the preset threshold. The adjustment of the compensation amount is based on the difference between the coordination coefficient and the preset threshold. Through the combined action of the proportional and integral terms, the overhead power distribution line system gradually approaches safe operating conditions.

[0108] The purpose of comparing the coordination coefficient with a preset threshold to control the action is to ensure that the loop-closing operation is performed under safe conditions in the distribution network overhead line system. The preset threshold, as a safety boundary, effectively avoids operation under high-risk conditions, preventing voltage surges and conductor overheating. The application of a proportional-integral controller enables dynamic adjustment of the compensation amount, improving the response speed and stability of the distribution network overhead line system.

[0109] In use, coordination coefficients are generated through membership reasoning, and the actions of flexible interconnection devices and sectional switches are controlled based on the comparison results of coordination coefficients and preset thresholds. A complete logical chain is formed from risk assessment to control decision-making, ensuring the continuity and consistency of the processing. Through precise risk quantification, intelligent decision-making mechanisms and dynamic control adjustments, the safety and reliability of reconstruction during the self-healing process of overhead power distribution lines can be improved.

[0110] Furthermore, in step S4, the line harmonic sensor continuously uploads spectral data, and the self-tuning filter in the flexible interconnect device suppresses higher-order components in real time according to the harmonic distribution, and pushes the temperature rise prediction value to the conductor thermal model, including the following steps D1-D4:

[0111] D1. Harmonic sensors installed at key nodes of overhead power distribution lines continuously collect the spectrum data of branch currents and upload it to the flexible interconnection device to reflect the distribution of harmonic currents in real time.

[0112] D2. The self-tuning filter configured in the flexible interconnect device dynamically adjusts the filtering parameters based on the spectrum data to generate a compensation current to cancel out high-order harmonic components that exceed the threshold.

[0113] D3. The flexible interconnect device combines spectrum data with the fundamental component of branch current to predict the temperature rise trend of the conductor based on the conductor thermal model, and forms a thermal state estimate for the future time period.

[0114] D4. When the predicted temperature rise exceeds the safety threshold, the flexible interconnect device triggers the feedforward control mechanism to adjust the active power regulation and reactive power compensation, control the branch power flow, reduce the heat generation power, and maintain the conductor temperature within the set range.

[0115] The line harmonic sensor monitors the harmonic components in the branch current in real time and uploads the spectrum data set to the flexible interconnection device. The self-tuning filter in the flexible interconnection device dynamically adjusts the filtering parameters according to the spectrum data set to generate a compensation current to cancel high-order harmonic components exceeding a preset threshold. The flexible interconnection device predicts the conductor temperature based on the spectrum data set and the fundamental component of the branch current, combined with the conductor thermal model. When the predicted conductor temperature exceeds the safety threshold, the flexible interconnection device controls the branch power flow by adjusting the active power regulation and reactive power compensation to reduce the heat generation power and ensure that the conductor temperature is maintained within a safe range. In step four of the self-healing method for faults in overhead distribution lines, after the circuit breaker is closed, precise control of conductor temperature and thermal safety management are achieved by real-time monitoring of harmonic current and combining it with the conductor thermal model.

[0116] Specifically, in step D1, line harmonic sensors are installed at key nodes of the overhead distribution line to continuously monitor the harmonic components in the branch current. The line harmonic sensors analyze the waveform of the branch current using fast Fourier transform technology, decompose the waveform into harmonic current amplitudes of different frequencies, and generate a set of spectrum data.

[0117] The spectrum data set is uploaded to the flexible interconnect device at high frequency to ensure real-time monitoring of the dynamic changes of harmonic current. The fast Fourier transform technology is a method to convert the time series data of branch current into frequency domain data. By calculating the amplitude of different frequency components, a spectrum data set is formed and provided for subsequent processing.

[0118] The purpose of continuously uploading spectrum data by line harmonic sensors is to monitor changes in harmonic currents in the distribution network in real time, so as to respond promptly to problems such as conductor overheating and insulation aging caused by harmonics. The application of Fast Fourier Transform technology can accurately decompose the harmonic components in the branch current waveform, providing accurate spectrum data. High-frequency uploading ensures the real-time nature of spectrum data, enabling rapid response to fluctuations in harmonic currents and improving the safety and stability of the distribution network.

[0119] Specifically, in step D2, the self-tuning filter configured in the flexible interconnection device adopts active filtering technology and dynamically adjusts the filtering parameters according to the spectrum data uploaded by the line harmonic sensor.

[0120] First, the system receives spectral data uploaded by line harmonic sensors. Then, it compares the amplitude of each harmonic current in the spectral data with a preset threshold, which is determined based on the conductor's thermal tolerance and insulation withstand capability. For harmonic components exceeding the threshold, a self-tuning filter generates a compensation current with the same amplitude but opposite phase to that harmonic component. Finally, the compensation current is injected into the distribution network through the power electronic converter of the flexible interconnection device to cancel out higher-order harmonic components. The generation of the compensation current is based on precise calculation of amplitude and phase to ensure complete cancellation with the target harmonic component.

[0121] The purpose of self-tuning filters in real time to suppress high-order harmonic components is to reduce the impact of harmonic current on conductor temperature and insulation life; active filtering technology can flexibly cope with harmonic components of different frequencies and amplitudes, and achieve precise suppression of harmonics by dynamically adjusting filter parameters; the injection of compensation current effectively reduces the harmonic current of conductors in the distribution network, reduces the heating caused by harmonics, extends the service life of conductors, and improves the power quality and reliability of the distribution network.

[0122] Specifically, in step D3, the flexible interconnection device predicts the temperature rise of the conductor based on the real-time spectrum data provided by the line harmonic sensor and the fundamental component of the branch current.

[0123] The conductor thermal model is based on the principle of thermal equilibrium, comprehensively considering the heating and cooling processes of the conductor. The heating power is generated by both the fundamental current and each harmonic current. In the calculation, the square of the fundamental current is multiplied by the DC resistance of the conductor to obtain the heating power of the fundamental component. Then, the square of the amplitude of each harmonic current is multiplied by the AC resistance at the corresponding frequency, and the sum is obtained to obtain the heating power of the harmonic component. The total heating power is the sum of the two. The cooling power is proportional to the difference between the conductor temperature and the ambient temperature, and is calculated by multiplying the convective heat dissipation coefficient by the heat dissipation surface area of ​​the conductor. The flexible interconnect device uses numerical methods to solve the thermal equilibrium equation and predict the trend of conductor temperature changes over a future period.

[0124] The purpose of temperature rise prediction and conductor thermal model is to monitor the temperature status of conductors in real time and prevent insulation aging and equipment damage caused by overheating. The application of the thermal balance principle can accurately simulate the thermal dynamic process of conductors, comprehensively consider the influence of fundamental current and harmonic currents, ensure the accuracy of prediction results, realize dynamic tracking of conductor temperature changes, support subsequent thermal safety control, and enhance preventive maintenance capabilities.

[0125] Specifically, in step D4, the flexible interconnection device compares the conductor temperature predicted by the conductor thermal model with a safety threshold. If the predicted conductor temperature exceeds the safety threshold, a feedforward control mechanism is triggered. The control method involves adjusting the active power regulation and reactive power compensation of the flexible interconnection device to alter the power flow in the branch, reduce the fundamental current, and decrease heat generation. The adjustment range of the active power regulation and reactive power compensation is proportional to the degree to which the predicted conductor temperature exceeds the safety threshold, and the adjustment coefficient is determined by the response characteristics of the distribution network. The adjusted active power regulation and reactive power compensation are output through a power electronic converter to ensure that the conductor temperature remains within a safe range.

[0126] The purpose of feedforward conductor thermal safety control is to proactively adjust distribution network operating parameters before conductor temperatures rise abnormally, preventing overheating. By adjusting active power regulation and reactive power compensation, it effectively controls the fundamental current amplitude in branches, reducing heat generation and ensuring conductor thermal safety. The feedforward control mechanism, through early intervention, avoids the lag of passive responses, improving safety and stability.

[0127] In use, a self-tuning filter suppresses high-order harmonic components in real time, and a conductor thermal model is used to predict the temperature rise. Finally, the operating parameters of the flexible interconnection device are adjusted through feedforward conductor thermal safety control, forming a complete closed-loop control chain. Through real-time monitoring, dynamic suppression, and feedforward control, the harmonic suppression capability and conductor thermal safety management level after the self-healing of faults in the distribution network overhead line can be effectively improved, making it suitable for practical engineering applications.

[0128] Furthermore, in step S5, the edge controller cyclically compares the wire thermal model, the synchronous phase-locked loop consistency index, and the protection action records, adaptively corrects the compensation parameters of the flexible interconnection device, and writes the events into the self-healing knowledge base, including the following steps E1-E4:

[0129] E1. Obtain real-time conductor temperature data from the conductor thermal model and compare it with the predicted temperature rise value to calculate the temperature deviation. When the temperature deviation exceeds the preset threshold, correct the model parameters based on historical temperature data using the least squares method.

[0130] E2. Construct a synchronous phase-locked loop consistency index, calculate the real-time phase angle difference based on phasor synchronization deviation, and compare it with a preset threshold to determine phase synchronization.

[0131] E3. Collect protection action records of the protection device, statistically analyze the frequency and timing characteristics, and perform correlation analysis with temperature deviation and synchronous phase-locked loop consistency index.

[0132] E4. Based on the combined status of temperature deviation, synchronous phase-locked loop consistency index and protection action record, the active power compensation and reactive power compensation of the flexible interconnection device are adjusted by a proportional-integral-derivative controller, and the adjustment coefficient is set according to the distribution network response characteristics.

[0133] E5. Record the monitoring results and compensation adjustment actions as event logs and write them into the self-healing knowledge base. The event logs include timestamps, operational status indicators, and compensation adjustment data.

[0134] The edge controller adaptively adjusts the active and reactive power compensation of the flexible interconnection device by monitoring in real time the deviation between the conductor temperature and the predicted value in the conductor thermal model, the phase synchronization in the synchronous phase-locked loop consistency index, and the operation status of the protection device in the protection action record, in order to cope with the dynamic changes in the operation of the distribution network. At the same time, the edge controller records the abnormal trends and adjustment results it detects into the self-healing knowledge base, providing optimized parameter templates for subsequent fault self-healing.

[0135] Specifically, in step E1, the edge controller obtains real-time conductor temperature data from the conductor thermal model and compares it with the predicted temperature rise value calculated based on the conductor thermal model, and calculates the temperature deviation between the two.

[0136] Temperature deviation is determined by the absolute difference between the real-time conductor temperature and the predicted temperature rise, and is used to evaluate the predictive accuracy of the conductor thermal model. A temperature deviation threshold is pre-set; if the calculated temperature deviation exceeds this threshold, it indicates a significant error between the conductor thermal model's prediction and the actual operating conditions, requiring correction of the model parameters. The correction process is achieved by adjusting the conductor's heat capacity and convective heat dissipation coefficient. Specifically, based on historical temperature data, the least squares method is used to fit the predicted temperature rise value, gradually bringing it closer to the real-time conductor temperature, thereby reducing the temperature deviation.

[0137] By iteratively comparing the conductor thermal model, the accuracy of conductor temperature predictions is monitored in real time, ensuring that the model reflects the actual thermal state of the distribution network. Calculating temperature deviations and comparing them with preset thresholds allows for timely detection of prediction errors, triggering parameter correction mechanisms and improving the accuracy and reliability of the conductor thermal model. Using the least squares method to fit historical temperature data for parameter adjustment enables dynamic optimization of the conductor thermal model, adapting it to changes in distribution network operating conditions. Furthermore, continuous calibration of the conductor thermal model ensures the effective implementation of thermal safety management during distribution network operation.

[0138] Specifically, in step E2, the edge controller defines a phase-locked loop (PLL) consistency index by calculating the ratio between the real-time phase angle difference and pi. This index measures the phase synchronization between the flexible interconnect device and the sectionalizing switch. The real-time phase angle difference is provided by the phasor synchronization deviation, representing the phase deviation when the flexible interconnect device and the sectionalizing switch close. The PLL consistency index is set to a range of 0 to 1, with values ​​closer to 1 indicating higher phase synchronization. The edge controller continuously monitors the trend of the PLL consistency index and compares it with a preset threshold. If the monitoring results show that the PLL consistency index is lower than this threshold, it indicates insufficient phase synchronization, requiring adjustment of the control parameters of the flexible interconnect device.

[0139] The monitoring of the phase-locked loop consistency index aims to evaluate the coordination between the flexible interconnect device and the segmented switch operation, ensuring voltage phase matching during loop closing. By using the ratio of real-time phase angle difference to pi as a quantitative indicator, the phase synchronization status can be intuitively reflected, facilitating real-time monitoring and control. The mechanism of comparing it with a preset threshold can promptly detect insufficient phase synchronization, triggering adjustment measures to reduce the phase angle difference, thereby improving operational smoothness.

[0140] Specifically, in step E3, the edge controller collects protection action records from the protection device, including information such as trip time, fault type, and reset status.

[0141] By statistically analyzing the frequency and time distribution of protection actions, abnormal patterns can be identified, such as multiple trips within a short period. Correlation analysis is performed between protection action records and conductor temperature deviations and synchronous phase-locked loop consistency indices to determine whether the anomaly is caused by harmonic currents or phase imbalance. The specific method of correlation analysis involves comparing the time points of protection actions with the changing trends of conductor temperature deviations and synchronous phase-locked loop consistency indices to determine the cause of the anomaly.

[0142] The purpose of analyzing protection action records is to monitor the operating status of distribution network protection devices and identify potential fault risks and malfunctions. By statistically analyzing the frequency and time distribution of protection actions, abnormal behavior of protection devices can be detected, allowing for timely countermeasures. Correlation analysis with conductor temperature deviation and synchronous phase-locked loop consistency index can accurately pinpoint the cause of anomalies, providing a basis for subsequent parameter adjustments. This method, through comprehensive analysis of protection action records, improves the diagnostic capability and reliability of distribution network fault self-healing.

[0143] Specifically, in step E4, the edge controller dynamically adjusts the active and reactive power compensation of the flexible interconnection device based on the monitoring results of conductor temperature deviation, synchronous phase-locked loop consistency index, and protection action records.

[0144] The specific adjustment strategy is as follows: when the conductor temperature deviation exceeds a preset threshold, reactive power compensation is increased to optimize voltage distribution and reduce branch current, while active power compensation remains unchanged; when the synchronization phase-locked loop consistency index is lower than a preset threshold, active power compensation is adjusted to reduce phase angle difference and enhance action coordination; when the protection action record shows frequent tripping, the adjustment range of active power compensation and reactive power compensation is reduced to reduce the interference of power flow changes on the protection device. The adjustment process is implemented using a proportional-integral-derivative controller, where the comprehensive error is calculated by summing the deviations of conductor temperature deviation and synchronization phase-locked loop consistency index according to a preset ratio. The proportional, integral, and derivative coefficients of the controller are predetermined based on the distribution network response characteristics.

[0145] The adaptive correction compensation parameters of the flexible interconnection device aim to dynamically optimize the control strategy based on real-time changes in the distribution network's operating status, thereby improving adaptability and stability. The adjustment strategy comprehensively considers conductor thermal state, phase synchronization, and protection action records to ensure stable operation of the distribution network overhead line system under multiple abnormal conditions. A proportional-integral-derivative controller is used to achieve precise adjustment, enabling rapid response to changes in the distribution network overhead line system's state and reducing the risks of conductor overheating, phase imbalance, and protection maloperation.

[0146] Specifically, in step E5, the edge controller records the detected abnormal trends and adjustment results as event logs and writes them to the self-healing knowledge base. The event logs include timestamps, real-time conductor temperatures, synchronization phase-locked loop consistency index, protection action records, and compensation parameter adjustment values. The self-healing knowledge base uses a time-series database for storage, supporting rapid retrieval and historical pattern analysis. Through statistical analysis and rule extraction of historical events, compensation parameter optimization templates are generated, providing a reference for subsequent fault reconstruction. The construction and application of the self-healing knowledge base enables the accumulation and reuse of distribution network fault self-healing experience.

[0147] The purpose of writing events into the self-healing knowledge base is to record abnormal events and adjustment measures during distribution network operation, providing experience support for subsequent fault self-healing. A time-series database is used to store event logs, ensuring rapid data storage and retrieval, facilitating historical pattern analysis and rule extraction. Generating compensation parameter optimization templates provides preset parameters for the next fault reconstruction, shortening response time and improving self-healing efficiency.

[0148] In operation, real-time information on the distribution network's operating status is obtained by monitoring the synchronization phase-locked loop consistency index and analyzing protection action records. Based on these monitoring results, the compensation parameters of the flexible interconnection device are adaptively adjusted to ensure stable operation of the distribution network overhead line system amidst dynamic changes. Finally, key events are written into the self-healing knowledge base to provide experience support for subsequent fault self-healing. From status monitoring to parameter adjustment and knowledge accumulation, a complete closed-loop control chain is formed. Through real-time monitoring, dynamic adjustment, and knowledge reuse, the adaptability, reliability, and intelligence level of fault self-healing for distribution network overhead lines are effectively improved.

[0149] Example 3, referring to Figure 2 This is one embodiment of the present invention, which provides a self-healing system for faults in overhead distribution lines, including a reference generation module, a sequence generation module, a coordination control module, a filtering control module, and a parameter optimization module.

[0150] The reference generation module is used to deploy synchronous phasor measurement units on both sides of the flexible interconnect device and the key segment switch to continuously collect voltage phasors and current phasors. A unified phasor reference is generated by cloud-edge collaborative calculation and broadcast to the local controller.

[0151] The sequence generation module is used by the edge coordination engine to calculate the power flow changes after loop closure based on a unified phasor reference and instantaneous topology state, and then form an action sequence, which is simultaneously written into the trigger queues of the flexible interconnect device and the segmented switch.

[0152] The coordination control module is used by the local controller to obtain the coordination coefficient by performing membership reasoning on phasor synchronization deviation and harmonic-thermal risk, and to control the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold.

[0153] The filter control module is used for the line harmonic sensor to continuously upload spectrum data. The self-tuning filter in the flexible interconnect device suppresses higher-order components in real time according to the harmonic distribution and pushes the temperature rise prediction value to the conductor thermal model.

[0154] The parameter tuning module is used by the edge controller to cyclically compare the lead thermal model, synchronous phase-locked loop consistency index and protection action records, adaptively correct the compensation parameters of the flexible interconnection device, and write the events into the self-healing knowledge base.

[0155] This embodiment also provides an electronic device applicable to a self-healing method for overhead power distribution line faults, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the self-healing method for overhead power distribution line faults as proposed in the above embodiment.

[0156] This embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements a self-healing method for faults in overhead power distribution lines as proposed in the above embodiments.

[0157] The storage medium proposed in this embodiment and the method for implementing a self-healing method for overhead power line faults in the above embodiments belong to the same inventive concept. Technical details not described in detail in this embodiment can be found in the above embodiments, and this embodiment has the same beneficial effects as the above embodiments.

[0158] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0159] 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 self-healing faults in overhead distribution lines, characterized in that: include, Synchronous phasor measurement units are deployed on both sides of the flexible interconnection device and the key segment switch to continuously collect voltage phasors and current phasors. A unified phasor reference is generated by cloud-edge collaborative calculation and broadcast to the local controller. The edge coordination engine relies on a unified phasor reference and instantaneous topology state to calculate the power flow changes after loop closure and form an action sequence, which is simultaneously written into the trigger queues of flexible interconnect devices and segmented switches. The local controller obtains the coordination coefficient by performing membership reasoning on phasor synchronization deviation and harmonic-thermal risk, and controls the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold. The line harmonic sensor continuously uploads spectrum data, and the self-tuning filter in the flexible interconnect device suppresses high-order components in real time according to the harmonic distribution, and pushes the temperature rise prediction value to the conductor thermal model. The edge controller cyclically compares the lead thermal model, the synchronous phase-locked loop consistency index, and the protection action records, adaptively corrects the compensation parameters of the flexible interconnect device, and writes the events into the self-healing knowledge base.

2. The self-healing method for faults in overhead distribution lines as described in claim 1, characterized in that: The system involves deploying synchronous phasor measurement units on both sides of the flexible interconnect device and the key segment switch to continuously collect voltage and current phasors. A unified phasor reference is generated through cloud-edge collaborative calculation and broadcast to the local controller. Synchronous phasor measurement units are installed on both sides of the flexible interconnection device and the key segment switch to acquire voltage phasors and current phasors and transmit them to edge computing nodes and cloud computing platforms through a high-speed communication network. Edge computing nodes preprocess the received data before uploading it to the cloud computing platform; The cloud computing platform calibrates data from various synchronous phasor measurement units based on a time synchronization algorithm to generate a unified phasor reference. The unified phasor reference is distributed to the local controller via broadcast.

3. The self-healing method for faults in overhead distribution lines as described in claim 2, characterized in that: The edge coordination engine, relying on a unified phasor reference and instantaneous topology state, calculates the power flow changes after loop closure and forms an action sequence, which is simultaneously written into the trigger queues of the flexible interconnect device and the segmented switch, including... The edge coordination engine receives a unified phasor reference from the synchronized phasor measurement unit and the current instantaneous topology state; Based on a unified phasor reference and instantaneous topology, the edge coordination engine uses a power flow calculation algorithm to predict power flow changes under loop closing operations and identify power change trends in key branches. Based on the power flow change results, an action sequence consisting of three stages—compensation, closing, and tracking—is constructed, and the execution timing of each stage is determined. The action sequence is written into the trigger queue of the flexible interconnect device and the segment switch, and time stamps are set to ensure that each control action is executed in a predetermined order.

4. The self-healing method for overhead power distribution line faults as described in claim 3, characterized in that: The local controller obtains a coordination coefficient by performing membership inference on phasor synchronization deviation and harmonic-thermal risk, and controls the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold. include, The local controller acquires real-time voltage phasors and compares them with a unified phasor reference, and calculates the phase angle difference to quantify the phasor synchronization deviation. Collect current harmonic current data and calculate its impact on conductor temperature rise to quantify harmonic-thermal risk; Using phasor synchronization deviation and harmonic-thermal risk as inputs, a coordination coefficient is generated through fuzzy inference. The coordination coefficient is compared with a preset threshold to control the compensation operation of the flexible interconnection device and the closing timing of the sectionalizing switch.

5. The self-healing method for overhead power line faults in a distribution network as described in claim 4, characterized in that: The method of controlling the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold includes, The coordination coefficient is generated by taking phasor synchronization deviation and harmonic-thermal risk as joint inputs, and then going through a three-stage process of fuzzification, fuzzy inference and defuzzification in fuzzy logic. The fuzzy rule set is pre-set based on historical operating experience, and the defuzzification process uses the centroid method for output calculation.

6. The self-healing method for overhead power line faults in a distribution network as described in claim 5, characterized in that: The line harmonic sensor continuously uploads spectrum data, and the self-tuning filter in the flexible interconnect device suppresses higher-order components in real time according to the harmonic distribution, and pushes the temperature rise prediction value to the conductor thermal model, including... By installing harmonic sensors at key nodes of overhead power distribution lines, the spectrum data of branch current is continuously collected and uploaded to the flexible interconnection device to reflect the distribution of harmonic current in real time. The self-tuning filter configured in the flexible interconnect device dynamically adjusts the filtering parameters based on the spectrum data to generate a compensation current to cancel out high-order harmonic components that exceed the threshold. The flexible interconnect device combines spectrum data with the fundamental component of branch current to predict the temperature rise trend of the conductor based on the conductor thermal model, thus forming a thermal state estimate for future time periods. When the predicted temperature rise exceeds the safety threshold, the flexible interconnect device triggers the feedforward control mechanism to adjust the active power regulation and reactive power compensation, control the branch power flow, reduce the heat generation power, and maintain the conductor temperature within the set range.

7. The self-healing method for overhead power line faults in a distribution network as described in claim 6, characterized in that: The edge controller cyclically compares the lead thermal model, the synchronization phase-locked loop consistency index, and protection action records, adaptively corrects the compensation parameters of the flexible interconnect device, and writes the events into a self-healing knowledge base, including... Real-time conductor temperature data is obtained from the conductor thermal model and compared with the predicted temperature rise value. The temperature deviation is calculated. When the temperature deviation exceeds the preset threshold, the model parameters are corrected based on historical temperature data using the least squares method. Construct a synchronous phase-locked loop consistency index, calculate the real-time phase angle difference based on phasor synchronization deviation, and compare it with a preset threshold to determine phase synchronization. Collect protection action records of the protection device, statistically analyze the frequency and timing characteristics, and correlate them with temperature deviation and synchronous phase-locked loop consistency index; Based on the combined state of temperature deviation, synchronous phase-locked loop consistency index and protection action record, the active power compensation and reactive power compensation of the flexible interconnection device are adjusted by a proportional-integral-derivative controller, and the adjustment coefficient is set according to the distribution network response characteristics. The monitoring results and compensation adjustment actions are recorded as event logs and written to the self-healing knowledge base. The event logs include timestamps, operational status indicators, and compensation adjustment data.

8. A self-healing system for overhead distribution line faults, employing the self-healing method for overhead distribution line faults as described in any one of claims 1 to 7, characterized in that, include: The module includes a benchmark generation module, a sequence generation module, a coordination control module, a filter control module, and a parameter tuning module. The reference generation module is used to deploy synchronous phasor measurement units on both sides of the flexible interconnect device and the key segment switch to continuously collect voltage phasors and current phasors, generate a unified phasor reference through cloud-edge collaborative calculation, and broadcast it to the local controller. The sequence generation module is used by the edge coordination engine to calculate the power flow changes after loop closure based on a unified phasor reference and instantaneous topology state, and then write the action sequence into the trigger queues of the flexible interconnect device and the segmented switch. The coordination control module is used by the local controller to obtain the coordination coefficient by performing membership reasoning on phasor synchronization deviation and harmonic-thermal risk, and to control the pre-compensation of the flexible interconnection device and the closing timing of the sectionalizing switch based on the comparison result of the coordination coefficient and the preset threshold. The filtering control module is used for the line harmonic sensor to continuously upload spectrum data. The self-tuning filter in the flexible interconnection device suppresses high-order components in real time according to the harmonic distribution and pushes the temperature rise prediction value to the conductor thermal model. The parameter tuning module is used by the edge controller to cyclically compare the lead thermal model, synchronous phase-locked loop consistency index and protection action records, adaptively correct the compensation parameters of the flexible interconnection device, and write the events into the self-healing knowledge base.

9. 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 self-healing method for faults in overhead power distribution lines according to any one of claims 1 to 7.

10. 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 self-healing method for faults in overhead power distribution lines according to any one of claims 1 to 7.

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