Self-healing strategy adaptive adjustment method, system, device and medium for active power distribution network

Abstract

The application relates to the technical field of power distribution network fault processing, and discloses a self-healing strategy adaptive adjustment method, system, equipment and medium for an active power distribution network. The method can synchronously adjust protection setting values and load curves by using changed operation states and actual operation information of the power distribution network, determine a fault position by using fault detection information formed by protection devices operated by the updated protection setting values after a fault occurs, and further dynamically determine an isolation boundary by combining spatial distribution and off-grid capability of distributed power sources. After fault isolation, actual loads to be restored are determined by using the updated load curves, and power supply recovery is implemented. When recovery or isolation operation fails, corresponding isolation modes or power supply recovery modes are adjusted according to the isolation stage or the recovery stage of the failed equipment and the topology side opposite to the fault position, so that the adaptability, reliability and power supply recovery success rate of fault disposal of the active power distribution network are improved.

Description

Technical Field

[0001] This invention relates to the field of power distribution network fault handling technology, and in particular to a self-healing strategy adaptive adjustment method, system, device and medium for active power distribution networks. Background Technology

[0002] In active distribution networks, the grid-connected operation of distributed generation sources alters the distribution characteristics and direction of fault currents. Traditional distribution networks are typically single-source, radial structures with a constant power flow direction, simple protection and reclosing configurations, and easy fault self-healing. However, when high-penetration distributed generation sources are integrated into the distribution network, both the network structure and power flow direction change, affecting the original protection and reclosing functions and leading to protection maloperation, failure to operate, or reclosing failure.

[0003] After distributed power sources are connected, their impact on distribution network protection is essentially the effect of their output short-circuit current on different measuring points, either increasing or decreasing the voltage. For local feeder automation, if there is a distributed power source downstream of the fault point that is not disconnected from the grid, the residual voltage will affect the undervoltage tripping logic, preventing the switch from tripping normally. For centralized feeder automation, the influence of distributed power sources will cause alarm information in the intact sections to become inaccurate, leading to the master station misjudging the faulty section.

[0004] Currently, self-healing schemes for distributed faults in active distribution networks are difficult to automatically adjust with changes in operating mode. Changes in power direction are not automatically tracked, and load curves are out of sync with actual operating modes. Fault isolation strategies do not consider the potential safety hazards of islanded operation caused by the distribution of distributed power sources. They cannot effectively solve the problem of adaptive adjustment of self-healing strategies under the influence of distributed power source connection and disconnection in active distribution networks, which can easily lead to the failure of self-healing strategies in scenarios of distributed power source connection and disconnection, affecting the stable operation of the power grid. Summary of the Invention

[0005] In view of this, in order to solve the above-mentioned technical problems, the present invention provides a self-healing strategy adaptive adjustment method, system, device and medium for active power distribution networks.

[0006] The first aspect of this invention provides a self-healing strategy adaptive adjustment method for an active power distribution network, the method comprising: To obtain the operating status of distributed generation sources and distribution network operation information in active distribution networks; When the operating status of the distributed power source changes, the protection settings and load curves adapted to the current operating mode are updated according to the changed operating status and the distribution network operating information. When a fault occurs in the active distribution network, fault detection information generated by the protection device using the updated protection settings is obtained, the fault location is determined based on the fault detection information, and the fault isolation boundary is determined based on the fault location and the distribution of the distributed power sources, and fault isolation is performed based on the fault isolation boundary. Based on the updated load curve, power supply is restored to the non-faulty power loss area after fault isolation, and the self-healing scheme execution result is obtained. When the execution result of the self-healing scheme indicates that there is an execution failure, the fault isolation method or power supply restoration method is adjusted according to the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, and a secondary self-healing scheme is generated and executed.

[0007] In one example, updating the protection settings and load curves to adapt to the current operating mode based on the changed operating status and the distribution network operating information includes: Based on the changed operating status of each distributed power source, combined with the access status of each distributed power source and the current topology connection relationship of the distribution network, the current operating mode of the active distribution network and the protection devices affected by the change in operating status are determined. Based on the current operating mode, the protection setting value corresponding to the protection device is determined from the pre-established correspondence between different operating modes and protection settings, and the protection setting value is updated to the corresponding protection device; The power direction of each preset monitoring point before and after the change in the operating state is determined based on the power distribution network operation information, and the corresponding power data is adjusted according to the change in the power direction. The load curve is updated based on the adjusted power data and its corresponding changes in operating status.

[0008] In one example, obtaining fault detection information generated by the protection device using the updated protection settings, and determining the fault location based on the fault detection information, includes: Obtain protection action information generated by the protection device operating with the updated protection settings, and obtain power distribution terminal fault information within the fault period corresponding to the protection action information; Based on the equipment location and fault response direction corresponding to the protection action information and the power distribution terminal fault information, the protection action information and the power distribution terminal fault information are associated to obtain the fault detection information; Based on the correspondence between the fault detection information and the current topology connection relationship of the distribution network, candidate fault sections that match each fault response are determined; The target fault segment is determined based on the fault response status corresponding to each of the candidate fault segments, and the target fault segment is determined as the fault location.

[0009] In one example, determining the fault isolation boundary based on the fault location and the distribution of the distributed power sources, and performing fault isolation based on the fault isolation boundary, includes: Searching along the upstream and downstream directions of the fault location according to the topological connection relationship of the active distribution network, respectively, to determine the initial isolation boundary used to define the fault section; Based on the distribution of distributed power sources within the initial isolation boundary area and the off-grid capability of the corresponding distributed power sources, the initial isolation boundary is adjusted to obtain the fault isolation boundary. The isolation operation is performed according to the boundary switch corresponding to the fault isolation boundary control to isolate the fault in the area corresponding to the fault location.

[0010] In one example, adjusting the initial isolation boundary based on the distribution of distributed power sources within the initial isolation boundary area and the off-grid capability of the corresponding distributed power sources to obtain the fault isolation boundary includes: Identify the distributed power sources within the initial isolation boundary area, and determine whether each of the distributed power sources has independent off-grid capability; For distributed power sources with independent off-grid capability, control the corresponding distributed power source to perform off-grid execution, and determine whether the corresponding distributed power source can remain in the current isolation area based on the off-grid execution result; For distributed power sources that do not have independent off-grid capability or have failed to be off-grid, search outwards along the topology connection relationship of the corresponding distributed power source branch to find switches that can perform isolation operations, and adjust the current isolation boundary according to the found switches so that the power supply path of the corresponding distributed power source is isolated from the fault area. The off-grid status of the distributed power sources in the isolation area is re-determined based on the adjusted isolation area, and the current isolation boundary is adjusted based on the off-grid status until the adjusted isolation area meets the preset isolation conditions. The corresponding current isolation boundary is then determined as the fault isolation boundary.

[0011] In one example, based on the updated load curve, power restoration is performed on the non-faulty power-loss area after fault isolation to obtain the self-healing scheme execution result, including: Based on the updated load curve, determine the load to be restored in the non-fault power loss area under the current operating mode; Based on the topological connection between the non-faulty power loss area and the available power supply side in the distribution network, search for candidate power supply paths to restore the load to be restored; The power supply capacity of each candidate power supply path is checked according to the load to be restored, and the target power supply path is determined from the candidate power supply paths that meet the preset power supply capacity requirements. A power restoration operation is generated and executed based on the target power supply path, and the execution result of the self-healing scheme is obtained based on the execution status of the power restoration operation.

[0012] In one example, the step of adjusting the fault isolation method or power restoration method based on the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, and generating and executing a secondary self-healing scheme, includes: Based on the operation process corresponding to the execution failure, it is determined whether the device corresponding to the execution failure is in the fault isolation stage or the power restoration stage, and based on the topological connection relationship between the device corresponding to the execution failure and the fault location, the topological side of the device corresponding to the execution failure is determined. When the device corresponding to the execution failure is in the fault isolation stage, an alternative isolation location is searched along the corresponding direction according to the topology, and the fault isolation method is adjusted in combination with the distributed power status in the adjusted isolation area. When the device corresponding to the execution failure is in the power restoration phase, the corresponding non-fault power failure area is determined according to the topology, and the power restoration method is adjusted according to the load to be restored and the available power resources in the non-fault power failure area. The secondary self-healing scheme is generated based on the adjusted fault isolation method or power supply restoration method, and the secondary self-healing scheme is executed.

[0013] Secondly, the present invention also provides a self-healing strategy adaptive adjustment system for an active power distribution network, the system comprising: The information acquisition module is used to acquire the operating status of distributed generation in the active distribution network and the operation information of the distribution network. The setting update module is used to update the protection settings and load curves that are adapted to the current operating mode based on the changed operating state and the distribution network operating information when the operating state of the distributed power source changes. The fault isolation module is used to acquire fault detection information generated by the protection device using the updated protection settings when a fault occurs in the active distribution network, determine the fault location based on the fault detection information, determine the fault isolation boundary based on the fault location and the distribution of the distributed power sources, and perform fault isolation based on the fault isolation boundary. The self-healing scheme execution module is used to restore power supply to the non-faulty power loss area after fault isolation based on the updated load curve, and obtain the self-healing scheme execution result. The secondary self-healing scheme execution module is used to generate and execute a secondary self-healing scheme when the execution result of the self-healing scheme indicates that there is an execution failure, based on the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, by adjusting the fault isolation method or power supply restoration method.

[0014] Thirdly, the present invention also provides an electronic device, the electronic device including a memory and a processor, the memory storing a computer program, the computer program being executed by the processor causing the processor to perform the steps of the self-healing strategy adaptive adjustment method for active power distribution networks as described in the first aspect.

[0015] Fourthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the steps of the self-healing strategy adaptive adjustment method for active power distribution networks as described in the first aspect.

[0016] As can be seen from the above technical solutions, when a distributed power source undergoes grid connection, off-grid operation, or a change in operating mode, this invention can synchronously adjust the protection settings and load curves using the changed operating status and actual operating information of the distribution network, ensuring that the action basis of the protection device and the load data used for power restoration correspond to the current operating mode. After a fault occurs, the fault detection information generated by the protection device operating with the updated protection settings is used to determine the fault location, and the isolation boundary is dynamically determined by combining the spatial distribution and off-grid capability of the distributed power source, thereby reducing the impact of reverse feed-in or residual power supply of the distributed power source on the fault location and isolation process. After fault isolation, the updated load curve is used to determine the actual load to be restored and power restoration is implemented. If the restoration or isolation operation fails, the corresponding isolation method or power restoration method is adjusted accordingly based on the isolation stage or restoration stage of the failed device and its topological position relative to the fault location. Therefore, this technical solution enables the protection setting, fault location, isolation and recovery processes to be continuously linked with the distributed power source in and out of the grid, reducing self-healing failures caused by fixed protection settings, lagging load data and mismatch between fixed secondary handling strategies and actual operating modes, and improving the adaptability, reliability and power supply restoration success rate of active distribution network fault handling. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the 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.

[0018] Figure 1 An application environment diagram of an adaptive adjustment method for a self-healing strategy in an active power distribution network provided in an embodiment of the present invention; Figure 2 A flowchart illustrating an adaptive adjustment method for a self-healing strategy in an active power distribution network, provided as an embodiment of the present invention. Figure 3 This is a schematic diagram of the structure of an adaptive adjustment system for a self-healing strategy in an active power distribution network, provided by an embodiment of the present invention. Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The self-healing strategy adaptive adjustment method for active distribution networks provided in this application embodiment can be applied to, for example... Figure 1The application environment shown is illustrated. Terminal 101 communicates with server 102 via a network. A data storage system can store the data that server 102 needs to process. The data storage system can be integrated onto server 102, or it can be located in the cloud or on another network server. Terminal 101 or server 102 executes an adaptive adjustment method for self-healing strategy of an active distribution network. The method includes: acquiring the operating status of distributed generation in the active distribution network and distribution network operating information; when the operating status of distributed generation changes, updating the protection settings and load curves adapted to the current operating mode according to the changed operating status and distribution network operating information; when a fault occurs in the active distribution network, acquiring fault detection information generated by the protection device using the updated protection settings, determining the fault location according to the fault detection information, determining the fault isolation boundary according to the fault location and the distribution of distributed generation, and performing fault isolation according to the fault isolation boundary; restoring power supply to the non-fault-affected power loss area after fault isolation based on the updated load curve, and obtaining the self-healing scheme execution result; when the self-healing scheme execution result indicates that there is an execution failure, adjusting the fault isolation method or power supply restoration method according to the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, and generating and executing a secondary self-healing scheme.

[0021] Terminal 101 can be, but is not limited to, various personal computers, laptops, smartphones, and tablets.

[0022] Server 102 can be a standalone physical server, a server cluster or distributed system consisting of multiple physical servers, or a cloud server that provides cloud computing services.

[0023] like Figure 2 As shown in the embodiments of this application, an adaptive adjustment method for the self-healing strategy of an active distribution network is provided, which is applied to... Figure 1 Taking terminal 101 or server 102 as an example, the explanation includes the following steps S1 to S5. Wherein: Step S1: Obtain the operating status of distributed generation in the active distribution network and the operation information of the distribution network.

[0024] Distributed power sources can include distributed photovoltaic (PV) systems, decentralized or small-scale wind power generation equipment, and energy storage systems, which are connected to the distribution network and can alter the power distribution of the distribution network. Operating status characterizes the actual operating relationship between the distributed power source and the active distribution network at the current moment, and can include one or more of the following: grid-connected status, off-grid status, power-limited operation status, current output, and operating mode. For energy storage systems, operating modes can further include charging and discharging states.

[0025] Distribution network operation information can include information such as voltage, current, active power, reactive power, power direction, current status of lines and switches, and current topological connections of the active distribution network. Among these, the operating status of distributed generation sources is used to characterize the power source-side status that causes changes in the distribution network's operating mode, and the distribution network operation information is used to reflect the actual operating results of these status changes on the distribution network side.

[0026] In one specific implementation, intelligent monitoring terminals can be installed at locations such as the distributed power source grid connection point, line sectionalizing switches, tie switches, and feeder outlets. The grid connection status of the distributed power source can be obtained by anti-islanding protection devices or status monitoring modules at the grid connection point; operating parameters such as voltage, current, and power can be obtained by feeder terminal units (FTUs), distribution terminals (DTUs), or intelligent distributed terminals. The intelligent monitoring terminal can preprocess and locally cache the collected data, and actively upload status change information when a change in operating status is detected.

[0027] Step S2: When the operating status of the distributed power source changes, update the protection settings and load curves to adapt to the current operating mode based on the changed operating status and distribution network operating information.

[0028] Among them, the operating status of distributed power sources can be monitored by collecting real-time operating information such as grid connection status, operating mode, output power, and grid connection switch status.

[0029] When a change is detected in the grid-connected status, off-grid status, operating mode, or output status of a distributed power source relative to the previous detection cycle, it is determined that the operating status of the distributed power source has changed, and the subsequent protection settings and load curve update process are triggered.

[0030] In an exemplary embodiment, when the operating state of at least one distributed generation source changes, adaptive updates can be performed in two directions: protection setting and operation data maintenance. Specifically, the protection setting direction determines the current operating mode and affected protection devices based on the changed operating state of the distributed generation source and the current topology connections, and enables the corresponding protection devices to operate with protection settings matching the current operating mode. The operation data maintenance direction adjusts the power data based on the power direction changes at each monitoring point in the distribution network before and after the operating state change, ensuring that the load curve synchronously reflects the actual power flow changes caused by the disconnection of distributed generation sources from the grid.

[0031] The horizontal axis of the load curve represents the monitoring time, and the vertical axis represents the integrated and adjusted power value for the corresponding monitoring point. Each monitoring point can generate an independent load curve. The distribution network operation and dispatch center can aggregate the load curves of all monitoring points and combine them with the topological connection relationship to obtain overall operation data support. Specifically, when distributed generation switches from off-grid to grid-connected status, the power direction of the corresponding monitoring point will reverse, and the sign of the power value recorded on the original load curve also needs to be adjusted synchronously with the power direction to ensure that the load curve can accurately reflect the actual active and reactive power distribution of the current distribution network.

[0032] Therefore, the updated protection settings are used by the subsequent protection devices to generate fault detection information, and the updated load curves are used to determine the loads to be restored in the non-fault power loss areas and to restore power supply. This ensures that both the updated protection settings and the updated load curves participate in the subsequent self-healing process, rather than forming independent processing results.

[0033] The current operating mode does not refer to the working mode of a single distributed power source, but rather to the operating mode of the distribution network as a whole, formed by the actual operating status of each distributed power source, the location of the distributed power source connection, and the current topology of the distribution network. This limitation avoids relying solely on a single grid connection / disconnection signal for strategy switching, ensuring that subsequent protection settings and load curves correspond to the actual electrical connection status.

[0034] Step S3: When a fault occurs in the active distribution network, obtain the fault detection information generated by the protection device using the updated protection settings, determine the fault location based on the fault detection information, determine the fault isolation boundary based on the fault location and the distribution of distributed power sources, and perform fault isolation based on the fault isolation boundary.

[0035] Among them, it is possible to determine whether a fault has occurred in the active distribution network by collecting information on the action of protection devices, the status of fault indicators, and the operating information such as current, voltage, and power direction collected by the distribution terminal.

[0036] When a protection device is activated, a fault indicator is triggered, or abnormal changes occur in the electrical parameters of the line that meet the preset fault criteria, a fault is determined to have occurred in the active distribution network, and the fault location, isolation, and recovery process begins.

[0037] If no abnormal information that meets the fault criteria is detected, it is assumed that no fault has occurred in the current active distribution network. The network operation status will continue to be monitored, the current operation mode will be maintained, and the fault self-healing strategy will not be implemented.

[0038] This includes a protection device that performs fault detection and protection criterion judgment according to the new protection settings after the aforementioned protection settings have been updated and confirmed to be effective. Simultaneously, the protection device operating with the updated protection settings generates protection action information to determine fault detection information, which may also include fault indicator action information, overcurrent information, and direction information reported by the feeder terminal.

[0039] Subsequently, the approximate range of the fault is initially located using fault detection information. Then, combined with the current topology of the distribution network, the range is gradually narrowed down along the transmission path of the fault current to finally determine the fault location. The initial range of fault isolation is then determined by combining the fault location with the location of the distributed power source. The boundary is then adjusted step by step according to the actual off-grid capability of the distributed power source within the range to finally obtain a fault isolation boundary that takes into account both the reliability of fault isolation and the continuity of power supply to non-faulty areas. Finally, the switch at the control boundary is tripped to complete the electrical isolation between the fault area and the normal operating area.

[0040] Step S4: Based on the updated load curve, restore power supply to the non-faulty power-loss areas after fault isolation to obtain the self-healing scheme execution results.

[0041] After fault isolation is completed, non-faulty power loss areas that are still in a state of power loss but do not belong to the fault area are determined based on the final fault isolation boundary. Since the grid connection and disconnection of distributed power sources may have changed the actual load and power flow direction before and after the fault, the power data of the corresponding non-faulty power loss areas under the current operating mode can be extracted from the updated load curve. Based on this, the loads to be restored are determined, and power is restored to the loads to be restored, thus obtaining the execution result of the self-healing scheme.

[0042] The execution result of this self-healing scheme can at least characterize whether the power restoration was successful, and identify the corresponding failed devices and operations when failures occur, thus providing a basis for subsequent adjustments to the self-healing strategy. If all operations of a self-healing cycle are executed normally and power is restored to all non-faulty power-loss areas, the current self-healing process ends directly; if there are operational failures, the secondary self-healing processing logic is initiated.

[0043] Step S5: When the self-healing scheme execution result indicates that there is an execution failure, adjust the fault isolation method or power supply restoration method according to the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, and generate and execute a secondary self-healing scheme.

[0044] The self-healing phase includes at least a fault isolation phase and a power restoration phase. The fault isolation phase includes fault location determination, isolation boundary determination, and isolation operations; the power restoration phase includes determination of non-fault power loss areas, power supply path search, power supply capacity verification, and power restoration operations.

[0045] The confirmation of fault isolation completion can be used as the dividing line between the two phases. The power restoration phase does not begin until the fault isolation has been confirmed as complete.

[0046] During the self-healing process, the execution feedback of each operation step can be continuously monitored. If no successful feedback is received within the specified time, or if failure feedback such as switch failure, communication failure, or operation lockout is received, an execution failure is determined, and the failure time, device number, topological side of the failed device relative to the fault location, current self-healing stage, and cause of failure are recorded.

[0047] In this way, execution failure is not just a simple success / failure indicator, but a failure characteristic that can form the basis for subsequent adjustments to fault isolation or power restoration methods.

[0048] Topology identification can be determined based on the real-time topology connection relationship between the failed device and the fault location.

[0049] For example, the direction from the substation or main power supply side along the power supply topology to the fault location can be used to determine the upstream side of the fault; the direction extending from the fault location to the end of the line or the load side can be used to determine the downstream side of the fault.

[0050] Subsequently, based on the two dimensions of the stage of failure and topology, different adaptive adjustment strategies are matched. Without directly triggering manual maintenance, the self-healing strategy can be adjusted online, minimizing manual intervention and improving the efficiency of power restoration in non-faulty areas.

[0051] It should be noted that the above technical solution can synchronously adjust the protection settings and load curves using the changed operating status and actual operating information of the distribution network when the distributed power source is connected to the grid, disconnected from the grid, or changes its operating mode. This ensures that the action basis of the protection device and the load data used for power restoration correspond to the current operating mode. After a fault occurs, the fault detection information generated by the protection device operating with the updated protection settings is used to determine the fault location. Furthermore, the isolation boundary is dynamically determined by combining the spatial distribution and off-grid capability of the distributed power source, thereby reducing the impact of reverse feed-in or residual power supply of the distributed power source on the fault location and isolation process. After fault isolation, the updated load curve is used to determine the actual load to be restored and power restoration is implemented. If the restoration or isolation operation fails, the corresponding isolation method or power restoration method is adjusted according to the isolation stage or restoration stage of the failed device and its topological position relative to the fault location. Therefore, this technical solution enables the protection setting, fault location, isolation and recovery processes to be continuously linked with the distributed power source in and out of the grid, reducing self-healing failures caused by fixed protection settings, lagging load data and mismatch between fixed secondary handling strategies and actual operating modes, and improving the adaptability, reliability and power supply restoration success rate of active distribution network fault handling.

[0052] In some embodiments, updating protection settings and load curves to adapt to the current operating mode based on the changed operating status and distribution network operating information includes: Step S201: Based on the changed operating status of each distributed power source, combined with the access status of each distributed power source and the current topology connection relationship of the distribution network, determine the current operating mode of the active distribution network and the protection devices affected by the change in operating status.

[0053] The current operating mode is used to characterize the actual power supply relationship formed between power sources, lines, and loads in the active distribution network after the operating status of distributed generation changes. Since the connection of distributed generation changes the power flow distribution and fault current propagation path in the distribution network, when distributed generation is connected to the grid, disconnected from the grid, or changes its operating mode, it is necessary to determine the current operating mode by combining the changes in the state of the distributed generation and the current topology of the distribution network.

[0054] Specifically, the first step is to acquire the status information corresponding to the distributed power sources whose operating states have changed. This status information can include the distributed power source's grid-connected status, off-grid status, output status, and operating mode. For example, when a distributed photovoltaic system switches from grid-connected to off-grid operation, it indicates that the distributed power source has exited the current power distribution network; when an energy storage device switches from charging to discharging, it indicates that the device has changed from a load state to a power supply support state.

[0055] Furthermore, the connection location of each distributed power source in the distribution network is determined based on its connection status. Connection status can include the distributed power source's connection node, its feeder, connection voltage level, and the status of the corresponding grid-connected switch. By determining the connection location of the distributed power source, the power supply area that may be affected by changes in its operating status can be identified.

[0056] Furthermore, the actual power supply relationship after the change in the status of distributed generation is determined based on the current topology of the distribution network. The topology can include the status of line connections, switch status, and interconnection equipment status.

[0057] For example, when a distributed power source switches from grid-connected to off-grid status, based on its access nodes and current line connections, it can be determined which power supply paths will take over the original load after the distributed power source is removed; when the tie switch is closed or opened, it can be determined whether a new electrical connection relationship is formed between power supply areas based on the new topology connection relationship.

[0058] Based on the aforementioned operating status of distributed generation sources, their connection locations, and the distribution network topology, the current operating mode can be determined. The current operating mode is not the operating status of a single distributed generation source, but rather an operating status formed by the combined status of multiple distributed generation sources and the actual connection relationships within the distribution network. It characterizes the power supply relationships between various power source nodes, line nodes, and load nodes in the current distribution network.

[0059] Furthermore, based on the determined current operating mode, the protection devices affected by the change in operating status are identified. Specifically, based on the location of the distributed power source whose status has changed, the current distribution network topology can be searched for lines and protection devices that have an electrical connection with that distributed power source. If the line corresponding to a certain protection device is located on the power supply path of the distributed power source, or if the change in the status of the distributed power source may cause changes in the magnitude, direction, or protection coordination relationship detected by the protection device, then that protection device is identified as an affected protection device.

[0060] For example, when a distributed power source switches from grid-connected to off-grid status, the reverse power flow on its corresponding feeder may disappear, causing the protection criteria of the directional protection device associated with that feeder to change; when a distributed power source returns to grid connection from off-grid status, it may resume supplying fault current to the fault area, therefore, the line protection device connected to it needs to rematch the protection parameters.

[0061] Finally, the set of protection devices affected by changes in operating status is obtained, and the protection settings of the protection device set are updated to match the current operating mode.

[0062] Step S202: Based on the current operating mode, determine the protection setting value corresponding to the protection device from the pre-established correspondence between different operating modes and protection settings, and update the protection setting value to the corresponding protection device.

[0063] In one exemplary embodiment, a setpoint parameter library can be pre-established, storing corresponding protection settings according to different combinations of distributed power source states and distribution network operation modes. The setpoint parameters may include one or more of the following: the operating current setting of the directional overcurrent protection, the operating time setting, the sensitivity angle of the directional element, the voltage blocking value, and the zero-sequence current setting.

[0064] For each distributed power source access point, its operating state can be represented by state variables, for example: Indicates an offline status; Indicates grid connection status; This indicates a power-limited operating state.

[0065] When there is an active distribution network When there are multiple distributed power sources, a state vector can be formed according to a preset device sequence:

[0066] in, Indicates the first The current operating status of each distributed power source can be determined. A corresponding status combination code can be generated based on the status vector, and this code is used as one of the indices in the setting parameter library. During operation, the current status combination code is generated based on the real-time detected status of each distributed power source, and the basic protection settings are retrieved from the setting sub-table corresponding to the current voltage level, connection location, and distributed power source type.

[0067] Based on this, the basic protection settings can be corrected according to changes in the current topology relative to the basic operating mode. For example, a topology correction factor can be used:

[0068] in, Represents the topology correction factor; Indicates the influence coefficient of the contact switch status; Indicates the influence coefficient of line segmentation; This represents the load level influence coefficient.

[0069] When the tie switch changes from open to closed, the system's equivalent impedance typically decreases because the previously relatively independent power supply branches form a new electrical connection. It can be greater than 1, for example, 1.05 to 1.20; when the tie switch changes from closed to open, the equivalent impedance of the system usually increases. It can be less than 1, for example, 0.80 to 0.95. It can be determined based on the change in total line impedance caused by changes in line segmentation; It can be determined based on the change in the current load rate relative to the baseline load rate.

[0070] System equivalent impedance This represents the Thevenin equivalent impedance as observed from the installation point of the corresponding protection device towards the system side. In radial distribution networks, it can be calculated based on the short-circuit capacity.

[0071] in, Indicates the system's rated voltage. This indicates the system short-circuit capacity at the protection installation point.

[0072] For complex topologies, a positive-sequence impedance network can be constructed based on the current topology, and the impedance of each node can be determined using the node impedance matrix. Alternatively, system disturbances such as load switching and changes in distributed power output can be utilized to obtain the equivalent impedance based on the voltage and current changes before and after the disturbance, and this equivalent impedance can be used for online verification of the equivalent impedance obtained based on topology calculation.

[0073] The operating current setting can be adjusted according to the following formula:

[0074] in, This indicates the operating current setting corresponding to the basic operating mode. This indicates the adjusted operating current setting corresponding to the current operating mode. This represents the equivalent impedance of the system under the basic operating mode. This represents the equivalent impedance of the system under the current operating mode. This represents the reliability coefficient, which can be taken as 1.1 to 1.3.

[0075] For the action time constant:

[0076] in, This represents the time setpoint for the basic motion. This indicates the adjusted motion time setpoint. The time-matching reliability coefficient can be taken as 0.85 to 1.15.

[0077] For voltage blocking values:

[0078] in, Indicates the base voltage blocking value. This indicates the adjusted voltage lockout value.

[0079] The zero-sequence current setting can be adjusted based on the total system-to-ground capacitance corresponding to the current topology.

[0080] in, This represents the basic zero-sequence current setting. This indicates the adjusted zero-sequence current setting. This represents the total system-to-ground capacitance under the current topology. This represents the total system-to-ground capacitance corresponding to the basic operating mode.

[0081] The sensitivity angle of the directional element can be adjusted based on the equivalent impedance angle of the currently protected line. The sensitivity angle of the directional element is denoted as... The impedance angle of the protected line is denoted as It can make:

[0082] as well as:

[0083] in, Indicates the reactance of the protected line. This indicates the resistance of the protected circuit.

[0084] When a line consists of multiple segments, its equivalent line impedance can be expressed as:

[0085] in, and They represent the first The resistance and reactance of each circuit segment, This indicates the number of line segments. After determining the equivalent impedance of the line under the current topology, the adjusted sensitivity angle is determined based on its impedance angle, so that the maximum sensitivity direction of the directional element is adapted to the short-circuit impedance characteristics of the current line.

[0086] Through the above processing, the state combination is used to determine the basic settings, and the current topology and load status are further used to correct the basic settings, so that the final protection settings not only correspond to the grid connection and disconnection status of distributed power sources, but also reflect the actual topology changes.

[0087] In addition, the determined protection settings are sent to the temporary storage area of ​​the corresponding protection device. After receiving the data, the protection device performs integrity checks, permissible setting range checks, and consistency checks between different setting parameters. Integrity checks are used to determine whether bit errors or data loss occurred during transmission; range checks are used to determine whether each protection setting is within the permissible parameter range of the protection device; and consistency checks are used to prevent conflicting action relationships between different protection parameters.

[0088] After successful verification, the protection device returns a confirmation message, and the self-healing strategy control center then sends a setting activation command. The protection device writes the new setting from the temporary storage area to the operating parameter area and reads back the updated operating parameters for further confirmation. If writing or reading fails, the protection setting before the update is restored, and a setting update failure message is returned to the control center.

[0089] By adopting the above method, the protection device can actually operate according to the updated protection settings when a subsequent fault occurs. Therefore, when the protection device generates protection action information, this protection action information can reflect the current operating mode after the change in the operating state of the distributed power source, providing a fault response basis that matches the current operating state for subsequent fault location determination.

[0090] Step S203: Determine the power direction of each preset monitoring point before and after the change in operating status based on the power distribution network operation information, and adjust the corresponding power data according to the change in power direction.

[0091] The preset monitoring points can be set at distributed power grid connection points, line sectionalizing switches, tie switches, and feeder outlets. The intelligent monitoring terminal can acquire active power P, reactive power Q, voltage phasor U, and current phasor I at a sampling interval of 20ms (power frequency cycle).

[0092] The power factor angle can be calculated based on the voltage phase angle and the current phase angle:

[0093] in, Indicates the voltage phase angle. This indicates the phase angle of the current.

[0094] When the power factor corresponding to the power factor angle is positive, it can be determined as a preset positive power flow; when the power factor corresponding to the power factor angle is negative, it can be determined as a reverse power flow. In one specific specification, with the bus as the reference node, the flow from the bus side to the load side is defined as the positive direction, and the flow from the distributed power source side back to the bus side is defined as the reverse direction.

[0095] You can also directly use active power The sign of the symbol is used to determine the power direction.

[0096] This indicates that power is flowing in the forward direction;

[0097] This indicates that power flows in the reverse direction.

[0098] When the operating status of the distributed power source changes, causing the power direction at the monitoring point to change from positive to negative, or from negative to positive, the symbol of the power data is adjusted synchronously, and the time of the direction change and the power value before and after the change are recorded, so that the power symbol in the subsequent load curve can correspond to the actual physical flow direction.

[0099] To reduce the impact of sampling noise and random fluctuations near zero power on power direction determination, a moving average can be applied to the instantaneous power values ​​over 3 to 5 consecutive power frequency cycles, i.e., within a range of approximately 60ms to 100ms.

[0100] When the absolute value of the filtered power is less than 1% to 2% of the rated power, the power data can be zeroed out to avoid frequent reversals of the positive and negative directions caused by measurement noise when the output of the distributed power source is very small or close to zero power exchange.

[0101] When the measured power exceeds the range of the monitoring terminal, the power value can be limited to the range boundary, and an over-limit indicator can be added. The uploaded power data can also carry a timestamp and a data validity indicator to distinguish normal sampling data, filtered data, over-limit data, and transient data at the moment of direction change.

[0102] Through the above processing, the subsequent load curve uses not only power data after simply changing the sign, but also power data that has been processed in combination with directional status, data quality and occurrence time, thereby reducing the impact of incorrect directional switching on the load curve and subsequent power transfer calculations.

[0103] Step S204: Update the load curve based on the adjusted power data and its corresponding changes in operating status.

[0104] Specifically, the moment when the power direction changes can be determined first on the time axis of the load curve. And associate the corresponding distributed power supply operating status change events with Related.

[0105] by To establish a time boundary, power data before and after the directional change are stored in the load curve according to a unified directional reference. This allows the load curve to record not only the power magnitude but also the power flow direction and the corresponding operating status of the distributed power source. For the display interface, different display indicators can be used to distinguish different operating states, but the display method itself is not a necessary limitation for updating the load curve.

[0106] The updated load curves can continue to be used for subsequent fault analysis and power restoration. For example, after a fault occurs, the actual load that needs to be restored to each non-faulty power loss area can be determined based on the latest load curve corresponding to the fault time, instead of continuing to use the historical load values ​​saved before the distributed power source was disconnected from the grid. At the same time, the consistency between the latest operating mode reflected by the load curve and the operating mode corresponding to the current protection settings can be checked.

[0107] Therefore, the changes in power flow direction caused by distributed generation going to and from the grid can be directly transmitted to the subsequent self-healing recovery stage, reducing the deviation in the judgment of transfer capacity caused by the inconsistency between load data and actual operating mode.

[0108] In some embodiments, acquiring fault detection information generated by a protection device using updated protection settings, and determining the fault location based on the fault detection information, includes: Step S301: Obtain the protection action information generated by the protection device operating with the updated protection settings, and obtain the power distribution terminal fault information within the fault period corresponding to the protection action information.

[0109] After a fault occurs, fault responses from different sources can be merged according to device number and timestamp. Before merging, the communication status and data validity of the corresponding terminal can be checked first. Data with abnormal communication or that is obviously out of the valid range can be marked as abnormal to avoid directly using unreliable information to determine the fault location.

[0110] Protection action information reflects whether the protection device operating with the current protection settings has met the operating conditions. Subsequently, fault current, fault voltage, and opening / closing status information collected from each distribution terminal during the fault period are acquired. The fault information uploaded by the distribution terminals is also matched with the protection action information according to a time window, including only valid data within a predetermined time window before and after the fault occurrence in the analysis scope, excluding invalid data interference from non-fault periods, to obtain the distribution terminal fault information. The distribution terminal fault information is used to characterize the overcurrent state and fault response direction at the corresponding location.

[0111] Step S302: Based on the equipment location and fault response direction corresponding to the protection action information and the power distribution terminal fault information, associate the protection action information and the power distribution terminal fault information to obtain fault detection information.

[0112] Among them, the protection action information is used to characterize the action of the protection device operating with the updated protection settings after a fault occurs, and the distribution terminal fault information is used to characterize the fault response collected by the fault detection equipment installed at the line node or switch position.

[0113] The protection action information may include the protection device number, action time, action type, and corresponding protection area; the power distribution terminal fault information may include fault indicator action information, overcurrent information collected by the feeder terminal, direction information, and corresponding collection location.

[0114] Since distributed generation in an active distribution network may change the direction of fault current flow, the direction of fault response needs to be considered when correlating fault information from different sources.

[0115] Specifically, firstly, based on the equipment identification of the protection device and the distribution terminal, the spatial location corresponding to each fault information is determined, and each fault information is mapped to the corresponding node or line segment in the current topology of the distribution network.

[0116] Then, based on the current direction detected by each device when the fault occurs, the protection action direction, and the topological relationship between the device and the fault area, the fault response direction corresponding to each fault information is determined.

[0117] For example, when a distributed generation (DG) is connected to the end of a feeder, after a fault occurs, the DG may provide a reverse fault current to the fault point. In this case, the feeder terminal located on the DG side may detect reverse overcurrent information. Therefore, when correlating fault information, the source of the fault cannot be simply determined according to the current direction in a traditional single-source distribution network. Instead, a comprehensive analysis combining the location of the DG connection and the direction of the fault response is required.

[0118] Furthermore, protection action information and distribution terminal fault information that are adjacent in location, have similar fault occurrence times, and match fault response directions are correlated to form fault detection information. Fault detection information may include: a set of fault-responding devices, the fault response direction corresponding to each device, the correspondence between each device and the distribution network topology nodes, and the fault response occurrence time of each device.

[0119] Step S303: Based on the correspondence between the fault detection information and the current topology connection relationship of the distribution network, determine the candidate fault sections that match each fault response.

[0120] The current topology connection relationship of the distribution network is used to describe the actual connection status between lines, switches, nodes and distributed power sources.

[0121] Specifically, each fault response can be mapped to the distribution network topology based on the location of each fault response device in the fault detection information.

[0122] For example, the protection action information generated by a certain protection device can determine the protection range of that protection device; the overcurrent and direction information generated by a certain feeder terminal can determine the line section where the terminal is located and the corresponding power supply direction.

[0123] Furthermore, based on the topological relationship between each fault response device, line segments located within the intersection area of ​​the protection ranges of different fault response devices are searched, and line segments that meet the fault response conditions are identified as candidate fault segments.

[0124] Specifically, when a fault occurs in a certain section of the line, the feeder can be divided according to the current topology. A candidate fault section with adjacent switches as the boundary.

[0125] Step S304: Determine the target fault section based on the fault response status of each candidate fault section, and determine the target fault section as the fault location.

[0126] After obtaining multiple candidate fault sections, the target fault section can be further determined based on the fault response of each candidate fault section. Specifically, a topological correlation matrix between the section and the monitoring point can be established. Among them, the topological correlation matrix The matrix element a is used to characterize whether each monitoring point can detect the fault in the corresponding section. {ij} This represents the association between the i-th candidate fault segment and the j-th monitoring point. When the i-th candidate fault segment fails, if the i-th monitoring point can detect a fault response that meets the action conditions according to the current topology, then a {ij} =1, otherwise a {ij} =0. Subsequently, a fault information column vector B is formed by arranging the overcurrent / direction signals sent by each monitoring point corresponding to each candidate fault section according to the monitoring point number. The fault information column vector B is used to characterize whether the corresponding monitoring point has detected a fault response that meets the characteristics. If monitoring point j has detected a fault response that meets the requirements, the fault response (such as an overcurrent signal) is encoded, and the corresponding element b in B is used to encode the fault response. j Let bj be the encoded value of the fault response. A higher fault response level results in a higher encoded value. If no fault response meeting the requirements is detected, bj is recorded as 0. Finally, the topological association matrix A is matched with the fault information column vector B, and the fault criterion vector is calculated using matrix multiplication. This yields:

[0127] in, This represents the fault criterion vector corresponding to each candidate fault section. Element C is used to characterize the degree to which each candidate fault segment matches the current fault detection result. i The larger the value of , the higher the probability that the i-th candidate fault segment is the actual fault segment. The candidate fault segment corresponding to the element with the largest value in the criterion vector is selected and determined as the final target fault segment.

[0128] When the criteria results of multiple candidate fault segments are the same, the scope can be further narrowed by combining the current topology: the segment closest to the upstream is selected as the target fault segment.

[0129] The final fault location can be represented by the fault feeder, the fault section, and the upstream and downstream boundary switches of that section, and used as the starting point for subsequent isolation boundary searches.

[0130] In some embodiments, determining a fault isolation boundary based on the fault location and the distribution of distributed power sources, and performing fault isolation based on the fault isolation boundary, includes: Step S311: Search along the upstream and downstream directions of the fault location according to the topological connection relationship of the active distribution network to determine the initial isolation boundary used to limit the fault section.

[0131] Among them, the target fault section can be used as the search center, and the switch search can be performed in the upstream and downstream directions along the real-time topology connection relationship.

[0132] Upstream, the switch closest to the target fault section and possessing both breaking and control capabilities is designated as the upstream initial disconnecting switch; downstream, the switch closest to the target fault section and possessing both breaking and control capabilities is designated as the downstream initial disconnecting switch. The set of nodes and lines defined by the upstream and downstream initial disconnecting switches constitutes the initial isolation area. "Possessing breaking capability" means that the corresponding switch can perform a tripping operation for fault isolation under its current operating state.

[0133] Step S312: Adjust the initial isolation boundary according to the distribution of distributed power sources within the initial isolation boundary area and the off-grid capability of the corresponding distributed power sources to obtain the fault isolation boundary.

[0134] Among them, a distribution network topology database can be pre-established to record the electrical connection relationships between nodes, switches, and lines, as well as the grid connection point location, feeder, capacity, and type of each distributed power source, and associate the distributed power source as the attribute of the corresponding grid connection node with the topology structure.

[0135] After determining the initial isolation area, the nodes and lines contained in the area are matched with the locations of distributed power source access to determine whether there is a distributed power source there.

[0136] Independent off-grid capability can be understood as the distributed power source branch having a grid-connected switch capable of independently disconnecting its electrical connection with the distribution network, and possessing anti-islanding protection or corresponding control capabilities to respond to off-grid control. In one specific implementation, if the corresponding distributed power source can reliably disconnect from the grid within a specified time, such as 2 seconds, it can be considered to have the conditions to be independently handled within the current isolation area.

[0137] Furthermore, based on the distribution of distributed power sources within the initial isolation boundary and their respective off-grid capabilities, the initial isolation boundary is adjusted to obtain a fault isolation boundary. This includes: identifying the distributed power sources within the initial isolation boundary and determining whether each distributed power source has independent off-grid capability; for distributed power sources with independent off-grid capability, controlling them to perform off-grid operation and determining whether they can remain within the current isolation area based on the off-grid execution result; for distributed power sources without independent off-grid capability or that have failed to off-grid, searching outwards along the topology connection of the branch where the corresponding distributed power source is located for switches capable of performing isolation operations, and adjusting the current isolation boundary based on the found switches to isolate the power supply path of the corresponding distributed power source from the fault area; redetermining the off-grid status of the distributed power sources in the isolation area based on the adjusted isolation area, and continuing to adjust the current isolation boundary based on the off-grid status until the adjusted isolation area meets the preset isolation conditions, and then determining the corresponding current isolation boundary as the fault isolation boundary.

[0138] For distributed power sources with independent off-grid capability, an off-grid command can be sent to the corresponding grid-connected control device or anti-islanding protection device, and the off-grid execution result can be awaited. When off-grid is successful, although the distributed power source is still located within the isolation area in terms of topology, its power supply path has been cut off, and it no longer forms a power source that continuously supplies power to the fault area. Therefore, the current boundary can be retained without further expanding the isolation range.

[0139] This approach avoids unconditionally expanding the power outage area simply because there are distributed power sources in the isolation area, and allows the adjustment of the isolation boundary to take into account both reliable fault isolation and the power supply range of non-faulty areas.

[0140] For distributed generation that does not have independent off-grid capability or cannot be confirmed to have disconnected from the distribution network after off-grid operation, the next operable switch can be searched outward along the topological connection relationship of its branch, and the searched switch can be used as a new candidate boundary switch.

[0141] After each boundary adjustment is completed, the adjusted isolation zone is re-established, and the grid connection status of each distributed power source within it is re-checked. If there are still distributed power sources that cannot be reliably disconnected from the grid and whose power supply paths remain electrically connected to the fault area, the above search and boundary adjustment process continues.

[0142] The preset isolation conditions are: there are no grid-connected distributed power sources in the isolation area that can still continuously supply power to the fault area, that is, all distributed power sources located in the isolation area have been reliably disconnected from the grid, or their power supply paths have been disconnected from the fault area through the isolation boundary adjustment.

[0143] Step S314: Perform isolation operation according to the boundary switch corresponding to the fault isolation boundary control to isolate the fault in the area corresponding to the fault location.

[0144] Once the fault isolation boundary is determined, the isolation operation sequence can be formed based on the topological side of each boundary switch relative to the fault location.

[0145] In one specific embodiment, a downstream-to-upstream isolation sequence can be adopted. Downstream isolation is performed first to preferentially cut off the feed-in paths that may be formed by distributed power sources and loads downstream of the fault point; then upstream isolation is performed to cut off the fault current supplied by the substation to the fault point.

[0146] Before performing each boundary switch operation, the current open / closed status, remote control capability, communication status, interlocking status, and related protection reset status of the switch can be confirmed. If the current operation is successful, the next operation is executed; if no successful feedback is received within a preset time or failure information such as refusal to operate or communication abnormality is received, subsequent steps are paused, and the failed device, failure location, and failure reason are provided to step S5 for secondary scheme generation.

[0147] After the isolation operation is completed, the voltage and frequency of each distributed power source's grid connection point within the isolation area can be collected to reconfirm the off-grid status. For example, if the effective value of any phase voltage at the grid connection point is greater than 0.1 times the rated voltage, it can be determined that there is residual voltage; if the frequency exceeds 49.5Hz to 50.5Hz, it can be used as a basis for an abnormal state; the current voltage can also be compared with the voltage before the fault, and if the ratio of the two is greater than 0.15 and the corresponding distributed power source was in a grid-connected state before the fault, it can be used as a basis for judging residual voltage.

[0148] To reduce misjudgments caused by residual voltage on the substation side, the output voltage of the upstream feeder at the isolation boundary can be collected simultaneously for cross-judgment. If a suspected residual voltage of a distributed source is detected, the disconnection command can be resent first; if it still cannot be eliminated, the first-level isolation range can be expanded upstream of the corresponding grid connection point; if it still cannot be eliminated after further isolation, centralized disconnection control can be implemented for the distributed sources within the isolation area, and cases where disconnection cannot be completed will be transferred to manual handling.

[0149] By verifying the status after isolation, the fault isolation result is confirmed not only by whether the boundary switch has completed the tripping, but also by whether the distributed power source in the isolation area has lost its continuous power supply capability.

[0150] In some embodiments, based on the updated load curve, power restoration is performed on the non-faulty power-loss area after fault isolation to obtain the self-healing scheme execution result, including: Step S401: Based on the updated load curve, determine the load to be restored in the non-fault power loss area under the current operating mode.

[0151] In one exemplary embodiment, after fault isolation is completed, non-faulty power loss areas that have lost power due to the fault isolation operation but do not have faults themselves are first identified.

[0152] Non-fault-related power outage areas refer to areas that temporarily lose power supply due to the isolation of faulty areas and the interruption of power supply paths. The lines, load equipment, and power consumption nodes in these areas are not faulty, and power supply can be restored by adjusting the power supply path.

[0153] Since the connection and disconnection of distributed generation sources from the grid will change the actual power flow distribution of the distribution network, the historical load data before the fault occurred cannot be directly used as the basis for recovery. Instead, the updated load curve can be used to determine the actual load demand under the current operating mode.

[0154] Specifically, based on the topology nodes corresponding to the non-faulty power loss areas, load power data for the corresponding time period is obtained from the updated load curve, and the load that needs to be restored in the area is determined in combination with the current operating status of the distributed power source. Specifically, the output provided by the distributed power source connected to the area can offset part of the load demand. Therefore, the actual load to be restored is equal to the total load of the area minus the effective output of the distributed power source that is still in normal grid-connected operation.

[0155] Step S402: Based on the topological connection between the non-faulty power loss area and the available power supply side in the distribution network, search for candidate power supply paths to restore the load to be restored.

[0156] After identifying the load to be restored, candidate power supply paths that can provide power support to the non-faulty power loss area are searched based on the current topological connection between the non-faulty power loss area and the available power supply side in the distribution network.

[0157] The available power supply side may include adjacent feeders, interconnecting power supply lines, backup power supply equipment, and distributed power sources that can participate in power restoration.

[0158] Specifically, the power supply node corresponding to the non-faulty power loss area can be used as the starting point for the search. Based on the current distribution network topology, the search can be conducted along different power supply directions to find lines and switch combinations that can form an effective electrical connection.

[0159] During the search process, it is possible to determine whether a power supply path meets the candidate conditions based on the current connection status of the line, the current open / closed status of the switch, whether the power supply side has the power supply capability, and whether there is a fault area in the path.

[0160] For example, when a feeder terminal area loses power after fault isolation, the status of the tie switch between adjacent feeders can be searched to determine whether a new power supply path can be established by closing the tie switch; when there is available distributed power source downstream, it can also be used as a candidate power supply resource based on the current operating status of the distributed power source.

[0161] After the above search, multiple candidate power supply paths can be obtained, and each candidate power supply path corresponds to a set of lines, switches and power supply node relationships.

[0162] Step S403: Verify the power supply capacity of each candidate power supply path according to the load to be restored, and determine the target power supply path from the candidate power supply paths that meet the preset power supply capacity requirements.

[0163] After obtaining candidate power supply paths, it is necessary to further determine whether each candidate power supply path can meet the power supply requirements of the load to be restored.

[0164] Specifically, power supply capacity verification can be performed for each candidate power supply path. Power supply capacity verification can include power supply capacity verification, line carrying capacity verification, and operational constraint verification.

[0165] Among them, the power supply capacity verification is to determine whether the remaining capacity of the power supply side corresponding to the candidate power supply path can bear the load to be restored.

[0166] For example, if the current remaining capacity of the power supply side corresponding to a candidate path is insufficient to handle the load in a non-faulty power outage area, then the candidate path does not meet the power supply requirements.

[0167] Line carrying capacity verification is to determine whether the lines, transformers and switching equipment in the candidate power supply path can withstand the power flow changes after restoration.

[0168] Operational constraint verification is used to determine whether restoring power will cause line overload, voltage exceeding limits, or affect other areas with normal power supply.

[0169] In one specific implementation, the load to be restored can be determined based on the updated load curve and matched with the power supply capacity of candidate power supply paths. If a candidate power supply path can meet the demand of the load to be restored and also satisfies the distribution network operation constraints, then the candidate power supply path is determined to be an executable path.

[0170] When multiple candidate power supply paths meet the requirements, they can be further compared based on path length, number of operations, power margin, or impact on other areas. The candidate power supply path with the best overall performance can be selected as the target power supply path. Generally, the target power supply path meets the requirements.

[0171] The recovery path that meets the power demand, requires the fewest number of switch operations, has the smallest power outage area, and has the largest power margin is the one that can reduce the amount of control operations and minimize the impact on the user's power supply while ensuring reliable power restoration, thus balancing the economy and reliability of fault recovery.

[0172] The above process avoids selecting a recovery path solely based on topological connectivity, and instead determines the recovery plan based on meeting the actual power supply capacity.

[0173] Step S404: Generate and execute a power restoration operation based on the target power supply path, and obtain the self-healing solution execution result based on the execution status of the power restoration operation.

[0174] After determining the target power supply path, a corresponding power restoration operation sequence is generated based on the lines, switches, and power supply equipment involved in the target power supply path.

[0175] Specifically, the power restoration operation sequence may include closing the control tie switch, adjusting the status of relevant switches, restoring the power supply connection to the target area, and adjusting the operating status of distributed power sources.

[0176] Before performing a power restoration operation, the status of the equipment in the target power supply path can be verified, such as confirming that the relevant switches are remotely controlled, the communication status is normal, and there are no faults in the target path.

[0177] During execution, real-time feedback information for each operation step is obtained. If each operation step is executed successfully and power is restored to the non-faulty power-loss area, the power restoration is considered successful. If there are issues such as switch failure, communication abnormalities, insufficient power supply capacity, or failure to meet operational constraints after restoration, the power restoration is considered a failure, and the corresponding failed device and failure stage information are recorded.

[0178] The execution result of the self-healing scheme is used to characterize the execution status of the current recovery scheme, which may include whether the power supply was successfully restored, whether the power supply failed, the device corresponding to the execution failure, the reason for the execution failure, and the stage at which the execution failure occurred.

[0179] When power restoration fails, the result serves as the basis for adjusting the subsequent secondary self-healing scheme. Based on the stage of the failed device and its topological position relative to the fault location, the power restoration method or fault isolation method is readjusted.

[0180] In some embodiments, based on the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, the fault isolation method or power restoration method is adjusted to generate and execute a secondary self-healing scheme, including: Step S501: Based on the operation process corresponding to the execution failure, determine whether the device corresponding to the execution failure is in the fault isolation stage or the power supply recovery stage, and determine the topology of the device corresponding to the execution failure based on the topology connection relationship between the device corresponding to the execution failure and the fault location.

[0181] Among them, the topology side can be determined based on the real-time topology connection relationship between the failed device and the fault location.

[0182] For example, the direction from the substation or main power supply side along the power supply topology to the fault location can be used to determine the upstream side of the fault; the direction extending from the fault location to the end of the line or the load side can be used to determine the downstream side of the fault.

[0183] By combining the self-healing phase with topology differentiation, at least four types of failure scenarios can be formed: upstream isolation failure, downstream isolation failure, upstream recovery failure, and downstream recovery failure. Different failure scenarios correspond to different adjustment targets, so that the secondary self-healing scheme no longer adopts a uniform fixed processing rule.

[0184] Step S502: When the device corresponding to the execution failure is in the fault isolation stage, search for alternative isolation locations along the corresponding direction according to the topology, and adjust the fault isolation method in combination with the distributed power status in the adjusted isolation area.

[0185] When an execution failure occurs during the fault isolation phase and the failed device is located upstream of the fault location, an operable alternative disconnect switch can be searched along the upstream direction. The nearest available alternative disconnect switch is taken as the new upstream isolation location, and the original failed switch and the area between it and the fault location are included in the new isolation range.

[0186] When an execution failure occurs during the fault isolation phase and the failed device is downstream of the fault location, a search for a new operable disconnect switch can continue downstream, while simultaneously re-checking the status of distributed power sources in the expanded isolation area. Before performing new downstream isolation operations, distributed power sources within the expanded area that can be independently disconnected from the grid can be disconnected first, thereby preventing distributed power sources from continuously supplying power to the isolation area after the downstream isolation is expanded.

[0187] Through the above differentiated processing, upstream isolation failure mainly involves replacing the fault current cutoff path on the main power supply side, while downstream isolation failure further considers the impact of distributed power sources potentially continuing to generate reverse feed-in.

[0188] Step S503: When the device corresponding to the execution failure is in the power restoration phase, determine the corresponding non-fault power failure area according to the topology, and adjust the power restoration method according to the load to be restored and the available power resources in the non-fault power failure area.

[0189] When the execution fails during the power restoration phase, it indicates that the faulty area has been isolated, but some non-faulty power loss areas have failed to have their power restored according to the original power restoration plan.

[0190] Specifically, the affected non-faulty power loss area is determined based on the topological side of the failed device relative to the fault location.

[0191] For example, when the failed device is located upstream of the fault location, the recovery path on the main power supply side usually fails. In this case, the focus should be on adjusting the power supply recovery method for the non-faulty area upstream. When the failed device is located downstream of the fault location, the corresponding load-side recovery path usually fails. In this case, it is necessary to re-determine the recovery method based on the load demand of the downstream area and the availability of distributed power sources.

[0192] Furthermore, alternative power supply paths are searched again based on the loads to be restored and available power resources corresponding to the non-faulty power loss areas.

[0193] The load to be restored can be determined based on the updated load curve, including the actual power demand of each load node under the current operating mode.

[0194] Available power supply resources may include the power transfer capacity of adjacent feeders, the power supply capacity of tie lines, backup power supply equipment, and distributed power sources that can participate in power restoration.

[0195] For example, when the upstream recovery path fails, other connection lines or backup power supply paths can be searched again; when the downstream recovery path fails, it can be further determined whether the downstream distributed power source currently has the ability to support the local load, and the recovery plan can be adjusted according to the status of the distributed power source.

[0196] The above method allows for dynamic changes to the power restoration target and restoration path based on the location of the failure, avoiding secondary failures caused by using a fixed restoration path.

[0197] In one specific embodiment, the current active power of each load node can be determined based on the updated load curve, and a corrected load to be restored can be formed by combining the load change trend before and after the fault. Restoration weights are set according to load level; for example, a weight of 1.0 for level 1 loads, 0.6 for level 2 loads, and 0.3 for level 3 loads. The load restoration priority score can then be expressed as:

[0198] in, This indicates the weight corresponding to the load level. This indicates the load power after correction based on the current load condition. This indicates the recovery priority score for the corresponding load.

[0199] In this process, each load node is sorted from highest to lowest according to its load recovery priority score, and the first k preset load nodes are selected as loads to be restored.

[0200] Furthermore, for each load to be restored, a topology search can be used to search for available tie switches, backup transformers, or adjacent power supply paths, and capacity checks can be performed on the candidate paths.

[0201] For candidate power supply paths that pass capacity verification, comparisons can also be made based on the number of operations, power supply capacity margin, and path electrical distance. Capacity margin can be expressed as:

[0202] in, Indicates the available power supply capacity of the candidate path. This indicates the load demand to be restored.

[0203] The comprehensive score of candidate paths can be expressed as:

[0204] in, This represents the score based on the number of operations. This indicates the score based on capacity margin. This represents the score based on the electrical distance along the path. The fewer operations required, the higher the score based on the number of operations. Specifically, this can be achieved by selecting the historical operation counts of each candidate path within a preset historical window length, normalizing the historical operation counts of each candidate path, and then taking the reciprocal of the normalized operation counts as... It should be noted that the historical operation count for each candidate path cannot be zero; that is, a historical window with a non-empty historical operation count must be selected. This prioritizes recovery schemes with simpler operation steps, reducing the probability of secondary anomalies during the operation.

[0205] In the scoring based on capacity margin, a larger margin results in a higher score. This ensures that the restored power supply path has sufficient safety margin for operation and reduces the risk of overload. Specifically, the capacity margin of each candidate power supply path is normalized, and the normalized capacity margin is used as the score for capacity margin calculation. .

[0206] In the scoring based on path electrical distance, a shorter electrical distance results in a higher score, thereby reducing line losses and improving power supply efficiency. Specifically, the total resistance value of each candidate path is used as the basis for calculating the electrical distance. After normalizing the total resistance of each candidate path, the reciprocal of the normalized resistance value is taken as the score for path electrical distance. Prioritize power supply paths with shorter electrical distances.

[0207] After calculating the comprehensive score of all candidate paths, the candidate path with the highest comprehensive score is selected as the target power supply path. Through the above dynamic adjustment strategy, differentiated adjustment methods can be adapted to different failure scenarios that occur during the execution of a self-healing scheme, avoiding the inability to restore power supply for a long time after a fault recovery failure due to fixed recovery logic, and further improving the reliability of active distribution network fault self-healing.

[0208] Step S504: Generate a secondary self-healing scheme based on the adjusted fault isolation method or power supply restoration method, and execute the secondary self-healing scheme.

[0209] After generating the secondary self-healing solution, the execution status of each operation step can be monitored.

[0210] If the process fails again, the device that failed this time can be compared with the device that failed previously. If the failure is still caused by the same device, a new isolation location or a new power supply path can be searched in the corresponding direction based on the previous adjustment results. If the failed device changes, the self-healing stage and topology side corresponding to the new failed device can be redefined, and the corresponding adjustment method can be rematched.

[0211] In one specific implementation, the secondary scheme can undergo a limited number of iterations, for example, a maximum of 3 times. If self-healing cannot be completed after reaching the preset number of iterations, the automatic expansion will stop, and process information such as fault events, failed devices, executed operations, and reasons for failure will be sent to the scheduler for manual processing.

[0212] Each solution generation and execution process can be associated and recorded according to the fault event ID. The record content includes at least the time of failure, the failed device, the failure stage, the topology, the adjustment method used, the corresponding operation sequence, the execution result of each operation step, and the execution time of the solution, thereby supporting the subsequent tracing of the cause of self-healing failure and the effect of strategy execution.

[0213] Based on the same inventive concept, this application also provides an active distribution network self-healing strategy adaptive adjustment system for implementing the above-mentioned active distribution network self-healing strategy adaptive adjustment method.

[0214] The solution provided by this system is similar to the solution described in the above method. Therefore, the specific limitations of one or more embodiments of the self-healing strategy adaptive adjustment system for active distribution networks provided below can be found in the limitations of the self-healing strategy adaptive adjustment method for active distribution networks described above, and will not be repeated here.

[0215] like Figure 3 As shown in the embodiments of this application, a self-healing strategy adaptive adjustment system for an active power distribution network is also provided. This system includes: The information acquisition module 100 is used to acquire the operating status of distributed power sources and the operation information of the distribution network in the active distribution network; The setting update module 200 is used to update the protection settings and load curves that are adapted to the current operating mode based on the changed operating status and distribution network operating information when the operating status of the distributed power source changes. The fault isolation module 300 is used to obtain fault detection information generated by the protection device with updated protection settings when a fault occurs in the active distribution network, determine the fault location based on the fault detection information, determine the fault isolation boundary based on the fault location and the distribution of distributed power sources, and perform fault isolation based on the fault isolation boundary. The self-healing scheme execution module 400 is used to restore power supply to the non-faulty power loss area after fault isolation based on the updated load curve, and obtain the self-healing scheme execution result. The secondary self-healing scheme execution module 500 is used to generate and execute a secondary self-healing scheme when the execution result of the self-healing scheme indicates that there is an execution failure, based on the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, by adjusting the fault isolation method or power supply restoration method.

[0216] In some embodiments, the setpoint update module 200 is used for: Based on the changed operating status of each distributed power source, combined with the access status of each distributed power source and the current topology connection relationship of the distribution network, determine the current operating mode of the active distribution network and the protection devices affected by the change in operating status. Based on the current operating mode, determine the protection setting value corresponding to the protection device from the pre-established correspondence between different operating modes and protection settings, and update the protection setting value to the corresponding protection device; Based on the power distribution network operation information, determine the power direction of each preset monitoring point before and after the change in operating status, and adjust the corresponding power data according to the change in power direction; The load curve is updated based on the adjusted power data and the corresponding changes in operating status.

[0217] In some embodiments, the fault isolation module 300 is used for: Obtain protection action information generated by protection devices operating with updated protection settings, and obtain power distribution terminal fault information within the fault period corresponding to the protection action information; Based on the equipment location and fault response direction corresponding to the protection action information and the power distribution terminal fault information, the protection action information and the power distribution terminal fault information are correlated to obtain fault detection information; Based on the correspondence between fault detection information and the current topology connection relationship of the distribution network, candidate fault sections that match each fault response are determined; The target fault section is determined based on the fault response status of each candidate fault section, and the target fault section is identified as the fault location.

[0218] In some embodiments, the fault isolation module 300 is used for: Search along the upstream and downstream directions of the fault location according to the topological connection relationship of the active distribution network to determine the initial isolation boundary used to limit the fault section; Based on the distribution of distributed power sources within the initial isolation boundary area and the off-grid capability of the corresponding distributed power sources, the initial isolation boundary is adjusted to obtain the fault isolation boundary. The isolation operation is performed by the boundary switch corresponding to the fault isolation boundary control to isolate the fault in the area corresponding to the fault location.

[0219] In some embodiments, the fault isolation module 300 is used for: Identify the distributed power sources within the initial isolation boundary area and determine whether each distributed power source has independent off-grid capability. For distributed power sources with independent off-grid capability, control the corresponding distributed power source to perform off-grid execution, and determine whether the corresponding distributed power source can remain in the current isolation area based on the off-grid execution result; For distributed power sources that do not have independent off-grid capability or have failed to be off-grid, search outwards along the topology connection relationship of the corresponding distributed power source branch to find switches that can perform isolation operations, and adjust the current isolation boundary according to the found switches so that the power supply path of the corresponding distributed power source is isolated from the fault area. The off-grid status of distributed power sources in the isolation area is redefined based on the adjusted isolation area, and the current isolation boundary is adjusted based on the off-grid status until the adjusted isolation area meets the preset isolation conditions. The corresponding current isolation boundary is then determined as the fault isolation boundary.

[0220] In some embodiments, the self-healing scheme execution module 400 is configured to: Based on the updated load curve, determine the load to be restored in the non-fault power loss area under the current operating mode; Based on the topological connection between the non-faulty power loss area and the available power supply side in the distribution network, search for candidate power supply paths to restore the load to be restored; The power supply capacity of each candidate power supply path is checked based on the load to be restored, and the target power supply path is determined from the candidate power supply paths that meet the preset power supply capacity requirements. The system generates and executes power restoration operations based on the target power supply path, and obtains the self-healing solution execution result based on the execution status of the power restoration operations.

[0221] In some embodiments, the secondary self-healing scheme execution module 500 is used for: Based on the operation process corresponding to the execution failure, determine whether the device corresponding to the execution failure is in the fault isolation stage or the power restoration stage, and determine the topology of the device corresponding to the execution failure based on the topological connection relationship between the device corresponding to the execution failure and the fault location. When the device corresponding to the execution failure is in the fault isolation stage, search for alternative isolation locations along the corresponding direction according to the topology, and adjust the fault isolation method in combination with the distributed power status in the adjusted isolation area; When the device corresponding to the execution failure is in the power restoration phase, the corresponding non-fault power failure area is determined according to the topology, and the power restoration method is adjusted according to the load to be restored and the available power resources in the non-fault power failure area. A secondary self-healing scheme is generated based on the adjusted fault isolation method or power restoration method, and then the secondary self-healing scheme is executed.

[0222] like Figure 4 As shown, this application provides an electronic device. The electronic device 10 includes a memory 20 and a processor 30. The memory 20 stores a computer program. When the computer program is executed by the processor 30, the processor 30 performs the steps of the self-healing strategy adaptive adjustment method for active power distribution networks as described in the above embodiment.

[0223] This application provides a computer-readable storage medium storing a computer program thereon, which, when executed, implements the steps of the self-healing strategy adaptive adjustment method for active power distribution networks as described in the above embodiments.

[0224] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, electronic devices, and computer storage media described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0225] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0226] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0227] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0228] In the embodiments provided by this invention, it should be understood that the disclosed systems, electronic devices, computer storage media, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units through some interfaces, and may be electrical, mechanical, or other forms.

[0229] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0230] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0231] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of the present invention through a computer device (which may be a personal computer, a server, or a network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0232] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A self-healing strategy adaptive adjustment method for an active distribution network, characterized in that, The method includes: To obtain the operating status of distributed generation sources and distribution network operation information in active distribution networks; When the operating status of the distributed power source changes, the protection settings and load curves adapted to the current operating mode are updated according to the changed operating status and the distribution network operating information. When a fault occurs in the active distribution network, the fault detection information generated by the protection device using the updated protection settings is obtained, the fault location is determined based on the fault detection information, and the fault isolation boundary is determined based on the fault location and the distribution of the distributed power sources, and fault isolation is performed based on the fault isolation boundary. Based on the updated load curve, power supply is restored to the non-faulty power loss area after fault isolation, and the self-healing scheme execution result is obtained. When the execution result of the self-healing scheme indicates that there is an execution failure, the fault isolation method or power supply restoration method is adjusted according to the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, and a secondary self-healing scheme is generated and executed.

2. The self-healing strategy adaptive adjustment method for active distribution networks according to claim 1, characterized in that, The step of updating the protection settings and load curves to adapt to the current operating mode based on the changed operating status and the distribution network operating information includes: Based on the changed operating status of each distributed power source, combined with the access status of each distributed power source and the current topology connection relationship of the distribution network, the current operating mode of the active distribution network and the protection devices affected by the change in operating status are determined. Based on the current operating mode, the protection setting value corresponding to the protection device is determined from the pre-established correspondence between different operating modes and protection settings, and the protection setting value is updated to the corresponding protection device; The power direction of each preset monitoring point before and after the change in the operating state is determined based on the power distribution network operation information, and the corresponding power data is adjusted according to the change in the power direction. The load curve is updated based on the adjusted power data and its corresponding changes in operating status.

3. The self-healing strategy adaptive adjustment method for active distribution networks according to claim 1, characterized in that, The step of acquiring fault detection information generated by the protection device using the updated protection settings, and determining the fault location based on the fault detection information, includes: Obtain protection action information generated by the protection device operating with the updated protection settings, and obtain power distribution terminal fault information within the fault period corresponding to the protection action information; Based on the equipment location and fault response direction corresponding to the protection action information and the power distribution terminal fault information, the protection action information and the power distribution terminal fault information are associated to obtain the fault detection information; Based on the correspondence between the fault detection information and the current topology connection relationship of the distribution network, candidate fault sections that match each fault response are determined; The target fault segment is determined based on the fault response status corresponding to each of the candidate fault segments, and the target fault segment is determined as the fault location.

4. The self-healing strategy adaptive adjustment method for active distribution networks according to claim 1 or 3, characterized in that, The step of determining the fault isolation boundary based on the fault location and the distribution of the distributed power sources, and performing fault isolation based on the fault isolation boundary, includes: Searching along the upstream and downstream directions of the fault location according to the topological connection relationship of the active distribution network, respectively, to determine the initial isolation boundary used to define the fault section; Based on the distribution of distributed power sources within the initial isolation boundary area and the off-grid capability of the corresponding distributed power sources, the initial isolation boundary is adjusted to obtain the fault isolation boundary. The isolation operation is performed according to the boundary switch corresponding to the fault isolation boundary control to isolate the fault in the area corresponding to the fault location.

5. The self-healing strategy adaptive adjustment method for active distribution networks according to claim 4, characterized in that, The step of adjusting the initial isolation boundary based on the distribution of distributed power sources within the initial isolation boundary area and the off-grid capability of the corresponding distributed power sources to obtain the fault isolation boundary includes: Identify the distributed power sources within the initial isolation boundary area, and determine whether each of the distributed power sources has independent off-grid capability; For distributed power sources with independent off-grid capability, control the corresponding distributed power source to perform off-grid execution, and determine whether the corresponding distributed power source can remain in the current isolation area based on the off-grid execution result; For distributed power sources that do not have independent off-grid capability or have failed to be off-grid, search outwards along the topology connection relationship of the corresponding distributed power source branch to find switches that can perform isolation operations, and adjust the current isolation boundary according to the found switches so that the power supply path of the corresponding distributed power source is isolated from the fault area. The off-grid status of the distributed power sources in the isolation area is re-determined based on the adjusted isolation area, and the current isolation boundary is adjusted based on the off-grid status until the adjusted isolation area meets the preset isolation conditions. The corresponding current isolation boundary is then determined as the fault isolation boundary.

6. The self-healing strategy adaptive adjustment method for active distribution networks according to claim 1, characterized in that, Based on the updated load curve, power restoration is performed on the non-faulty power-loss areas after fault isolation to obtain the self-healing scheme execution results, including: Based on the updated load curve, determine the load to be restored in the non-fault power loss area under the current operating mode; Based on the topological connection between the non-faulty power loss area and the available power supply side in the distribution network, search for candidate power supply paths to restore the load to be restored; The power supply capacity of each candidate power supply path is checked according to the load to be restored, and the target power supply path is determined from the candidate power supply paths that meet the preset power supply capacity requirements. A power restoration operation is generated and executed based on the target power supply path, and the execution result of the self-healing scheme is obtained based on the execution status of the power restoration operation.

7. The self-healing strategy adaptive adjustment method for active distribution networks according to claim 1, characterized in that, The step of adjusting the fault isolation method or power restoration method based on the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, and generating and executing a secondary self-healing scheme, includes: Based on the operation process corresponding to the execution failure, it is determined whether the device corresponding to the execution failure is in the fault isolation stage or the power supply recovery stage, and based on the topological connection relationship between the device corresponding to the execution failure and the fault location, the topological side of the device corresponding to the execution failure is determined. When the device corresponding to the execution failure is in the fault isolation stage, an alternative isolation location is searched along the corresponding direction according to the topology, and the fault isolation method is adjusted in combination with the distributed power status in the adjusted isolation area. When the device corresponding to the execution failure is in the power restoration phase, the corresponding non-fault power failure area is determined according to the topology, and the power restoration method is adjusted according to the load to be restored and the available power resources in the non-fault power failure area. The secondary self-healing scheme is generated based on the adjusted fault isolation method or power supply restoration method, and the secondary self-healing scheme is executed.

8. A self-healing adaptive adjustment system for an active power distribution network, characterized in that, The system includes: The information acquisition module is used to acquire the operating status of distributed generation in the active distribution network and the operation information of the distribution network. The setting update module is used to update the protection settings and load curves that are adapted to the current operating mode based on the changed operating state and the distribution network operating information when the operating state of the distributed power source changes. The fault isolation module is used to acquire fault detection information generated by the protection device using the updated protection settings when a fault occurs in the active distribution network, determine the fault location based on the fault detection information, determine the fault isolation boundary based on the fault location and the distribution of the distributed power sources, and perform fault isolation based on the fault isolation boundary. The self-healing scheme execution module is used to restore power supply to the non-faulty power loss area after fault isolation based on the updated load curve, and obtain the self-healing scheme execution result. The secondary self-healing scheme execution module is used to generate and execute a secondary self-healing scheme when the execution result of the self-healing scheme indicates that there is an execution failure, based on the self-healing stage of the device corresponding to the execution failure and the topology relative to the fault location, by adjusting the fault isolation method or power supply restoration method.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the processor performs the steps of the self-healing strategy adaptive adjustment method for active power distribution networks as described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the steps of the self-healing strategy adaptive adjustment method for active distribution networks as described in any one of claims 1-7.

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