A power distribution network dynamic reconstruction and optimal scheduling system for a new power system

Abstract

The application relates to the technical field of power distribution network operation control, and discloses a power distribution network dynamic reconstruction and optimization scheduling system for a new power system, which comprises a data access module, an envelope construction module, a topology generation module, a power flow projection module, a protection checking module, a matching module, a scheduling decision module, a time sequence control module and a feedback updating module. The system generates a node flexible operation envelope according to topology, measurement, adjustable resources, historical response and protection setting value data, and screens a flexible executable topology according to the node flexible operation envelope; when power flow exceeds a limit, resource correction and / or switch fine adjustment are carried out to obtain a power flow executable topology; then protection checking and setting value group matching are carried out to determine a target reconstruction topology and execute the target reconstruction topology according to a safe time sequence. The system can improve the physical executability and protection safety of a power distribution network reconstruction scheme.

Description

Technical Field

[0001] This invention relates to the field of power distribution network operation control technology, and in particular to a power distribution network dynamic reconfiguration and optimization scheduling system for new power systems. Background Technology

[0002] With the advancement of new power system construction, the proportion of distributed power sources, energy storage devices, electric vehicle charging facilities, flexible loads, and controllable reactive power equipment connected to the distribution network is continuously increasing. These devices have changed the relatively fixed operating characteristics of the power source and load sides in the traditional distribution network, causing the distribution network to gradually exhibit characteristics such as bidirectional power flow, frequent changes in operating status, enhanced coupling between power sources, grids, loads, and storage, and dynamic changes in local operating boundaries.

[0003] Under the aforementioned operating environment, the operation and control of the distribution network no longer involves only adjusting switch states; it also requires comprehensive consideration of factors such as node power changes, voltage levels, line current carrying capacity, transformer capacity, the impact of distributed power source integration, and the response of adjustable resources on the user side. There are strong correlations between different types of operational data, and some data exhibit real-time characteristics, volatility, and uncertainty, posing significant challenges to the dynamic reconfiguration and optimized scheduling of the distribution network.

[0004] When the distribution network topology changes, the load transfer path, node injected power, branch power flow distribution, and local voltage levels may change simultaneously. If the resource absorption capacity of the nodes is not fully considered during the reconfiguration process, a situation may arise where the topology meets operational requirements, but the actual power changes are difficult for the corresponding nodes to absorb or support, thus affecting the feasibility of the reconfiguration plan.

[0005] Meanwhile, in scenarios with a high proportion of distributed power sources and flexible load access, the power flow distribution after topology adjustment is more susceptible to the influence of local resource output, load response, and energy storage status. When node voltage, branch current, transformer load rate, or reverse power flow approaches the operating boundary, relying solely on topology adjustment is insufficient to guarantee the stability and security of the reconfiguration results in actual operation.

[0006] Furthermore, changes in the distribution network topology may alter fault current paths and the coordination relationships between protection devices. If the relay protection operating time limits and the coordination requirements between upper and lower level protections are not fully considered during the reconfiguration and dispatching process, the risk of protection maloperation, failure to operate, or over-level tripping may increase, affecting the reliability of distribution network fault isolation and power restoration.

[0007] In actual implementation, there are sequential dependencies among switchover, energy storage regulation, distributed power source regulation, charging load adjustment, flexible load response, and protection-related operations. If various control commands lack unified coordination, problems such as mismatched execution order, insufficient resource response, or deviation from expected operating status can easily occur, thereby reducing the safety, accuracy, and adaptability of dynamic reconfiguration and optimized scheduling of the distribution network.

[0008] Therefore, how to improve the feasibility, security, and coordination of dynamic reconfiguration schemes for distribution networks under new power system scenarios has become a pressing technical problem to be solved in the field of distribution network operation and control. Summary of the Invention

[0009] To address the shortcomings of existing technologies, the present invention aims to provide a dynamic reconfiguration and optimized scheduling system for distribution networks in new power systems, which improves the overall executability of distribution network reconfiguration topology in terms of node flexibility, power flow physical constraints, protection and security coordination, and scheduling execution timing.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system, comprising: The data access module is used to collect topology data, measurement data, adjustable resource operation data, historical response data and protection setting data, and output the operation dataset after verification; The envelope construction module connects to the data access module and is used to generate flexible operational envelopes for each node based on the operational dataset. The topology generation module connects the data access module and the envelope construction module. It is used to generate candidate reconstructed topologies based on the running dataset and to determine the candidate reconstructed topologies whose node prediction power points fall within the corresponding node's flexible running envelope as flexible executable topologies. The power flow projection module connects the topology generation module and the envelope construction module. It is used to perform power flow calculation on the flexible executable topology, and to perform resource correction and / or switch fine-tuning based on the flexible running envelope of the node when the limit is exceeded, and output the power flow executable topology. The protection verification module is connected to the power flow projection module and the data access module. It is used to verify the short-circuit current path and action time of the power flow executable topology based on the protection setting data, and output the protection executable topology or the protection topology to be corrected. The matching module, connected to the protection verification module, is used to match a backup protection setting group for the protection topology to be corrected, and to convert the verified topology into a protection executable topology. The scheduling decision module, which connects the protection verification module and the matching module, is used to determine the target reconstructed topology from the protection executable topology and generate a collaborative scheduling instruction. The timing control module, connected to the scheduling decision module, is used to execute coordinated scheduling instructions in the order of protection setting group preloading, flexible resource pre-adjustment, protection setting group input confirmation, and switch switching. The feedback update module, connected to the timing control module, is used to update the node flexible operation envelope, candidate reconstruction topology screening rules, protection setting group matching rules, and comprehensive scheduling decision weights based on the execution results of the collaborative scheduling instructions.

[0011] Furthermore, the envelope construction module includes: The resource ownership identification unit is used to determine the distribution node to which the distributed power source, energy storage device, charging load and flexible load belong based on the operation dataset, and to uniquely assign the same adjustable resource to the distribution node corresponding to its electrical access point within the same scheduling cycle, thereby obtaining the node resource ownership relationship. Adjustable capacity calculation unit, connected to the resource ownership identification unit, is used to calculate the active power up-adjustment capacity, active power down-adjustment capacity, reactive power up-adjustment capacity and reactive power down-adjustment capacity of each distribution node according to the node resource ownership relationship and the adjustable resource operation data, so as to obtain node adjustable capacity data. The envelope boundary generation unit, connected to the adjustable capacity calculation unit, is used to generate the upper boundary of active power, the lower boundary of active power, the upper boundary of reactive power, the lower boundary of reactive power, and the active and reactive capacity coupling constraints of each distribution node based on the node adjustable capacity data, so as to obtain the flexible operation envelope of the node.

[0012] Furthermore, the envelope construction module also includes: A trusted response correction unit, connected to the envelope boundary generation unit, is used to correct the node flexible operation envelope based on the historical response data and the execution result of the cooperative scheduling instruction. Specifically, when the historical response success rate of the adjustable resource is lower than a preset trust threshold, the available boundary of the corresponding adjustable resource in the flexible operation envelope of the node is reduced. When the adjustable resource continuously meets the preset trusted response conditions, the trusted response weight of the corresponding adjustable resource is increased, and the corrected node flexible operation envelope does not exceed the rated capacity of the corresponding adjustable resource.

[0013] Furthermore, the topology generation module includes: The topology modeling unit is used to build a distribution network topology diagram including distribution nodes, branches and controllable switches based on the running dataset. A switch combination generation unit, connected to the topology modeling unit, is used to generate candidate switch combinations based on the current state of controllable switches in the distribution network topology. The topology constraint judgment unit, connected to the switch combination generation unit, is used to determine the candidate switch combinations that satisfy radial operation constraints, no isolated distribution node constraints, prohibited operation switch constraints, and preset switch action constraints as candidate reconstructed topologies. The node power offset calculation unit, connected to the topology constraint judgment unit, is used to calculate the active power offset and reactive power offset of each distribution node after switching from the current topology to the candidate reconfiguration topology, and to obtain the node predicted power point. The envelope filtering unit, connected to the node power offset calculation unit, is used to determine the candidate reconfigurable topology that falls within the node flexible operation envelope of the corresponding distribution node as the flexible executable topology.

[0014] Furthermore, the current projection module includes: A power flow calculation unit is used to receive the flexible executable topology, perform power flow calculation on the flexible executable topology, and obtain the power flow calculation result; The limit-crossing identification unit, connected to the power flow calculation unit, is used to identify the power flow limit-crossing object and the power flow limit-crossing type based on the power flow calculation result; wherein, the power flow limit-crossing object includes at least one of distribution node, branch, transformer and grid connection point, and the power flow limit-crossing type includes at least one of node voltage limit-crossing, branch current limit-crossing, transformer load rate limit-crossing and reverse power flow limit-crossing. The resource correction unit, connected to the limit identification unit, is used to generate a resource correction amount when the power flow limit is exceeded in the flexible executable topology, using the node's flexible operation envelope as the constraint boundary of the resource correction amount. A switch fine-tuning unit, connected to the resource correction unit, is used to generate a switch fine-tuning scheme that does not destroy the radial operation constraints and does not cause the node prediction power point after switch fine-tuning to exceed the node flexible operation envelope of the corresponding distribution node when the resource correction amount cannot eliminate the power flow over-limit. The projection iteration unit, connected to the resource correction unit, the switch fine-tuning unit, and the power flow calculation unit, is used to adjust the corresponding adjustable resources according to the resource correction amount and / or adjust the corresponding controllable switches according to the switch fine-tuning scheme, and then re-trigger power flow calculation until the node voltage, branch current, transformer load rate, and reverse power flow of the topology after resource correction and / or switch fine-tuning meet the corresponding preset safety thresholds, and then determine it as the power flow executable topology.

[0015] Furthermore, the resource correction unit includes: The over-limit type assignment subunit is used to assign each power flow over-limit object to a voltage over-limit category, voltage over-limit category, overload category, or reverse power flow category according to a preset priority. The same power flow over-limit object is assigned to only one category in the same iteration round. The overload category includes branch current over-limit category and / or transformer load rate over-limit category. The voltage limit exceedance correction subunit is connected to the limit exceedance type dispatch subunit and is used to generate at least one resource correction amount among distributed power source reactive power absorption, energy storage charging and distributed power source limited generation when the power flow limit exceedance object belongs to the voltage limit exceedance category. The voltage lower limit correction subunit is connected to the over-limit type dispatch subunit and is used to generate at least one resource correction amount among energy storage discharge, distributed power source reactive power support and charging load derating when the power flow over-limit object belongs to the voltage lower limit category. The overload correction subunit, connected to the over-limit type dispatch subunit, is used to generate at least one resource correction amount among charging load adjustment, flexible load response and energy storage discharge when the power flow over-limit object belongs to the overload category. The reverse power flow correction subunit, connected to the over-limit type dispatch subunit, is used to generate at least one resource correction amount among energy storage charging, charging load increasing acceptance power, flexible load response, and distributed power generation limitation when the power flow over-limit object belongs to the reverse power flow category.

[0016] Furthermore, the protection verification module includes: The fault scenario generation unit is used to generate preset fault scenarios based on the power flow executable topology. A short-circuit current calculation unit, connected to the fault scenario generation unit, is used to calculate the short-circuit current under each preset fault scenario and obtain short-circuit current data. The fault path identification unit is connected to the short-circuit current calculation unit and is used to identify the protection devices through which the short-circuit current flows and the relationship between the upper and lower level protections based on the short-circuit current data and the protection setting data, so as to obtain the fault current path data. An action time limit calculation unit is connected to the fault path identification unit and is used to calculate the action time limit of each protection device based on the fault current path data and the protection setting data. The protection selectivity judgment unit is connected to the action time limit calculation unit. It is used to determine whether the power flow executable topology meets the protection selectivity requirements based on the action time limits of the upper and lower level protection devices and the preset coordination time threshold. When the protection selectivity requirements are met, the protection executable topology is output. When the protection selectivity requirements are not met, the protection topology to be corrected is output and the corresponding mismatch protection device is marked.

[0017] Furthermore, the matching module includes: The setting group retrieval unit is used to retrieve a spare protection setting group from the protection setting data according to the mismatch protection device corresponding to the protection topology to be corrected. The operating current adaptation unit, connected to the setting group retrieval unit, is used to filter candidate protection setting groups from the standby protection setting group based on the maximum load current determined by the operating dataset under the protection topology to be corrected, and the minimum short-circuit current determined by the short-circuit current data; wherein the operating current setting of the candidate protection setting group is greater than the maximum load current and less than the minimum short-circuit current. An operating time limit adaptation unit, connected to the operating current adaptation unit, is used to calculate the operating time limits of the upper and lower level protection devices based on the candidate protection setting groups, and to screen candidate protection setting groups that meet the protection selectivity requirements. The protection verification unit is connected to the action time limit adaptation unit. It is used to re-verify the short-circuit current path and action time limit of each of the screened candidate protection setting groups, and to determine the candidate protection setting groups that pass the verification as usable protection setting groups. The matching output unit is connected to the protection verification unit and is used to determine the target protection setting group from the available protection setting groups according to the preset value group selection rules, convert the protection topology to be corrected into the protection executable topology, and output the protection executable topology and the protection setting group switching instruction corresponding to the target protection setting group.

[0018] Furthermore, the timing control module includes: The setting preloading unit is used to preload the target protection setting group to the corresponding protection device according to the coordinated scheduling instruction before the flexible resource pre-adjustment. The target protection setting group is the protection setting group corresponding to the protection setting group switching instruction in the coordinated scheduling instruction, or the current protection setting group of the corresponding protection device. The flexible resource pre-adjustment unit, connected to the setpoint pre-loading unit, is used to perform at least one of the following flexible resource pre-adjustments before switching: energy storage charging and discharging, distributed power reactive power regulation, charging load adjustment, and flexible load response. A setpoint input confirmation unit, connected to the flexible resource pre-adjustment unit, is used to input and confirm the target protection setpoint group after the flexible resource pre-adjustment reaches the preset response condition and before the switch is switched, and generate a setpoint input confirmation result; wherein, the preset response condition includes the actual response amount of the flexible resource reaching the preset ratio threshold corresponding to the target response amount. A switch switching execution unit is connected to the setpoint input confirmation unit and is used to perform switch switching when the setpoint input confirmation result is successful, so as to form the target reconstructed topology; When the confirmation result of the set value input is a failure, the switch switching execution unit shall prohibit the execution of switch switching that would change the fault current path.

[0019] Furthermore, the feedback update module includes: The execution result acquisition unit is used to acquire protection setting group switching results, flexible resource response results, switch switching results, and power flow status after reconfiguration. A response deviation calculation unit, connected to the execution result acquisition unit, is used to calculate the response deviation based on the target response amount corresponding to the collaborative scheduling instruction and the actual response amount corresponding to the flexible resource response result. An envelope update unit, connected to the response deviation calculation unit, is used to update the node's flexible operation envelope based on the response deviation. A topology filtering and updating unit, connected to the execution result acquisition unit, is used to update the candidate reconstruction topology filtering rules according to the switch switching result and the power flow state after reconstruction. A setting value matching and updating unit, connected to the execution result acquisition unit, is used to update the protection setting value group matching rule according to the protection setting value group switching result; The scheduling weight update unit is connected to the response deviation calculation unit and the execution result acquisition unit, respectively, and is used to update the comprehensive scheduling decision weight according to the response deviation and the reconstructed power flow state.

[0020] The beneficial effects of this invention are: First, this invention characterizes the adjustable resource acceptance capacity of each distribution node through the flexible operation envelope of the node, and uses it as a preliminary screening condition for candidate topology reconfiguration. This can reduce reconfiguration schemes where node-side resources cannot accept power transfer, and improve the engineering feasibility of topology reconfiguration.

[0021] Second, when there is a power flow limit violation in the flexible executable topology, the present invention performs resource correction and / or switch fine-tuning based on the node flexible operation envelope, and corrects the candidate topology into a power flow executable topology, which is beneficial to improving the utilization rate of the candidate topology and the safety of distribution network operation.

[0022] Third, this invention verifies the short-circuit current path and operating time of the power flow executable topology, and matches the backup protection setting group when the protection does not meet the requirements. This can reduce the number of reconfiguration schemes that are feasible for power flow but not feasible for protection, and improve the reliability of protection coordination after reconfiguration.

[0023] Fourth, the present invention executes the coordinated scheduling instructions in the order of protection setting group preloading, flexible resource pre-adjustment, protection setting group input confirmation and switch switching, which can reduce the risk of protection mismatch and power flow exceeding limits during topology switching.

[0024] Fifth, this invention updates the node flexible operation envelope, candidate reconstruction topology screening rules, protection setpoint group matching rules, and comprehensive scheduling decision weights based on the execution results of the collaborative scheduling instructions, so that the scheduling strategy can adapt to changes in on-site resource response capabilities and operating status. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the distribution network dynamic reconfiguration and optimization dispatch system for a new type of power system in this invention; Figure 2 This is a schematic diagram of the resource correction unit in this invention.

[0026] Figure reference numerals: 1. Data access module; 2. Envelope construction module; 21. Resource ownership identification unit; 22. Adjustable capability calculation unit; 23. Envelope boundary generation unit; 24. Reliable response correction unit; 3. Topology generation module; 31. Topology graph modeling unit; 32. Switch combination generation unit; 33. Topology constraint judgment unit; 34. Node power offset calculation unit; 35. Envelope filtering unit; 4. Power flow projection module; 41. Power flow calculation unit; 42. Limit exceedance identification unit; 43. Resource correction unit; 431. Limit exceedance type assignment subunit; 432. Voltage upper limit correction subunit; 433. Voltage lower limit correction subunit; 434. Overload correction subunit; 435. Reverse power flow correction subunit; 44. Switch fine-tuning unit; 45. Projection iteration unit; 5. Protection Verification Module; 51. Fault Scenario Generation Unit; 52. Short-Circuit Current Calculation Unit; 53. Fault Path Identification Unit; 54. Action Time Calculation Unit; 55. Protection Selectivity Judgment Unit; 6. Matching Module; 61. Setting Group Retrieval Unit; 62. Action Current Adaptation Unit; 63. Action Time Calculation Unit; 64. Protection Verification Unit; 65. Matching Output Unit; 7. Scheduling Decision Module; 8. Timing Control Module; 81. Setting Preloading Unit; 82. Flexible Resource Pre-adjustment Unit; 83. Setting Input Confirmation Unit; 84. Switch Switching Execution Unit; 9. Feedback Update Module; 91. Execution Result Acquisition Unit; 92. Response Deviation Calculation Unit; 93. Envelope Update Unit; 94. Topology Filtering Update Unit; 95. Setting Matching Update Unit; 96. Scheduling Weight Update Unit. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0028] Example 1, as Figure 1As shown, this embodiment provides a dynamic reconfiguration and optimized dispatching system for distribution networks in a new type of power system, applied to an urban distribution network with a high proportion of distributed photovoltaic (PV) and energy storage. This urban distribution network includes two 10kV feeders, multiple sectionalizing switches, one tie switch, several distribution transformers, distributed PV access points, energy storage devices, commercial charging stations, and flexible air conditioning loads. During midday, the PV output at the feeder ends is high, and local distribution nodes face the risk of exceeding the node voltage limit and increased reverse power flow.

[0029] The distribution network dynamic reconfiguration and optimization scheduling system in this embodiment includes a data access module 1, an envelope construction module 2, a topology generation module 3, a power flow projection module 4, a protection verification module 5, a matching module 6, a scheduling decision module 7, a timing control module 8, and a feedback update module 9.

[0030] Data access module 1 is used to collect topology data, measurement data, adjustable resource operation data, historical response data, and protection setting data, and outputs an operation dataset after verification. Topology data includes the connection relationships between feeders, buses, distribution transformers, sectionalizing switches, tie switches, circuit breakers, distributed photovoltaic access points, energy storage access points, charging station access points, and air conditioning flexible load access points. Measurement data includes switch status, node voltage, branch current, active power, reactive power, transformer load rate, and reverse power flow. Adjustable resource operation data includes real-time output of distributed photovoltaic power, predicted output of photovoltaic power, remaining reactive capacity of photovoltaic inverters, energy storage state of charge, rechargeable power of energy storage, rechargeable power of energy storage, current charging power of charging stations, power that can be increased for charging loads, power that can be derated for charging loads, power that can be reduced for air conditioning flexible loads, and response time. Historical response data includes the actual response volume, response time, and response success rate of energy storage, charging loads, and air conditioning flexible loads in historical scheduling. The protection setting data includes the protection device number, the current protection setting group, the standby protection setting group, the operating current setting, the operating time setting, and the coordination relationship between upper and lower level protection.

[0031] Envelope construction module 2 connects to data access module 1 and is used to generate flexible operation envelopes for each node based on the operational dataset. The node flexible operation envelope characterizes the range of active power variation, reactive power variation, and active / reactive capacity coupling that a distribution node can handle within the current scheduling cycle. This envelope is jointly determined by the remaining reactive capacity of the distributed photovoltaic inverter, the charge / discharge capacity of energy storage, the adjustable charging load capacity, the responsiveness of the air conditioning flexible load, and the reliability of historical responses.

[0032] The topology generation module 3 connects the data access module 1 and the envelope construction module 2. It is used to generate candidate reconstructed topologies based on the running dataset and to determine the candidate reconstructed topologies whose node predicted power points fall within the corresponding node's flexible running envelope as flexible executable topologies. This mechanism uses the adjustable resource capabilities of nodes as a prerequisite for topology generation, rather than performing simple scheduling compensation after topology generation. This avoids the formation of reconstructed schemes where the topology is switchable but the node resources are not available.

[0033] The power flow projection module 4 connects the topology generation module 3 and the envelope construction module 2. It is used to perform power flow calculations on the flexible executable topology and, when limits are exceeded, to perform resource correction and / or switch fine-tuning based on the node flexible operation envelope, outputting a power flow executable topology. The power flow projection module 4 calls different flexible resources for correction according to different limit exceedance types, such as node voltage exceeding the upper limit, node voltage exceeding the lower limit, branch current exceeding the limit, transformer load rate exceeding the limit, and reverse power flow exceeding the limit.

[0034] The protection verification module 5 connects to the power flow projection module 4 and the data access module 1. It is used to verify the short-circuit current path and operating time of the executable power flow topology based on the protection setting data, and output the executable protection topology or the protection topology to be corrected. The protection verification module 5 uses relay protection selectivity as a mandatory verification condition before reconfiguration execution to avoid forming a reconfiguration scheme that is feasible in terms of power flow but not in terms of protection execution.

[0035] Matching module 6 connects to protection verification module 5 and is used to match backup protection setting groups for the protection topology to be modified, and to convert the verified topology into a protection executable topology. Matching module 6 selects protection setting groups based on the relationship between maximum load current, minimum short-circuit current, operating current setting, and operating time, so that the protection topology to be modified can continue to participate in dispatching decisions after meeting the protection selectivity requirements.

[0036] The scheduling decision module 7 connects to the protection verification module 5 and the matching module 6. It is used to determine the target reconfigured topology from the protection executable topology and generate collaborative scheduling instructions. The collaborative scheduling instructions include switch switching instructions, energy storage charging and discharging instructions, distributed photovoltaic inverter reactive power regulation instructions, charging load adjustment instructions, air conditioning flexible load response instructions, and protection setting group switching instructions.

[0037] The timing control module 8 is connected to the scheduling decision module 7 and is used to execute coordinated scheduling instructions in the order of protection setting group preloading, flexible resource pre-adjustment, protection setting group activation confirmation, and switch switching. This safe execution timing can avoid the protection mismatch window caused by the switch switching before the protection setting group has been adapted, and can also avoid the risk of power flow exceeding the limit caused by the load being transferred before the flexible resources have responded.

[0038] The feedback update module 9, connected to the timing control module 8, updates the node flexible operation envelope, candidate reconfiguration topology selection rules, protection setting group matching rules, and comprehensive scheduling decision weights based on the execution results of the coordinated scheduling instructions. This feedback mechanism enables the scheduling model to be continuously updated according to the actual response capability on site, avoiding deviations between scheduling results and on-site capabilities caused by long-term use of a static model.

[0039] Hardware selection and supporting environment: In this embodiment, data access module 1 is deployed on the distribution automation master station server. The server uses a processor with no less than 16 cores, 64GB of memory, a 2TB solid-state drive, and dual gigabit Ethernet interfaces. The operating system is a Linux server system, and the database is a combination of time-series database and relational database. Data access module 1 connects to feeder terminals, distribution transformer terminals, protection devices, photovoltaic inverters, energy storage converters, charging station controllers, and building air conditioning controllers via IEC 60870-5-104, Modbus TCP, IEC 61850 MMS, and MQTT communication protocols.

[0040] Envelope construction module 2, topology generation module 3, power flow projection module 4, protection verification module 5, matching module 6, and scheduling decision module 7 are deployed in the same scheduling computing server or edge computing server. Power flow calculation uses a three-phase unbalanced AC power flow calculation program, and protection verification uses a short-circuit current calculation program and a protection action time limit calculation program. Timing control module 8 issues control commands through the distribution automation master station, feeder terminals, and intelligent protection devices. Feedback update module 9 reads execution feedback data from the scheduling master station, protection devices, and adjustable resource controllers.

[0041] The test distribution network includes two 10kV feeders, each with a rated current of 400A. Each feeder contains three sectionalizing switches, and there is one tie switch between the two feeders. The distribution transformer capacity ranges from 630kVA to 1250kVA. The total capacity of distributed photovoltaic power is 3MW, the total capacity of energy storage devices is 2MWh, the maximum charging power of energy storage is 1MW, the maximum charging power of commercial charging stations is 1.2MW, and the power reduction capacity for flexible air conditioning loads is 300kW.

[0042] The threshold used in this embodiment is as follows: The upper limit threshold for node voltage is 1.07 pu, and the lower limit threshold for node voltage is 0.93 pu; the safe threshold for branch current is 90% of the long-term allowable current carrying capacity of the corresponding branch; the safe threshold for transformer load rate is 90%; the reverse power flow threshold is 20% of the rated capacity of the corresponding grid connection point; the maximum number of switching actions threshold is 4 times; the data time synchronization error threshold is 1 second; the preset reliability threshold corresponding to the historical response success rate is 85%; when the actual response of flexible resources reaches 90% of the target response, the preset response condition is determined to be met; the protection upper and lower level coordination time threshold is 0.3 seconds; the power flow projection iteration number threshold is 5 times; the setting group switching confirmation time threshold is 10 seconds; and the post-reconstruction review time window is 60 seconds.

[0043] Working principle of Example 1: The working principle of this embodiment includes the following steps.

[0044] S1: Multi-source data acquisition and consistency verification. Data access module 1 acquires distribution network topology, switch status, node voltage, branch current, active power, reactive power, distributed photovoltaic output, energy storage status, charging load status, air conditioning flexible load status, protection setting groups, and historical execution feedback data, and performs time synchronization and consistency verification on the above data. When the switch status data is inconsistent with the power flow direction, node voltage correlation, or branch current balance relationship, the corresponding feeder segment is marked as a topology uncertainty segment, and this segment is prohibited from participating in dynamic reconfiguration. This step avoids generating reconfiguration schemes based on incorrect topology or abnormal measurement data, improving the reliability of input data.

[0045] S2: Constructing the Node Flexible Operation Envelope. Envelope construction module 2 calculates the active power up-adjustment boundary, active power down-adjustment boundary, reactive power up-adjustment boundary, and reactive power down-adjustment boundary for each distribution node based on the distributed photovoltaic, energy storage, charging load, and air conditioning flexible load connected to each distribution node, generating the node flexible operation envelope. For photovoltaic access nodes, active power down-adjustment capability includes the photovoltaic power that can be limited, the energy storage power that can be charged, and the charging load that can increase its capacity; reactive power adjustment capability includes the remaining reactive power capacity of the photovoltaic inverter and the remaining reactive power capacity of the energy storage converter. For commercial charging station nodes, active power up-adjustment capability includes the charging load that can be derated and the air conditioning flexible load that can be reduced; active power down-adjustment capability includes the charging load that can increase its capacity. For resources with a historical response success rate below 85%, envelope construction module 2 lowers the available boundary corresponding to that resource; for resources that continuously meet the preset reliable response conditions, envelope construction module 2 increases the reliable response weight of that resource, but not exceeding the equipment's rated capacity. Through this step, the node flexible operation envelope is no longer an abstract constraint, but an executable boundary jointly determined by the field equipment status and historical response capability.

[0046] S3: Generate candidate reconfiguration topologies and perform flexible envelope pre-screening. The topology generation module 3 generates candidate reconfiguration topologies based on the current topology and the state of controllable switches. It first determines whether the candidate reconfiguration topologies meet the radial constraints, the constraint of no isolated distribution nodes, the constraint of prohibited operation switches, and the maximum number of switch actions threshold. After meeting the topology constraints, the topology generation module 3 calculates the active power offset and reactive power offset of each distribution node after switching from the current topology to the candidate reconfiguration topology, and obtains the node predicted power point. If the node predicted power point of any distribution node does not fall within the corresponding node's flexible operation envelope, the candidate reconfiguration topology is removed; if the node predicted power points of all distribution nodes fall within the corresponding node's flexible operation envelope, the candidate reconfiguration topology is marked as a flexible executable topology. For a certain candidate reconfiguration topology, if the active power reduction that the feeder end node needs to accept exceeds the sum of the energy storage rechargeable power and the charging load's increased acceptable power, the candidate reconfiguration topology is directly marked as a flexible non-executable topology and does not enter the power flow projection module 4. This step embodies the candidate topology pre-screening mechanism driven by the node's flexible operation envelope, which can reduce invalid power flow calculations and unexecutable reconfiguration schemes.

[0047] S4: Project power flow feasibility onto the flexible executable topology. Power flow projection module 4 performs AC power flow calculations on the flexible executable topology, identifying node voltage exceeding limits, branch current exceeding limits, transformer load rate exceeding limits, and reverse power flow exceeding limits. If no limits are exceeded, the candidate reconfigured topology is marked as a power flow executable topology. If limits are exceeded, the corresponding flexible resource correction rules are invoked according to the limit type, and AC power flow calculations are performed again after correction. When the voltage of a photovoltaic access node exceeds 1.07 pu, power flow projection module 4 prioritizes calling the photovoltaic inverter of that node to absorb reactive power; if reverse power flow still exceeds limits after reactive power absorption, power flow projection module 4 increases the charging power of adjacent energy storage devices and increases the power capacity accepted by the charging station. If the node voltage is below 0.93 pu, energy storage discharge, distributed photovoltaic inverter reactive power support, and charging load derating are prioritized. If the branch current or transformer load rate exceeds the safety threshold, charging load adjustment, air conditioning flexible load response, and energy storage discharge are invoked. If the power flow feasible region is still not satisfied after flexible resource correction, the power flow projection module 4 performs local topology fine-tuning, adjusting the state of segment switches or tie switches without disrupting the radial constraints, and ensuring that the predicted power points of the nodes after switch fine-tuning do not exceed the corresponding node's flexible operating envelope. If the power flow feasible region is still not satisfied after 5 projection iterations, the candidate reconstructed topology is eliminated. This step improves the traditional direct elimination method after power flow verification to power flow feasibility projection correction based on the node's flexible operating envelope, thereby improving the utilization rate of candidate topologies and the distributed photovoltaic absorption capacity.

[0048] S5: Perform protection coordination verification on the executable topology of the power flow. Protection verification module 5 generates preset fault scenarios for the executable topology of the power flow. These preset fault scenarios include feeder head faults, feeder end faults, branch line faults, low-voltage side faults of distribution transformers, and faults near distributed photovoltaic access points. Protection verification module 5 calculates the short-circuit current path and protection device operating time limits under each preset fault scenario, and determines whether the selectivity margin of the upper and lower level protections meets the protection coordination time threshold. The protection selectivity margin is the difference between the operating time limits of the upper and lower level protections minus the 0.3-second coordination time threshold. If all preset fault scenarios meet the protection selectivity requirements, the candidate reconfigurable topology is marked as a protection executable topology; if there is a fault scenario with a protection selectivity margin less than zero, the candidate reconfigurable topology is marked as a protection correction topology, and the corresponding mismatched protection device is marked. This step can prevent over-level tripping, protection failure to operate, or protection maloperation after reconfiguration.

[0049] S6: Perform adaptive matching of protection setting groups. Matching module 6, for the protection topology to be corrected, searches for spare protection setting groups of relevant protection devices, determines whether the operating current setting of the candidate protection setting group is greater than the maximum load current and less than the minimum short-circuit current, and determines whether the operating time limits of the upper and lower level protections meet the protection selectivity requirements after the protection setting group is activated. If a candidate protection setting group that meets the conditions exists, the setting group is scored based on short-circuit current identification margin, protection selectivity margin, number of setting group switching, and setting group switching risk. The candidate protection setting group with the highest score is selected as the target protection setting group, and the protection topology to be corrected is converted into a protection executable topology. If no candidate protection setting group that meets the conditions exists, the candidate topology to be reconstructed is eliminated. Taking a feeder end fault as an example, when the protection selectivity margin between the lower-level protection and the upper-level protection of the current protection setting group is insufficient, matching module 6 searches for spare protection setting groups of the corresponding ring main unit protection device and feeder protection device, and selects the setting group with the operating current setting greater than the maximum load current and less than the minimum short-circuit current, and with the largest protection selectivity margin. This step enables the partial protection of the topology to be modified to be transformed into a protection executable topology, expanding the range of available dynamic reconfiguration schemes.

[0050] S7: Determine the target topology for reconfiguration and generate coordinated scheduling instructions. The scheduling decision module 7 calculates a comprehensive evaluation value for all executable topologies. This comprehensive evaluation value is determined based on factors such as network loss reduction, voltage deviation improvement, distributed photovoltaic absorption enhancement, protection selectivity margin, remaining flexible resource capacity, switch action cost, and user response cost. The scheduling decision module 7 selects the candidate topology with the highest comprehensive evaluation value as the target topology for reconfiguration and generates instructions for energy storage charging, photovoltaic inverter reactive power absorption, increased charging load acceptance, air conditioning flexible load response, protection setting group switching, and tie switch switching. Through this step, topology reconfiguration, energy storage scheduling, reactive power regulation, charging load adjustment, flexible load response, and protection setting group switching are unified into coordinated scheduling instructions, preventing the fragmentation of various control tasks.

[0051] S8: Execute the reconfiguration command according to the safe timing sequence. The timing control module 8 first preloads the target protection setting group to the corresponding protection device, and then performs flexible resource pre-adjustment. Flexible resource pre-adjustment includes increasing the energy storage charging power, controlling the photovoltaic inverter to absorb reactive power, increasing the charging station's power acceptance, and calling the air conditioning flexible load response. When the actual response of the flexible resources reaches 90% of the target response, the timing control module 8 engages the target protection setting group and confirms that the setting group switching is successful. After confirming that the target protection setting group is successfully engaged, the timing control module 8 executes the tie switch and sectionalizing switch switching commands to form the target reconfiguration topology. If the setting group switching is unsuccessful, the timing control module 8 prohibits the execution of switch switching that would change the fault current path. This step, through the sequential control of setting preloading, flexible resource pre-adjustment, setting engagement confirmation, and switch switching, avoids the risk of protection mismatch window and power flow impact.

[0052] S9: Post-Reconstruction Verification and Rollback. After the target reconstructed topology is formed, the system re-collects node voltages, branch currents, transformer load rates, reverse power flow, and protection device status to determine whether the actual operating state meets the power flow feasible region and protection selectivity requirements. If the node voltages, branch currents, transformer load rates, and reverse power flow all meet the corresponding preset safety thresholds, and the protection selectivity margin is not less than zero, the reconstruction is considered successful. If the post-reconstruction verification fails, or if abnormalities occur such as switch failure, protection setting group switching failure, insufficient energy storage response, charging load refusal to respond, or insufficient air conditioning flexible load response, the system executes a backup topology switching command or restores to the safe topology. This step improves the operational safety and fault handling capabilities of dynamic reconstruction.

[0053] S10: Execute Feedback Update. The feedback update module 9 updates the node flexible operation envelope, candidate reconfiguration topology screening rules, candidate topology scoring rules, protection setting group matching priority, protection setting group matching rules, and comprehensive scheduling decision weights based on the actual execution results. If the actual response of a distribution node's energy storage or charging load is lower than the target response for several consecutive scheduling cycles, the feedback update module 9 reduces the node flexible operation envelope boundary for subsequent scheduling cycles. If a protection setting group switching fails or the protection verification result is unstable, the feedback update module 9 reduces the matching priority of that setting group. If a certain type of topology exhibits better network loss reduction and voltage improvement effects than predicted in actual operation, the feedback update module 9 increases the corresponding topology screening rules and scheduling decision weights. This step enables the system to continuously correct itself based on the actual response capability on-site, avoiding distortion of the static model.

[0054] Technical effects of Example 1: First, by using the flexible operation envelope of nodes to drive the pre-screening of candidate reconfiguration topologies, the candidate reconfiguration topologies have met the resource carrying capacity requirements of the node side before entering the power flow calculation, reducing the number of unexecutable topologies entering the subsequent calculation process.

[0055] Secondly, by using a power flow feasibility projection mechanism based on over-limit types, corresponding flexible resources are invoked to make corrections when node voltage exceeds the upper limit, node voltage exceeds the lower limit, branch current exceeds the limit, transformer is overloaded, and reverse power flow exceeds the limit, thereby improving the topology availability in power flow over-limit scenarios.

[0056] Third, by reconstructing the topology and using an adaptive matching mechanism with the protection setting group, the protection topology to be modified can be transformed into an executable topology after meeting the requirements of operating current and operating time, reducing the situation where candidate topologies are directly eliminated due to protection mismatch.

[0057] Fourth, by preloading protection setting groups, pre-adjusting flexible resources, confirming the input of protection setting groups, and controlling the execution timing of switch switching, the risk of protection mismatch and power flow impact during topology switching is reduced.

[0058] Fifth, by continuously updating the flexible operation envelope of the execution feedback-driven nodes, the matching priority of the protection setting group, and the comprehensive scheduling decision weight, the dynamic reconfiguration strategy of the distribution network can adapt to the fluctuations of distributed photovoltaics, changes in energy storage status, uncertainties in charging load, and differences in flexible load response.

[0059] Example 2, based on Example 1, further illustrates the specific implementation of the data access module 1, envelope construction module 2, topology generation module 3, and power flow projection module 4.

[0060] Data access module 1 is used to collect, clean, and synchronize the data required for dynamic reconfiguration of the distribution network. Data access module 1 is used to access the distribution network's topology data, measurement data, distributed power source data, energy storage data, charging load data, flexible load data, and protection setting data, and performs consistency verification processing on the accessed data.

[0061] The topology data access unit is used to collect the connection relationships between feeders, buses, distribution transformers, sectionalizing switches, tie switches, circuit breakers, ring main units, distributed power supply access points, energy storage access points, charging load access points, and flexible load access points, and generate a distribution network topology map.

[0062] The measurement data access unit is used to collect node voltage, branch current, active power, reactive power, power factor, transformer load rate, reverse power flow, and switch status.

[0063] The distributed power data access unit is used to collect real-time output, predicted output, inverter rated capacity, current active power output, available reactive power capacity, and finiteable power of distributed photovoltaic or distributed wind power.

[0064] The energy storage data access unit is used to collect the energy storage device's state of charge, rated capacity, maximum charging power, maximum discharging power, charging and discharging efficiency, remaining rechargeable capacity, and remaining discharging capacity.

[0065] The charging load data access unit is used to collect the current charging power of the charging pile, the estimated departure time, the target charging capacity, the derated power, the delay time, and the user's charging constraints.

[0066] The flexible load data access unit is used to collect data on the power reduction, response time, recovery power, response cost, and historical response success rate of interruptible loads, transferable loads, air conditioning loads, heat pump loads, and industrial adjustable loads.

[0067] The protection setting data access unit is used to collect information such as the protection device number, the feeder section where the protection device is located, the current protection setting group, the standby protection setting group, the operating current setting, the operating time setting, the reclosing time, the coordination relationship between upper and lower level protections, and the setting group switching status.

[0068] The data consistency verification unit is used to determine whether the data is consistent based on the switch status, power flow direction, node voltage correlation, and branch current balance. When the topology status data is inconsistent with the physical measurement data, the corresponding data is marked as pending confirmation, and direct reconstruction based on this data is prohibited. In this embodiment, the data time synchronization error threshold is 1 second; when the current balance deviation at both ends of the same branch exceeds 5% of the branch's rated current, or the node power balance deviation exceeds 5% of the node's reference load, the relevant data enters the pending confirmation state.

[0069] Through the above data access methods, the operational dataset includes not only topology and measurement data, but also distributed power sources, energy storage, charging loads, flexible loads, and protection setting data, providing a unified data foundation for the construction of node flexible operation envelopes, candidate reconfiguration topology screening, and power flow projection correction.

[0070] Envelope construction module 2 is used to form the boundary of the power change that the distribution node can accept during the current scheduling cycle based on the adjustable resources associated with each distribution node. Envelope construction module 2 includes a resource ownership identification unit 21, an adjustable capacity calculation unit 22, an envelope boundary generation unit 23, and a reliable response correction unit 24.

[0071] The resource ownership identification unit 21 is used to determine the distribution node to which distributed power sources, energy storage devices, charging loads, and flexible loads belong based on the operational dataset, and to uniquely assign the same adjustable resource to the distribution node corresponding to its electrical access point within the same scheduling cycle, thus obtaining the node resource ownership relationship. For cross-regional transferable loads, the actual access point or the receiving point specified by the scheduling instruction is used as the unique ownership point within the same scheduling cycle, avoiding the same resource being repeatedly counted as the adjustable capacity of multiple distribution nodes.

[0072] Adjustable capacity calculation unit 22 is connected to resource ownership identification unit 21 and is used to calculate the active power up-adjustment capacity, active power down-adjustment capacity, reactive power up-adjustment capacity and reactive power down-adjustment capacity of each distribution node based on the node resource ownership relationship and adjustable resource operation data, so as to obtain node adjustable capacity data.

[0073] The active power up-adjustment capability of a distribution node is determined at least by the dischargeable power of energy storage, the power reduction of interruptible loads, the derated power of charging loads, and the power transferred out by transferable loads. The active power down-adjustment capability of a distribution node is determined at least by the chargeable power of energy storage, the power that distributed generation can limit, the power that charging loads can increase, and the power transferred in by transferable loads. The reactive power up-adjustment capability and reactive power down-adjustment capability of a distribution node are determined at least by the remaining reactive power capacity of the distributed generation inverter, the adjustable capacity of the reactive power compensation device, and the reactive power capacity of the energy storage converter.

[0074] Envelope boundary generation unit 23 is connected to adjustable capacity calculation unit 22 and is used to generate the upper boundary of active power, the lower boundary of active power, the upper boundary of reactive power, the lower boundary of reactive power, and the active and reactive capacity coupling constraints of each distribution node based on the node adjustable capacity data, so as to obtain the node flexible operation envelope.

[0075] For the The power distribution node is at the first The flexible operation envelope of a node over a scheduling cycle can be expressed by the following formula: ; in, Indicates the first The power distribution node is at the first The flexible operation envelope of nodes in each scheduling cycle; This indicates the allowed adjusted active power, expressed in kW. This indicates the reactive power after adjustment, in kvar. This indicates the lower boundary of active power, in kW. This indicates the upper boundary of active power, in kW. This represents the lower boundary of reactive power, in kvar. This represents the upper boundary of reactive power, in kvar. This represents the baseline active power, in kW. This represents the baseline reactive power, expressed in kvar. This represents the normalized active power scale, in kW, and is greater than 0. This represents the reactive power normalization scale, in kvar, and is greater than 0. The capacity coupling confidence factor is a dimensionless parameter. This represents the hyperbolic tangent function.

[0076] In the above formula, the power difference divided by the corresponding normalized scale results in a dimensionless quantity. Both the input and output of the square root function and the hyperbolic tangent function are dimensionless, thus achieving dimensional matching. This formula expresses the capacity coupling relationship between active and reactive power through the square root function and the hyperbolic tangent function, avoiding the problem where active and reactive power individually satisfy the boundary conditions but exceed the equipment capacity when combined.

[0077] The upper and lower boundaries of reactive power are generated based on the remaining reactive capacity of the distributed power inverter, the adjustable capacity of the reactive power compensation device, and the reactive power capacity of the energy storage converter. When the inverter or energy storage converter participates in both active and reactive power regulation, the capacity coupling constraint in the formula for the node flexible operation envelope is used to limit the combination of active and reactive power regulation to not exceeding the corresponding equipment capacity.

[0078] The trusted response correction unit 24 is connected to the envelope boundary generation unit 23 and is used to correct the node's flexible operation envelope based on historical execution results. The trusted response correction coefficient can be expressed by the following formula: ; in, Indicates the first The adjustable resource is in the first The reliable response correction coefficient for each scheduling cycle is a dimensionless parameter. This represents a limiting function, used to restrict the calculation results to a certain range. Between 1 and 1; Represents an exponential function; Represents the natural logarithm function; Indicates the first The response sensitivity coefficient of an adjustable resource is a dimensionless parameter. Indicates the first The historical response success rate of each adjustable resource is a dimensionless parameter. This represents a preset confidence threshold, which is set to 0.85 in this embodiment; Indicates the first The absolute value of the historical response deviation of each adjustable resource is a dimensionless parameter, and ≥0; This represents the minimum reliable response correction factor, which is 0.60 in this embodiment.

[0079] In the above formulas, the inputs to the exponential and logarithmic functions are dimensionless quantities, and the outputs are dimensionless correction coefficients. When the historical response success rate of a certain adjustable resource is lower than 0.85, the trusted response correction unit 24 reduces the available boundary of that resource in the node flexible operation envelope. The reduction can be 20% of the rated adjustment capacity of the resource. When a certain adjustable resource meets the preset trusted response conditions for three consecutive scheduling cycles, the trusted response weight of the corresponding adjustable resource is increased. The preset trusted response conditions include the actual response quantity reaching more than 90% of the target response quantity, and the response delay not exceeding 60 seconds. The increased node flexible operation envelope must not exceed the rated capacity of the corresponding adjustable resource.

[0080] After completing the calculation of the node flexible operation envelope, the envelope construction module 2 outputs the node flexible operation envelope to the topology generation module 3 and the power flow projection module 4, which are used to constrain candidate topology generation and power flow executability judgment. Thus, the node flexible operation envelope serves both as a prerequisite screening condition for candidate topology reconstruction and as a constraint boundary for the resource correction amount when the power flow exceeds the limit.

[0081] Based on the above rules, the flexible operation envelope of a node is jointly determined by the energy storage state of charge, inverter capacity, charging load constraints, flexible load response capability, and historical response reliability, which can reflect the actual executable power carrying capacity of the distribution node in the current dispatch cycle.

[0082] The topology generation module 3 is used to generate candidate reconstructed topologies that satisfy radial constraints and can be accommodated by the flexible operation envelope of nodes. The topology generation module 3 includes a topology graph modeling unit 31, a switch combination generation unit 32, a topology constraint judgment unit 33, a node power offset calculation unit 34, and an envelope filtering unit 35.

[0083] The topology modeling unit 31 is used to create a distribution network topology diagram including distribution nodes, branches, and controllable switches based on the operational dataset. The distribution network topology diagram can be represented as a graph structure consisting of a set of nodes, a set of branches, and a set of controllable switches. Distribution nodes represent busbars, load connection points, distributed power generation connection points, energy storage connection points, or charging load connection points. Branches represent feeder sections or transformer connection branches. Controllable switches include sectionalizing switches, tie switches, and circuit breakers.

[0084] The switch combination generation unit 32 is connected to the topology modeling unit 31 and is used to generate candidate switch combinations based on the current state of the controllable switches in the distribution network topology.

[0085] The topology constraint judgment unit 33 is connected to the switch combination generation unit 32, and is used to determine the candidate switch combinations that satisfy the radial operation constraint, the no-isolated distribution node constraint, the prohibited operation switch constraint, and the preset switch action constraint as candidate reconfigurable topology. The radial operation constraint includes not forming an unplanned closed loop; the no-isolated distribution node constraint includes not generating an isolated distribution node without power supply; the prohibited operation switch constraint includes not changing the state of the switch that is under maintenance, locked, or prohibited from operation by scheduling; the preset switch action constraint includes that the number of switch actions in the current scheduling cycle does not exceed 4 times.

[0086] The node power offset calculation unit 34 is connected to the topology constraint judgment unit 33. It is used to calculate the active power offset and reactive power offset of each distribution node after switching from the current topology to the candidate reconfiguration topology, and obtain the node predicted power point.

[0087] Envelope screening unit 35 is connected to node power offset calculation unit 34, and is used to determine candidate reconfigurable topologies whose predicted power points fall within the flexible operation envelope of the corresponding distribution node as flexible executable topologies. The flexibility screening margin of the candidate reconfigurable topology can be expressed by the following formula: ; in, The flexible screening margin of the s-th candidate topology reconstruction is represented by a dimensionless parameter. Represents the set of power distribution nodes; Indicates the s-th candidate topology under the th... The predicted active power of each distribution node in the τth dispatch cycle, in kW; Let represent the predicted reactive power of the i-th distribution node in the τ-th scheduling cycle under the s-th candidate reconfiguration topology, in kvar; the meanings of the other symbols are the same as those in the formula for the node flexible operation envelope. This indicates taking the maximum value of the terms within the parentheses. This means first identifying the most severe envelope out-of-bounds item at each distribution node, and then finding the most severe envelope out-of-bounds degree among all distribution nodes in the entire network.

[0088] when When ≤0, it means that the predicted power points of all distribution nodes under the s-th candidate reconfiguration topology fall within the corresponding node's flexible operation envelope, and this candidate reconfiguration topology is determined to be a flexible executable topology; when When the value is greater than 0, it indicates that at least one distribution node cannot absorb the power shift after the topology switch, and the candidate topology for reconfiguration is eliminated. The above formula simultaneously considers the upper and lower boundaries of active power, the upper and lower boundaries of reactive power, and the coupling constraints of active and reactive power capacity, avoiding incomplete screening caused by considering only a single constraint.

[0089] After generating multiple candidate topologies, the topology generation module 3 ranks them based on load recovery ratio, number of switching operations, feeder load balancing degree, node voltage deviation, and the adjustability margin of flexible resources, and sends the ranking results to the power flow projection module 4. Ranking indicators include expected reduction in network loss, improvement in voltage deviation, increase in distributed generation absorption, number of switching operations, and remaining adjustability of flexible resources. The ranking results are used to improve the efficiency of subsequent power flow projection calculations, prioritizing flexible executable topologies with higher overall potential.

[0090] With this topology generation method, only candidate reconstructed topologies whose node power offsets fall within the corresponding node's flexible operating envelope can enter the subsequent power flow projection process. This makes node-side adjustment capability a mandatory prerequisite for dynamic reconstruction, reducing invalid schemes where the topology can be switched but the nodes cannot accept it.

[0091] The power flow projection module 4 is used to perform AC power flow calculations on the flexible executable topology, and when the flexible executable topology has operational limitations, it projects it to the power flow feasible region through flexible resource correction and local topology fine-tuning. The power flow projection module 4 includes a power flow calculation unit 41, a limitation identification unit 42, a resource correction unit 43, a switch fine-tuning unit 44, and a projection iteration unit 45.

[0092] The power flow calculation unit 41 receives the flexible executable topology and performs power flow calculations on it to obtain the power flow calculation results. The power flow calculation results include node voltages, branch currents, transformer load rates, reverse power flow, and network losses.

[0093] The over-limit identification unit 42 is connected to the power flow calculation unit 41 and is used to identify the over-limit objects and types of power flow based on the power flow calculation results. Over-limit objects include at least one of distribution nodes, branches, transformers, and grid connection points. Over-limit types include at least one of node voltage over-limit, branch current over-limit, transformer load rate over-limit, and reverse power flow over-limit; furthermore, the over-limit identification unit 42 also identifies the absorption risk caused by the limited output of distributed generation sources.

[0094] In this embodiment, the upper limit threshold of node voltage is 1.07 pu, and the lower limit threshold of node voltage is 0.93 pu; the safe threshold of branch current is 90% of the long-term allowable current carrying capacity of the corresponding branch; the safe threshold of transformer load rate is 90%; the reverse power flow threshold is 20% of the rated capacity of the corresponding grid connection point; and the threshold of projection iteration number is 5 times.

[0095] Resource correction unit 43 is connected to limit violation identification unit 42, and is used to generate resource correction amount by using the node flexible operation envelope as the constraint boundary of resource correction amount when there is a power flow limit violation in the flexible executable topology. Figure 2 As shown, the resource correction unit 43 includes an over-limit type dispatch subunit 431, a voltage over-limit correction subunit 432, a voltage over-limit correction subunit 433, an overload correction subunit 434, and a reverse power flow correction subunit 435.

[0096] The over-limit type assignment subunit 431 is used to assign each power flow over-limit object to a voltage upper limit, voltage lower limit, overload, or reverse power flow category according to a preset priority. The same power flow over-limit object is assigned to only one category within the same iteration round. The preset priority is as follows: node voltage upper limit and node voltage lower limit categories have the highest priority, followed by overload, then reverse power flow. Distributed source absorption risk is included in the correction as an ancillary risk associated with voltage upper limit or reverse power flow categories. Overload categories include branch current over-limit and / or transformer load rate over-limit. Through this assignment method, multiple different power flow over-limit objects can be processed separately within the same iteration round, but the same power flow over-limit object will not be repeatedly assigned to multiple categories, avoiding overlapping correction areas and repeated resource calls.

[0097] The voltage limit exceedance correction subunit 432 is connected to the limit exceedance type dispatch subunit 431. It is used to generate at least one resource correction amount among distributed generation reactive power absorption, energy storage charging, and distributed generation limiting when the power flow limit exceedance object belongs to the voltage limit exceedance category. Specifically, when the node voltage exceeds 1.07 pu, the distributed generation inverters of the exceeding distribution node and adjacent distribution nodes are preferentially called to absorb reactive power; if the limit exceedance cannot be eliminated after reactive power absorption, the energy storage charging power is increased or the active power output of the distributed generation is reduced.

[0098] The voltage lower limit correction subunit 433 is connected to the over-limit type dispatch subunit 431. When the power flow over-limit object belongs to the voltage lower limit category, it generates at least one resource correction amount among energy storage discharge, distributed generation reactive power support, and charging load derating. Specifically, when the node voltage is below 0.93 pu, the energy storage discharge of the over-limit distribution node and its upstream distribution node is preferentially invoked; if the over-limit cannot be eliminated, the reactive power support of the distributed generation inverter is increased or the deferred charging load is reduced.

[0099] The overload correction subunit 434 is connected to the overload type dispatch subunit 431, and is used to generate at least one resource correction amount among charging load adjustment, flexible load response, and energy storage discharge when the power flow overload object belongs to the overload category. Specifically, when the branch current exceeds 90% of the corresponding branch's long-term allowable current carrying capacity, the receiving end charging load power and interruptible load power are reduced first; if the overload still cannot be eliminated, the receiving end energy storage discharge is invoked to reduce the power supply pressure on the upstream feeder. When the transformer load rate exceeds 90%, low-priority flexible loads and charging loads are reduced first; if the overload still cannot be eliminated, part of the load is transferred to the adjacent feeder through the tie switch.

[0100] The reverse power flow correction subunit 435 is connected to the over-limit type dispatch subunit 431, and is used to generate at least one resource correction amount among energy storage charging, charging load increase acceptance power, flexible load response, and distributed power generation limitation when the over-limit object belongs to the reverse power flow category. Specifically, when the reverse power flow exceeds 20% of the rated capacity of the corresponding grid connection point, the energy storage charging power and charging load increase acceptance power are increased first; if the over-limit cannot be eliminated, the output of distributed power sources is reduced.

[0101] The switch fine-tuning unit 44 is connected to the resource correction unit 43. It is used to generate a switch fine-tuning scheme that does not violate radial operation constraints and does not cause the predicted power point of the node after switch fine-tuning to exceed the node flexible operation envelope of the corresponding distribution node when the resource correction amount cannot eliminate power flow exceedance. The switch fine-tuning scheme includes partial replacement of the states of some segment switches and tie switches in the candidate topology reconfiguration. Local topology fine-tuning must not form unplanned closed loops, must not create isolated distribution nodes without power supply, must not change the state of prohibited switches, and must not cause the number of switch actions to exceed four within the current scheduling cycle.

[0102] The projection iteration unit 45 connects the resource correction unit 43, the switch fine-tuning unit 44, and the power flow calculation unit 41. It is used to adjust the corresponding adjustable resources according to the resource correction amount and / or adjust the corresponding controllable switches according to the switch fine-tuning scheme, and then re-trigger power flow calculation until the node voltage, branch current, transformer load rate, and reverse power flow of the topology after resource correction and / or switch fine-tuning meet the corresponding preset safety thresholds, and then determine it as a power flow executable topology. The power flow feasibility projection correction can be expressed by the following formula: ; in, This represents the target correction scheme corresponding to the s-th flexible executable topology, including resource correction amount and switch fine-tuning variable; This represents the function to minimize the solution; Indicates the variable to be corrected; This represents the constraint set corresponding to the s-th flexible executable topology, which includes node flexible operation envelope constraints, radial operation constraints, constraints on no isolated distribution nodes, and preset switching action constraints. Indicates the correction variable and topological state The normalized vector of the power flow that is generated below the limit; This represents the topology state of the s-th flexible executable topology; Represents a L2 norm function; This indicates a positive number to prevent the denominator from being zero; in this embodiment, it is taken as 0.01. Represents the Sigmoid function; This represents the projection sensitivity coefficient, which is a dimensionless parameter. Indicates the correction variable The envelope margin, relative to the flexible operation envelope of the nodes, is a dimensionless parameter.

[0103] In the above formula, Each element is obtained by normalizing node voltage, branch current, transformer load rate, and reverse power flow according to the corresponding preset safety threshold. Therefore, the L2 norm is dimensionless; the denominator is also dimensionless, resulting in overall dimension matching. The above formula, through minimization functions, L2 norm functions, and sigmoid functions, minimizes the degree of power flow exceeding limits by minimizing resource adjustments and switching fine-tuning while satisfying the node flexible operation envelope and topology constraints, thereby correcting the flexible executable topology to a power flow executable topology.

[0104] If the power flow feasible region is still not satisfied after 5 projection iterations, the candidate reconstructed topology is marked as a power flow inoperable topology and is prohibited from entering the subsequent protection verification process. When the candidate topology satisfies the above power flow constraints, the power flow projection module 4 determines the candidate topology as a power flow executable candidate topology; when the candidate topology does not satisfy the above power flow constraints, the power flow projection module 4, in conjunction with the resource correction unit 43, corrects the node flexible resources, or determines the candidate topology as a power flow inoperable candidate topology.

[0105] The working principle of this embodiment is as follows: First, the data access module 1 forms a reliable operational dataset. Then, the envelope construction module 2 generates a node flexible operational envelope based on the actual adjustability of the associated resources of the distribution node and the reliability of historical responses. Subsequently, the topology generation module 3 determines whether the predicted power point of the node after topology switching falls into the corresponding node flexible operational envelope during the candidate reconfiguration topology generation stage. Only candidate reconfiguration topologies that meet the node flexible acceptance conditions can be determined as flexible executable topologies. Finally, the power flow projection module 4 performs power flow calculations on the flexible executable topology. When power flow exceeds the limit, the node flexible operational envelope is used as the boundary of resource correction. Distributed power sources, energy storage, charging loads, and flexible loads are called for correction according to the power flow exceedance type. If necessary, local switch fine-tuning is performed until a power flow executable topology is formed.

[0106] This embodiment uses the node flexible operation envelope simultaneously for both the preliminary screening of candidate reconfiguration topologies and the resource correction constraints after power flow exceedances, ensuring that the node flexible operation envelope spans both the "candidate topology generation - power flow projection correction" stages. This avoids unacceptable candidate reconfiguration topologies from entering subsequent power flow calculations, reducing unnecessary computation. Simultaneously, it prioritizes the use of existing flexible resources for correction when power flow exceedances occur, avoiding simple elimination of candidate reconfiguration topologies, thus improving candidate topology availability, distributed generation absorption capacity, and the engineering feasibility of dynamic reconfiguration schemes for distribution networks.

[0107] Example 3, based on Examples 1 and 2, further illustrates the processing procedure after a power flow executable topology enters the protection security verification. This example focuses on solving the problem that while a reconfigured topology is executable at the power flow level, it may not meet the selectivity requirements of upper and lower level protections at the relay protection level. It further explains the specific implementation methods of protection setting group matching, target reconfiguration topology decision-making, security execution timing, and execution feedback update.

[0108] The protection verification module 5 is used to perform relay protection collaborative verification on the executable topology of power flow, and to determine whether the candidate topology meets the protection selectivity when a fault occurs. The protection verification module 5 includes a fault scenario generation unit 51, a short-circuit current calculation unit 52, a fault path identification unit 53, an action time limit calculation unit 54, and a protection selectivity judgment unit 55.

[0109] The fault scenario generation unit 51 is used to generate preset fault scenarios based on the executable power flow topology. The preset fault scenarios include feeder head faults, feeder end faults, branch line faults, transformer low-voltage side faults, and faults near the distributed power source access point. By generating the above fault scenarios under the executable power flow topology, the main locations where the short-circuit current path may change after topology reconfiguration can be covered.

[0110] The short-circuit current calculation unit 52 is connected to the fault scenario generation unit 51 and is used to calculate the short-circuit current under each preset fault scenario to obtain short-circuit current data. The short-circuit current data includes the minimum short-circuit current, the maximum short-circuit current, and the path through which the short-circuit current flows. The minimum short-circuit current is used to determine whether the protection device can operate reliably, and the maximum short-circuit current is used to determine the withstand capability of the protection device and the switching equipment.

[0111] The fault path identification unit 53 is connected to the short-circuit current calculation unit 52. It is used to identify the switching equipment, protection devices, feeder sections, and upper and lower level protection relationships through which the short-circuit current flows based on the short-circuit current data and protection setting data, thereby obtaining fault current path data. The fault current path data includes at least the protection device number, the feeder section where the protection device is located, the coordination relationship between upper and lower level protection, the fault scenario number, and the direction of fault current flow.

[0112] The operating time calculation unit 54 is connected to the fault path identification unit 53 and is used to calculate the operating time of each protection device based on the fault current path data and protection setting data. The operating time is calculated based on the operating current setting, operating time setting, reclosing time, and corresponding short-circuit current in the current protection setting group of the protection device.

[0113] The protection selectivity judgment unit 55 is connected to the action time limit calculation unit 54, and is used to determine whether the power flow executable topology meets the protection selectivity requirements based on the action time limits of the upper and lower level protection devices and the preset coordination time threshold. In this embodiment, the preset coordination time threshold is 0.3s. The protection selectivity margin is determined based on the action time of the upper level protection, the action time of the lower level protection, and the preset coordination time threshold. When there is an upper and lower level protection relationship with a protection selectivity margin less than 0 under any preset fault scenario, it is determined that the power flow executable topology does not meet the protection selectivity requirements.

[0114] When all preset fault scenarios and all hierarchical protection relationships satisfy the protection selectivity margin of not less than 0, the protection selectivity judgment unit 55 marks the power flow executable topology and outputs it as a protection executable topology. When there is a protection selectivity margin of less than 0, the protection selectivity judgment unit 55 marks the power flow executable topology and outputs it as a protection topology to be corrected, and marks the corresponding mismatch protection device.

[0115] When a candidate topology meets the protection adaptability requirements, the protection verification module 5 outputs the candidate topology to the matching module 6; when a candidate topology does not meet the protection adaptability requirements, the protection verification module 5 determines that the candidate topology needs protection setting matching or protection coordination relationship adjustment, and sends the corresponding verification result to the matching module 6. Through this recorded result, the subsequent matching module 6 can directly locate the protection devices that need protection setting group matching, avoiding indiscriminate searching of all protection devices.

[0116] By using the protection verification module 5, the relay protection selectivity is set as a mandatory verification condition before the candidate topology is executed, which can avoid generating a reconfiguration scheme that is safe for power flow but not for protection.

[0117] Matching module 6 is used to match protection setting groups based on short-circuit current, maximum load current, and protection operating time when protection mismatch exists in the candidate topology. Matching module 6 includes a setting group retrieval unit 61, an operating current adaptation unit 62, an operating time adaptation unit 63, a protection verification unit 64, and a matching output unit 65.

[0118] The setting group retrieval unit 61 is used to retrieve a backup protection setting group from the protection setting data according to the mismatch protection device corresponding to the topology to be corrected. The backup protection setting group includes protection setting groups formed by different combinations of operating current settings, different operating time settings, and different reclosing times.

[0119] The operating current adaptation unit 62 is connected to the setting group retrieval unit 61. It is used to filter candidate protection setting groups from the standby protection setting group based on the maximum load current determined by the operating dataset under the protection topology to be corrected, and the minimum short-circuit current determined by the short-circuit current data. The operating current setting of the candidate protection setting group is greater than the maximum load current and less than the minimum short-circuit current. This condition reduces the risk of protection maloperation caused by the maximum load current and ensures reliable operation of the protection device under the minimum short-circuit current.

[0120] The operating time adaptation unit 63 is connected to the operating current adaptation unit 62. It is used to calculate the operating time of the upper and lower level protection devices based on the candidate protection setting groups and to screen the candidate protection setting groups that meet the protection selectivity requirements. The preset coordination time threshold of 0.3s is still used for judgment during the operating time adaptation. That is, after the candidate protection setting groups are put into use, the protection selectivity margin under each preset fault scenario is not less than 0.

[0121] Matching module 6 performs a matching score on each candidate protection setting group based on the short-circuit current level, protection installation point location, protection action time, coordination relationship between upper and lower level protections, and protection setting adjustment range under the candidate topology. The setting group matching score can be expressed by the following formula: ; in, represents the value group matching score of the r-th candidate protection value group, which is a dimensionless parameter; Represents the Sigmoid function; Indicates the first The operating current setting of the mismatch protection device when using the r-th candidate protection setting group is expressed in A. Indicates the first The maximum load current of a mismatch protection device under the protection topology to be corrected, in amperes (A); Indicates the first The minimum short-circuit current within the protection range of each mismatch protection device, in amperes (A). Indicates the first The minimum protection selectivity margin of a mismatch protection device after adopting the r-th candidate protection setting group, in seconds; This represents the preset engagement time threshold, which is 0.3s in this embodiment; This represents the number of protection devices that need to be switched when adopting the r-th candidate protection setting group, and is a dimensionless parameter; represents the normalized value of the switching risk for the r-th candidate protection setting group, which is a dimensionless parameter.

[0122] In the above formula, the two current fractions and The numerator and denominator are both A, time fraction The numerator and denominator are both in units of s, therefore these fractions are all dimensionless. The denominator of the overall formula for the fixed-value group matching score contains... and All are dimensionless quantities, thus ensuring overall dimensionality matching. Two sigmoid functions are used to evaluate the safety margin of the operating current setting relative to the maximum load current and the minimum short-circuit current, respectively; the hyperbolic tangent function is used to evaluate the protection selectivity margin; and the natural logarithm function is used to suppress the number of setting group switching and the switching risk.

[0123] When a candidate protection setting group meets the following conditions: the operating current setting is greater than the maximum load current and less than the minimum short-circuit current, and the protection selectivity margin is not less than 0, the candidate protection setting group is determined as an available protection setting group. Among multiple available protection setting groups, the matching module 6 selects... The largest candidate protection setting group is taken as the target protection setting group. When the topology to be corrected involves multiple mismatched protection devices, the setting group matching score of the candidate protection setting group corresponding to each mismatched protection device is calculated according to the above formula, and the target protection setting group is determined according to the combination in which all mismatched protection devices pass the protection review.

[0124] The protection verification unit 64 is connected to the operating time adaptation unit 63, which is used to re-verify the short-circuit current path and operating time of each of the screened candidate protection setting groups, and determine the candidate protection setting groups that pass the verification as usable protection setting groups. Protection verification includes re-performing short-circuit current calculation, operating time calculation, and protection selectivity judgment.

[0125] The matching output unit 65 is connected to the protection verification unit 64. It is used to determine the target protection setting group from the available protection setting groups according to a preset setting group selection rule, convert the protection topology to be corrected into a protection executable topology, and output the protection execution topology and the corresponding protection setting group switching instruction for the target protection setting group. When all candidate protection setting groups fail the protection verification, the matching module 6 marks the protection topology to be corrected as a protection non-executable topology and stops that candidate topology from entering the scheduling decision process.

[0126] Through matching module 6, the system does not simply eliminate candidate topologies when protection mismatch occurs. Instead, it uses existing backup protection setting groups to adaptively match the protection topologies to be corrected, transforming some protection topologies to be corrected into executable protection topologies, thereby expanding the range of available dynamic reconfiguration schemes.

[0127] The scheduling decision module 7 is used to determine the target reconfiguration topology from the protected executable topology and generate cooperative scheduling instructions. The scheduling decision module 7 includes a comprehensive evaluation unit, an action cost evaluation unit, a scheduling instruction generation unit, and an instruction conflict verification unit.

[0128] The comprehensive evaluation unit calculates the comprehensive evaluation value for each executable protection topology. The comprehensive evaluation value is determined based on the following indicators: network loss reduction, voltage improvement, distributed power source absorption improvement, protection safety margin, flexible resource remaining capacity, switching action cost, and user response cost. In this embodiment, the weights for network loss reduction, voltage improvement, distributed power source absorption improvement, protection safety margin, flexible resource remaining capacity, switching action cost, and user response cost are all set to 0.15. All indicators are normalized to the range of 0 to 1. The comprehensive evaluation unit selects the executable protection topology with the highest comprehensive evaluation value as the target reconstructed topology.

[0129] The action cost evaluation unit is used to evaluate the number of switching actions, the number of protection setting group switching actions, the energy storage charging and discharging depth, the flexible load call duration, and the charging load adjustment range involved in the candidate topology. In this embodiment, the threshold for the number of switching actions in the current scheduling cycle is 4, the threshold for the number of protection setting group switching actions is 3, the threshold for the continuous flexible load call duration is 30 minutes, and the threshold for the single adjustment range of the charging load is 30% of the rated charging power.

[0130] The scheduling instruction generation unit is used to generate switching instructions, energy storage charging and discharging instructions, distributed power reactive power regulation instructions, charging load derating or delay instructions, flexible load response instructions, and protection setting group switching instructions corresponding to the target reconfiguration topology. For protection executable topologies that do not require switching of protection setting groups, the protection setting group switching instruction can be an empty instruction, but the timing control module 8 still confirms the current protection setting group status.

[0131] The instruction conflict verification unit is used to verify whether there are execution conflicts between different instructions. If the protection setting group switching instruction has not been confirmed as completed, the execution of switch switching instructions that would change the fault current path is prohibited; if the flexible resource pre-adjustment has not reached the target response amount, the execution of load transfer instructions that would cause branch overload or voltage over-limit is prohibited. Through instruction conflict verification, execution conflicts between different controlled objects can be reduced.

[0132] The timing control module 8 is used to execute the collaborative scheduling instructions generated by the scheduling decision module 7 according to the safe timing sequence. The timing control module 8 includes a setpoint preloading unit 81, a flexible resource pre-adjustment unit 82, a setpoint input confirmation unit 83, and a switch switching execution unit 84.

[0133] The setting preloading unit 81 is used to preload the target protection setting group to the corresponding protection device according to the coordinated scheduling instruction before the flexible resource pre-adjustment, but it is not put into operation temporarily. The target protection setting group is the protection setting group corresponding to the protection setting group switching instruction in the coordinated scheduling instruction, or the current protection setting group of the corresponding protection device. The setting preloading confirmation time threshold is 10 seconds. If no preloading success status is received from the protection device after 10 seconds, the setting preloading is judged to have failed.

[0134] The flexible resource pre-adjustment unit 82 is connected to the setpoint pre-loading unit 81 and is used to perform at least one of the following flexible resource pre-adjustments before the switch switching: energy storage charging and discharging, distributed power reactive power regulation, charging load adjustment and flexible load response, so that the node power approaches the power flow state under the target topology in advance.

[0135] The setting value activation confirmation unit 83 is connected to the flexible resource pre-adjustment unit 82. It is used to activate and confirm the target protection setting value group after the flexible resource pre-adjustment reaches the preset response condition and before the switch is switched, generating a setting value activation confirmation result. The preset response condition includes the actual response amount of the flexible resource reaching a preset percentage threshold corresponding to the target response amount. In this embodiment, the preset percentage threshold is 90%. If the actual response amount of the flexible resource reaches more than 90% of the target response amount, and the response delay does not exceed 60 seconds, then the flexible resource pre-adjustment is determined to have met the preset response condition. The setting value activation confirmation time threshold is 10 seconds. If the target protection setting value group is not successfully activated within 10 seconds, the setting value activation confirmation result is considered a failure.

[0136] The switch switching execution unit 84 is connected to the setting value input confirmation unit 83 and is used to perform switch switching when the setting value input confirmation result is successful, so as to form the target reconfigured topology. Switch switching may include the switching of sectionalizing switches, tie switches, or circuit breakers. When the setting value input confirmation result is unsuccessful, the switch switching execution unit 84 prohibits the execution of switch switching that would change the fault current path.

[0137] After the target reconfigured topology is formed, the timing control module 8 re-collects node voltages, branch currents, transformer load rates, reverse power flow, and protection device status, and determines whether the actual operating status meets the power flow feasible region and protection selectivity requirements. The post-reconfiguration review time window is 60 seconds. If the node voltages, branch currents, transformer load rates, reverse power flow, and protection selectivity margins all meet the corresponding thresholds within the review time window, the target reconfiguration topology is confirmed to have been successfully executed.

[0138] When a switch fails to operate, a protection setting group switching fails, flexible resource response is insufficient, or the reconfiguration verification fails, the timing control module 8 executes a backup topology or restores to the safe topology. The backup topology prioritizes candidate topologies that have passed the power flow executable verification and protection executable verification; if no available backup topology exists, it restores to the safe topology before reconfiguration.

[0139] Through the timing control module 8, a clear safe execution sequence is formed between the protection setting group switching and the switch action, which can avoid the protection mismatch window caused by the topology having changed but the protection not yet being adapted.

[0140] The feedback update module 9 is used to update the subsequent dynamic reconstruction strategy based on the scheduling execution results. The feedback update module 9 includes an execution result acquisition unit 91, a response deviation calculation unit 92, an envelope update unit 93, a topology filtering update unit 94, a setpoint matching update unit 95, and a scheduling weight update unit 96.

[0141] The execution result acquisition unit 91 is used to acquire protection setting group switching results, flexible resource response results, switch switching results, and power flow status after reconfiguration. Furthermore, the execution result acquisition unit 91 also acquires energy storage response results, distributed power source reactive power response results, charging load response results, flexible load response results, protection verification results, and communication status.

[0142] The response deviation calculation unit 92 is connected to the execution result acquisition unit 91 and is used to calculate the response deviation based on the target response amount corresponding to the coordinated scheduling instruction and the actual response amount corresponding to the flexible resource response result. In this embodiment, when the deviation between the actual response amount and the target response amount is greater than 10%, it is determined that the corresponding flexible resource response is insufficient.

[0143] Envelope update unit 93 is connected to response deviation calculation unit 92 and is used to update the node flexible operation envelope based on the response deviation. When the actual response of a distribution node's flexible resource is lower than 90% of the target response for three consecutive scheduling cycles, the node flexible operation envelope boundary for subsequent scheduling cycles is reduced by 20% of the corresponding resource's rated regulation capacity. When the actual response of a distribution node's flexible resource reaches or exceeds 90% of the target response for three consecutive scheduling cycles, the reliable response weight of the corresponding flexible resource is increased, but the updated node flexible operation envelope does not exceed the corresponding equipment's rated capacity.

[0144] The topology filtering and updating unit 94 is connected to the execution result acquisition unit 91 and is used to update the candidate reconfiguration topology filtering rules based on the switch switching results and the power flow status after reconfiguration. If a certain type of candidate topology repeatedly experiences switch failure, voltage exceeding limits after reconfiguration, or branch overload during actual execution, the priority of this type of candidate topology in subsequent filtering is reduced. If a certain type of candidate topology shows stable reduction in network loss and voltage improvement during actual execution, the priority of this type of candidate topology in subsequent filtering is increased.

[0145] The setting value matching update unit 95 is connected to the execution result acquisition unit 91 and is used to update the protection setting value group matching rules according to the protection setting value group switching results. If a backup protection setting value group experiences a switching failure, protection review failure, or switching risk record during execution, the matching priority of that backup protection setting value group is reduced. If a backup protection setting value group successfully switches three times consecutively and all protection reviews pass, the matching priority of that backup protection setting value group is increased.

[0146] The scheduling weight update unit 96 is connected to the response deviation calculation unit 92 and the execution result acquisition unit 91, respectively, and is used to update the comprehensive scheduling decision weights based on the response deviation and the power flow status after reconfiguration. If the response deviation increases continuously, the weights of the user response cost index and the flexible resource remaining capacity index in the comprehensive evaluation are increased; if the protection safety margin is too small after reconfiguration, the weight of the protection safety margin index in the comprehensive evaluation is increased; if the distributed power generation absorption is significantly improved, the weight of the distributed power generation absorption improvement index is maintained or increased.

[0147] The feedback update module 9 is also used to record situations such as communication anomalies, switch failures, protection setting group switching failures, insufficient energy storage response, charging load refusal to respond, and flexible load recovery anomalies, and uses these anomaly records as subsequent scheduling constraints. The anomaly record retention period is 30 days; within the retention period, switches, protection devices, or flexible resources involved in the anomalies are given lower priority or restricted in use during candidate topology screening, setting group matching, and scheduling decisions.

[0148] Through the feedback update module 9, the node flexible operation envelope, candidate reconstruction topology screening rules, protection setpoint group matching rules, and comprehensive scheduling decision weights can be continuously updated according to the actual execution effect, avoiding the deviation between scheduling results and on-site capabilities caused by long-term use of static models.

[0149] The working principle of this embodiment is as follows: The protection verification module 5 first generates preset fault scenarios for the executable topology of the power flow and calculates the short-circuit current path and protection action time limit under each preset fault scenario. When the protection selectivity margin meets the preset coordination time threshold, the executable topology of the power flow is determined as the executable topology of protection. When the protection selectivity margin does not meet the requirements, the executable topology of the power flow is determined as the topology to be corrected and the mismatched protection device is marked. Subsequently, the matching module 6 searches for backup protection setting groups for the mismatched protection device, filters candidate protection setting groups based on the relationship between the maximum load current, minimum short-circuit current, operating current setting, and operating time limit, and determines the target protection setting group through setting group scoring and protection verification, so that the topology to be corrected of protection is transformed into the executable topology of protection. The scheduling decision module 7 determines the target reconfiguration topology from the executable topology of protection and generates a collaborative scheduling instruction. The timing control module 8 executes the collaborative scheduling instruction in the order of setting preloading, flexible resource pre-adjustment, setting input confirmation, and switch switching. The feedback update module 9 continuously updates the node flexible operation envelope, candidate reconfiguration topology screening rules, protection setting group matching rules, and comprehensive scheduling decision weights based on the execution results.

[0150] Based on the above working principle, this embodiment can use protection selectivity as a mandatory constraint before reconfiguration execution, preventing reconfiguration schemes that are feasible in terms of power flow but not in terms of protection from being implemented in practice; it can transform some protection topologies to be modified into protection executable topologies through backup protection setting group matching, thereby increasing the number of available reconfiguration schemes; it can reduce the risk of protection mismatch windows and power flow impacts through timing control of protection setting group preloading, flexible resource pre-adjustment, protection setting group input confirmation, and switch switching; and it can improve the adaptability and reliability of the system in long-term operation by continuously correcting the envelope, topology screening, setting group matching, and scheduling decision parameters through execution feedback.

[0151] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system, characterized in that, include: The data access module is used to collect topology data, measurement data, adjustable resource operation data, historical response data and protection setting data, and output the operation dataset after verification; The envelope construction module connects to the data access module and is used to generate flexible operational envelopes for each node based on the operational dataset. The topology generation module connects the data access module and the envelope construction module. It is used to generate candidate reconstructed topologies based on the running dataset and to determine the candidate reconstructed topologies whose node prediction power points fall within the corresponding node's flexible running envelope as flexible executable topologies. The power flow projection module connects the topology generation module and the envelope construction module. It is used to perform power flow calculation on the flexible executable topology, and to perform resource correction and / or switch fine-tuning based on the flexible running envelope of the node when the limit is exceeded, and output the power flow executable topology. The protection verification module is connected to the power flow projection module and the data access module. It is used to verify the short-circuit current path and action time of the power flow executable topology based on the protection setting data, and output the protection executable topology or the protection topology to be corrected. The matching module, connected to the protection verification module, is used to match a backup protection setting group for the protection topology to be corrected, and to convert the verified topology into a protection executable topology. The scheduling decision module, which connects the protection verification module and the matching module, is used to determine the target reconstructed topology from the protection executable topology and generate a collaborative scheduling instruction. The timing control module, connected to the scheduling decision module, is used to execute coordinated scheduling instructions in the order of protection setting group preloading, flexible resource pre-adjustment, protection setting group input confirmation, and switch switching.

2. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 1, characterized in that, The envelope construction module includes: The resource ownership identification unit is used to determine the distribution node to which the distributed power source, energy storage device, charging load and flexible load belong based on the operation dataset, and to uniquely assign the same adjustable resource to the distribution node corresponding to its electrical access point within the same scheduling cycle, thereby obtaining the node resource ownership relationship. Adjustable capacity calculation unit, connected to the resource ownership identification unit, is used to calculate the active power up-adjustment capacity, active power down-adjustment capacity, reactive power up-adjustment capacity and reactive power down-adjustment capacity of each distribution node according to the node resource ownership relationship and the adjustable resource operation data, so as to obtain node adjustable capacity data. The envelope boundary generation unit, connected to the adjustable capacity calculation unit, is used to generate the upper boundary of active power, the lower boundary of active power, the upper boundary of reactive power, the lower boundary of reactive power, and the active and reactive capacity coupling constraints of each distribution node based on the node adjustable capacity data, so as to obtain the flexible operation envelope of the node.

3. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 2, characterized in that, The envelope construction module also includes: A trusted response correction unit, connected to the envelope boundary generation unit, is used to correct the node flexible operation envelope based on the historical response data and the execution result of the cooperative scheduling instruction. Specifically, when the historical response success rate of the adjustable resource is lower than a preset trust threshold, the available boundary of the corresponding adjustable resource in the flexible operation envelope of the node is reduced. When the adjustable resource continuously meets the preset trusted response conditions, the trusted response weight of the corresponding adjustable resource is increased, and the corrected node flexible operation envelope does not exceed the rated capacity of the corresponding adjustable resource.

4. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 1, characterized in that, The topology generation module includes: The topology modeling unit is used to build a distribution network topology diagram including distribution nodes, branches and controllable switches based on the running dataset. A switch combination generation unit, connected to the topology modeling unit, is used to generate candidate switch combinations based on the current state of controllable switches in the distribution network topology. The topology constraint judgment unit, connected to the switch combination generation unit, is used to determine the candidate switch combinations that satisfy radial operation constraints, no isolated distribution node constraints, prohibited operation switch constraints, and preset switch action constraints as candidate reconstructed topologies. The node power offset calculation unit, connected to the topology constraint judgment unit, is used to calculate the active power offset and reactive power offset of each distribution node after switching from the current topology to the candidate reconfiguration topology, and to obtain the node predicted power point. The envelope filtering unit, connected to the node power offset calculation unit, is used to determine the candidate reconfigurable topology that falls within the node flexible operation envelope of the corresponding distribution node as the flexible executable topology.

5. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 4, characterized in that, The current projection module includes: A power flow calculation unit is used to receive the flexible executable topology, perform power flow calculation on the flexible executable topology, and obtain the power flow calculation result; The limit-crossing identification unit, connected to the power flow calculation unit, is used to identify the power flow limit-crossing object and the power flow limit-crossing type based on the power flow calculation result; wherein, the power flow limit-crossing object includes at least one of distribution node, branch, transformer and grid connection point, and the power flow limit-crossing type includes at least one of node voltage limit-crossing, branch current limit-crossing, transformer load rate limit-crossing and reverse power flow limit-crossing. The resource correction unit, connected to the limit identification unit, is used to generate a resource correction amount when the power flow limit is exceeded in the flexible executable topology, using the node's flexible operation envelope as the constraint boundary of the resource correction amount. A switch fine-tuning unit, connected to the resource correction unit, is used to generate a switch fine-tuning scheme that does not destroy the radial operation constraints and does not cause the node prediction power point after switch fine-tuning to exceed the node flexible operation envelope of the corresponding distribution node when the resource correction amount cannot eliminate the power flow over-limit. The projection iteration unit, connected to the resource correction unit, the switch fine-tuning unit, and the power flow calculation unit, is used to adjust the corresponding adjustable resources according to the resource correction amount and / or adjust the corresponding controllable switches according to the switch fine-tuning scheme, and then re-trigger power flow calculation until the node voltage, branch current, transformer load rate, and reverse power flow of the topology after resource correction and / or switch fine-tuning meet the corresponding preset safety thresholds, and then determine it as the power flow executable topology.

6. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 5, characterized in that, The resource correction unit includes: The over-limit type assignment subunit is used to assign each power flow over-limit object to a voltage over-limit category, voltage over-limit category, overload category, or reverse power flow category according to a preset priority. The same power flow over-limit object is assigned to only one category in the same iteration round. The overload category includes branch current over-limit category and / or transformer load rate over-limit category. The voltage limit exceedance correction subunit is connected to the limit exceedance type dispatch subunit and is used to generate at least one resource correction amount among distributed power source reactive power absorption, energy storage charging and distributed power source limited generation when the power flow limit exceedance object belongs to the voltage limit exceedance category. The voltage lower limit correction subunit is connected to the over-limit type dispatch subunit and is used to generate at least one resource correction amount among energy storage discharge, distributed power source reactive power support and charging load derating when the power flow over-limit object belongs to the voltage lower limit category. The overload correction subunit, connected to the over-limit type dispatch subunit, is used to generate at least one resource correction amount among charging load adjustment, flexible load response and energy storage discharge when the power flow over-limit object belongs to the overload category. The reverse power flow correction subunit, connected to the over-limit type dispatch subunit, is used to generate at least one resource correction amount among energy storage charging, charging load increasing acceptance power, flexible load response, and distributed power generation limitation when the power flow over-limit object belongs to the reverse power flow category.

7. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 1, characterized in that, The protection verification module includes: The fault scenario generation unit is used to generate preset fault scenarios based on the power flow executable topology. A short-circuit current calculation unit, connected to the fault scenario generation unit, is used to calculate the short-circuit current under each preset fault scenario and obtain short-circuit current data. The fault path identification unit is connected to the short-circuit current calculation unit and is used to identify the protection devices through which the short-circuit current flows and the relationship between the upper and lower level protections based on the short-circuit current data and the protection setting data, so as to obtain the fault current path data. An action time limit calculation unit is connected to the fault path identification unit and is used to calculate the action time limit of each protection device based on the fault current path data and the protection setting data. The protection selectivity judgment unit is connected to the action time limit calculation unit. It is used to determine whether the power flow executable topology meets the protection selectivity requirements based on the action time limits of the upper and lower level protection devices and the preset coordination time threshold. When the protection selectivity requirements are met, the protection executable topology is output. When the protection selectivity requirements are not met, the protection topology to be corrected is output and the corresponding mismatch protection device is marked.

8. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 7, characterized in that, The matching module includes: The setting group retrieval unit is used to retrieve a spare protection setting group from the protection setting data according to the mismatch protection device corresponding to the protection topology to be corrected. The operating current adaptation unit, connected to the setting group retrieval unit, is used to filter candidate protection setting groups from the standby protection setting group based on the maximum load current determined by the operating dataset under the protection topology to be corrected, and the minimum short-circuit current determined by the short-circuit current data; wherein the operating current setting of the candidate protection setting group is greater than the maximum load current and less than the minimum short-circuit current. An operating time limit adaptation unit, connected to the operating current adaptation unit, is used to calculate the operating time limits of the upper and lower level protection devices based on the candidate protection setting groups, and to screen candidate protection setting groups that meet the protection selectivity requirements. The protection verification unit is connected to the action time limit adaptation unit. It is used to re-verify the short-circuit current path and action time limit of each of the screened candidate protection setting groups, and to determine the candidate protection setting groups that pass the verification as usable protection setting groups. The matching output unit is connected to the protection verification unit and is used to determine the target protection setting group from the available protection setting groups according to the preset value group selection rules, convert the protection topology to be corrected into the protection executable topology, and output the protection executable topology and the protection setting group switching instruction corresponding to the target protection setting group.

9. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 1, characterized in that, The timing control module includes: The setting preloading unit is used to preload the target protection setting group to the corresponding protection device according to the coordinated scheduling instruction before the flexible resource pre-adjustment. The target protection setting group is the protection setting group corresponding to the protection setting group switching instruction in the coordinated scheduling instruction, or the current protection setting group of the corresponding protection device. The flexible resource pre-adjustment unit, connected to the setpoint pre-loading unit, is used to perform at least one of the following flexible resource pre-adjustments before switching: energy storage charging and discharging, distributed power reactive power regulation, charging load adjustment, and flexible load response. A setpoint input confirmation unit, connected to the flexible resource pre-adjustment unit, is used to input and confirm the target protection setpoint group after the flexible resource pre-adjustment reaches the preset response condition and before the switch is switched, and generate a setpoint input confirmation result; wherein, the preset response condition includes the actual response amount of the flexible resource reaching the preset ratio threshold corresponding to the target response amount. A switch switching execution unit is connected to the setpoint input confirmation unit and is used to perform switch switching when the setpoint input confirmation result is successful, so as to form the target reconstructed topology; When the confirmation result of the set value input is a failure, the switch switching execution unit shall prohibit the execution of switch switching that would change the fault current path.

10. The distribution network dynamic reconfiguration and optimized dispatching system for a new type of power system according to claim 1, characterized in that, It also includes a feedback update module, which is connected to the timing control module, and is used to update the node flexible operation envelope, candidate reconstruction topology screening rules, protection setting group matching rules and comprehensive scheduling decision weights based on the execution results of the collaborative scheduling instructions; The feedback update module includes: The execution result acquisition unit is used to acquire protection setting group switching results, flexible resource response results, switch switching results, and power flow status after reconfiguration. A response deviation calculation unit, connected to the execution result acquisition unit, is used to calculate the response deviation based on the target response amount corresponding to the collaborative scheduling instruction and the actual response amount corresponding to the flexible resource response result. An envelope update unit, connected to the response deviation calculation unit, is used to update the node's flexible operation envelope based on the response deviation. A topology filtering and updating unit, connected to the execution result acquisition unit, is used to update the candidate reconstruction topology filtering rules according to the switch switching result and the power flow state after reconstruction. A setting value matching and updating unit, connected to the execution result acquisition unit, is used to update the protection setting value group matching rule according to the protection setting value group switching result; The scheduling weight update unit is connected to the response deviation calculation unit and the execution result acquisition unit, respectively, and is used to update the comprehensive scheduling decision weight according to the response deviation and the reconstructed power flow state.

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