Active power distribution network voltage sag suppression configuration method, system, device and medium

Abstract

The present application relates to the technical field of power distribution network, and more particularly to a kind of active power distribution network voltage sag suppression configuration method, system, equipment and medium.The method obtains active power distribution network operation data and a variety of voltage sag scene data, first constructs sag risk portrait in combination with the voltage sag characteristics of each node in different scenarios and node guarantee demand, then determines recovery influence domain according to the scenario-based voltage recovery effect of dynamic voltage restorer when it is set at different candidate access bus positions, on the basis of which, sag risk portrait and recovery influence domain are jointly used for joint optimization of dynamic voltage restorer access bus position and configuration capacity, and the configuration results that do not achieve recovery target are iteratively corrected through multi-scenario recovery check, so as to more accurately determine the access position and configuration capacity of dynamic voltage restorer.

Description

Technical Field

[0001] This invention relates to the field of power distribution network technology, and in particular to a method, system, device and medium for active power distribution network voltage sag suppression configuration. Background Technology

[0002] With the increasing integration of distributed photovoltaic (PV), energy storage, and power electronic loads into distribution networks, traditional passive distribution networks are gradually transforming into active distribution networks. Distributed power sources alter the power flow direction, node voltage distribution, and fault disturbance propagation paths of the distribution network, making the impact of voltage sags highly scenario-dependent, location-dependent, and load-dependent. Voltage sags are typically caused by short-circuit faults, large-capacity motor startup, transformer switching, and rapid switching operations, and may lead to tripping or production interruptions in sensitive user equipment such as semiconductor manufacturing, precision machining, data centers, and rail transit traction auxiliary systems.

[0003] Dynamic Voltage Restorers (DVRs) inject compensation voltage in series to quickly restore load-side voltage during voltage sag events, making them crucial devices in voltage sag mitigation. For radial or weak-loop distribution systems, the installation location of a single DVR not only affects the restoration effect on its connected bus but also the voltage recovery magnitude at downstream or adjacent nodes. Therefore, determining the DVR installation bus and capacity within limited investment and capacity constraints is a key issue in active distribution network voltage sag mitigation.

[0004] In existing technologies, some methods first partition the network based on indicators such as electrical distance, sensitivity, or swing radius, and then select the DVR installation location within each partition. While this approach is effective in reducing control scale, it is prone to the following problems when used for voltage sag mitigation: the partition boundaries may not coincide with the sag propagation influence domain; nodes within the same partition may have different sag risks and compensation capacity requirements; the partitioning results are sensitive to indicator thresholds, sorting benchmarks, or smoothing parameters; and existing partitions may need to be readjusted when photovoltaic output and fault location change. Therefore, existing technologies struggle to accurately determine the installation bus and configuration capacity of dynamic voltage restorers. Summary of the Invention

[0005] In view of this, in order to solve the above-mentioned technical problems, the present invention provides an active distribution network voltage sag suppression configuration method, system, device and medium.

[0006] The first aspect of this invention provides a method for configuring active distribution network voltage sag suppression, the method comprising: Acquire operational data of the target active distribution network and scenario data corresponding to multiple voltage sag scenarios; Based on the scenario data, determine the voltage sag characteristics of each node under the multiple voltage sag scenarios, and construct a voltage sag risk profile for each node based on the voltage sag characteristics and the node assurance requirements of each node. Based on the operational data and the scenario data, determine the voltage recovery effect of the dynamic voltage restorer on each node under the multiple voltage sag scenarios when it is set at each preset candidate access bus position, and determine the recovery influence domain corresponding to each candidate access bus position based on the voltage recovery effect. Based on the transient risk profile of each node and the recovery influence domain corresponding to each candidate access bus location, the access bus location and configuration capacity of the target dynamic voltage restorer are jointly optimized under preset configuration constraints to obtain an initial configuration scheme. The voltage recovery results of each node under the multiple voltage sag scenarios are verified according to the initial configuration scheme. Based on the voltage recovery results that do not meet the preset recovery target, the initial configuration scheme is iteratively corrected to obtain the target configuration scheme of the target dynamic voltage restorer.

[0007] In one example, the process involves determining the voltage sag characteristics of each node under the multiple voltage sag scenarios based on the scenario data, and constructing a voltage sag risk profile for each node based on the voltage sag characteristics and the node assurance requirements of each node, including: Based on the difference between the preset governance threshold and the voltage sag of each node in each voltage sag scenario, the voltage sag amplitude gap of each node in each voltage sag scenario is determined. Based on the voltage sag amplitude gap, voltage sag duration, and scenario occurrence probability of each node, determine the scenario sag risk of each node under each voltage sag scenario; Based on at least one of the load type, user level, and power supply priority corresponding to each node, the load importance corresponding to each node is determined, and the scenario sag risk of each node is weighted and aggregated according to the load importance to obtain the basic sag risk corresponding to each node. Based on the node voltage of each node under the baseline operating state and the node voltage before the voltage dip under the distributed photovoltaic access state, the steady-state support correction result for each node is determined. Based on the steady-state support correction results, the temporary drop risk is corrected to obtain the temporary drop risk profile for each node.

[0008] In one example, determining the steady-state support correction result for each node based on the node voltage under the baseline operating state and the node voltage before the voltage dip under distributed photovoltaic access state includes: Obtain the operating parameters of the distributed photovoltaic system, determine the active power output and reactive power adjustment range of the distributed photovoltaic system based on the operating parameters, and determine the distribution network operation point under the distributed photovoltaic system access state based on the active power output and the reactive power adjustment range. Based on the power flow calculation of the distribution network operating point, the node voltage before the sag of each node under the distributed photovoltaic access state is obtained; The voltage support amount of the node voltage before the voltage sag is determined relative to the node voltage of the corresponding node under the reference operating state, and the steady-state support correction result is determined based on the voltage support amount; wherein, the steady-state support correction result characterizes the degree of steady-state voltage support provided by distributed photovoltaic to the corresponding node before the voltage sag occurs.

[0009] In one example, determining the voltage recovery effect of the dynamic voltage restorer at each of the candidate access bus locations based on the operational data and the scenario data, under the multiple voltage sag scenarios, and determining the recovery influence domain corresponding to each of the candidate access bus locations based on the voltage recovery effect, includes: For each of the candidate access bus locations, a preset compensation effect is applied to the corresponding candidate access bus location under each of the voltage sag scenarios; Based on the operational data, the node voltage increment generated by the preset compensation effect transmitted from the corresponding candidate access bus position to each node is determined, so as to obtain the voltage recovery effect of the corresponding candidate access bus position on each node in each voltage sag scenario. Based on the node voltage increment and the voltage sag of each node in the corresponding voltage sag scenario, determine the compensated voltage of each node; Establish a recovery coverage relationship for candidate access bus locations, nodes, and voltage sag scenarios where the compensated voltage reaches the preset recovery target, and determine the recovery influence domain corresponding to each candidate access bus location based on the recovery coverage relationship.

[0010] In one example, the method further includes, prior to joint optimization of the access bus location and configuration capacity of the target dynamic voltage restorer: Based on the voltage sag risk profile corresponding to each node, the probability of occurrence of each voltage sag scenario, and the recovery impact domain corresponding to each candidate access bus location, the risk coverage benefit corresponding to each candidate access bus location is determined. Based on the configuration capacity required for the nodes within the corresponding recovery influence domain to reach the preset recovery target according to the location of each candidate access bus, the capacity requirement corresponding to each candidate access bus location is determined. The risk coverage benefits, capacity requirements, and configuration costs corresponding to each of the candidate access bus locations are compared to determine the dominance relationship between the candidate access bus locations. Candidate access bus locations that are dominated by other candidate access bus locations in terms of risk coverage benefits, capacity requirements, and configuration costs are removed to obtain a set of effective candidate access bus locations, and the joint optimization is performed based on the set of effective candidate access bus locations.

[0011] In one example, based on the transient risk profile of each node and the recovery influence domain corresponding to each candidate access bus location, and under preset configuration constraints, the access bus location and configuration capacity of the target dynamic voltage restorer are jointly optimized to obtain an initial configuration scheme, including: Based on the voltage sag risk profile corresponding to each node and the probability of occurrence of each voltage sag scenario, the uncovered risk corresponding to the uncovered risk variable is determined; The capacity configuration cost of the dynamic voltage restorer is determined based on the configuration capacity and unit capacity cost corresponding to each of the candidate access bus locations. The redundancy coverage cost is determined based on the degree of overlap of the recovery influence domains of multiple configured dynamic voltage restorers on the same node in the same voltage sag scenario. A joint optimization model for coverage and capacity is established with the joint optimization objectives of reducing the risk of uncovering, the cost of capacity configuration, and the cost of redundant coverage. Based on the preset configuration constraints, the coverage-capacity joint optimization model is solved to determine the access bus position of the dynamic voltage restorer from multiple candidate access bus positions, and to determine the configuration capacity corresponding to the access bus position, thereby obtaining the initial configuration scheme; wherein, the preset configuration constraints include node scenario coverage constraints, candidate access bus position capacity constraints, and configuration budget constraints.

[0012] In one example, the voltage recovery results of each node under multiple voltage sag scenarios are verified according to the initial configuration scheme, and the initial configuration scheme is iteratively corrected based on the voltage recovery results that do not meet the preset recovery target to obtain the target configuration scheme of the target dynamic voltage restorer, including: Based on the access bus location and configuration capacity in the initial configuration scheme, the compensated voltage of each node in each voltage sag scenario is determined, and the compensated voltage is compared with the preset recovery target to determine the nodes that have not reached the preset recovery target and the corresponding voltage sag scenarios. Based on the nodes that have not reached the preset recovery target and the corresponding voltage sag scenarios, an uncovered risk constraint is generated, and the uncovered risk constraint is added to the optimization model corresponding to the joint optimization. When the configured capacity of the selected access bus location does not reach the corresponding capacity limit, the configured capacity of the selected access bus location is adjusted based on the uncovered risk constraint. If there are still nodes that do not reach the preset recovery target after adjusting the configured capacity, the substitute access bus location is determined according to the uncovered risk reduction amount and the newly added configured capacity corresponding to each candidate access bus location. The initial configuration scheme is updated based on the adjusted configuration capacity and / or the location of the substitute access bus. The voltage recovery results of each node under the multiple voltage sag scenarios are re-verified based on the updated configuration scheme until the compensated voltage of each node reaches the preset recovery target, or the configuration capacity and / or configuration cost reaches the constraint boundary corresponding to the preset configuration constraint. The configuration scheme at the end of the iteration is then determined as the target configuration scheme.

[0013] Secondly, the present invention also provides an active distribution network voltage sag suppression configuration system, the system comprising: The data acquisition module is used to acquire the operation data of the target active distribution network and the scenario data corresponding to multiple voltage sag scenarios; The profile building module is used to determine the voltage sag characteristics of each node under the multiple voltage sag scenarios based on the scenario data, and to build a sag risk profile for each node based on the voltage sag characteristics and the node assurance requirements of each node. The influence domain determination module is used to determine the voltage recovery effect of the dynamic voltage restorer on each node under the multiple voltage sag scenarios when it is set at each preset candidate access bus position, based on the running data and the scenario data, and to determine the recovery influence domain corresponding to each candidate access bus position based on the voltage recovery effect. The initial configuration determination module is used to jointly optimize the access bus position and configuration capacity of the target dynamic voltage restorer under preset configuration constraints, based on the temporary descent risk profile of each node and the recovery influence domain corresponding to each candidate access bus position, to obtain an initial configuration scheme. The target configuration determination module is used to verify the voltage recovery results of each node under the multiple voltage sag scenarios according to the initial configuration scheme, and to iteratively correct the initial configuration scheme according to the voltage recovery results that do not reach the preset recovery target, so as to obtain the target configuration scheme of the target dynamic voltage restorer.

[0014] Thirdly, the present invention also provides an electronic device, the electronic device including a memory and a processor, the memory storing a computer program, the computer program being executed by the processor causing the processor to perform the steps of the active distribution network voltage sag suppression configuration method as described in the first aspect.

[0015] Fourthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the steps of the active distribution network voltage sag suppression configuration method as described in the first aspect.

[0016] As can be seen from the above technical solutions, this invention acquires active distribution network operation data and various voltage sag scenario data. First, it constructs a voltage sag risk profile by combining the voltage sag characteristics of each node under different scenarios and the node's guarantee requirements to identify the actual governance priorities of different nodes. Then, it determines the recovery influence domain based on the scenario-based voltage recovery effect of the dynamic voltage restorer when it is set at different candidate access bus positions. This makes the device configuration no longer dependent solely on fixed network partitions or bus electrical positions, but can reflect the real recovery capability of candidate access positions under different fault locations, sag degrees, and operating states. On this basis, the sag risk profile and the recovery influence domain are used together for joint optimization of the dynamic voltage restorer access bus position and configuration capacity. Finally, it iterative corrections are made to configuration results that do not achieve the recovery target through multi-scenario recovery verification. This enables a continuous correspondence between the target of dynamic voltage restorer, its actual scope of action, and its capacity deployment. Under limited capacity and configuration conditions, priority is given to ensuring nodes with higher sag risk or stronger demand. This reduces coverage blind spots, invalid site selection, and capacity redundancy caused by inconsistencies between pre-zoned areas and sag propagation ranges. It also improves the adaptability of the configuration scheme to changes in fault location, sag scenarios, and active distribution network operating status, thereby more accurately determining the access location and configuration capacity of the dynamic voltage restorer. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an application environment diagram of an active distribution network voltage sag suppression configuration method provided by an embodiment of the present invention; Figure 2 A flowchart of an active distribution network voltage sag suppression configuration method provided by an embodiment of the present invention; Figure 3 This is a schematic diagram of an active distribution network voltage sag suppression configuration system provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

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

[0020] The active distribution network voltage sag suppression configuration method provided in this application embodiment can be applied to, for example, Figure 1 The application environment shown is illustrated. Terminal 101 communicates with server 102 via a network. A data storage system can store the data that server 102 needs to process. The data storage system can be integrated onto server 102, or it can be located in the cloud or on another network server. Terminal 101 or server 102 executes an active distribution network voltage sag suppression configuration method, which includes: acquiring the operation data of the target active distribution network and scenario data corresponding to multiple voltage sag scenarios; determining the voltage sag characteristics of each node under multiple voltage sag scenarios based on the scenario data, and constructing a voltage sag risk profile for each node based on the voltage sag characteristics and the node guarantee requirements of each node; determining the voltage recovery effect of the dynamic voltage restorer on each node under multiple voltage sag scenarios when it is set at each preset candidate access bus position based on the operation data and scenario data, and determining the recovery influence domain corresponding to each candidate access bus position based on the voltage recovery effect; jointly optimizing the access bus position and configuration capacity of the target dynamic voltage restorer under preset configuration constraints based on the voltage sag risk profile of each node and the recovery influence domain corresponding to each candidate access bus position to obtain an initial configuration scheme; verifying the voltage recovery results of each node under multiple voltage sag scenarios based on the initial configuration scheme, and iteratively correcting the initial configuration scheme based on the voltage recovery results that do not reach the preset recovery target to obtain the target configuration scheme of the target dynamic voltage restorer.

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

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

[0023] The target active distribution network can be a medium- or low-voltage distribution network containing distributed photovoltaic, distributed energy storage, power electronic loads, and traditional spinning loads. The target active distribution network can adopt a radial, weakly looped, or reconfigurable network structure formed by interconnecting switches. Nodes can correspond to distribution buses, load connection points, distributed power source grid connection points, or sensitive user connection points requiring voltage sag protection.

[0024] like Figure 2 As shown, this application provides a method for configuring active distribution network voltage sag suppression, which is applied to... Figure 1 Taking terminal 101 or server 102 as an example, the explanation includes the following steps S1 to S5. Wherein: Step S1: Obtain the operation data of the target active distribution network and the scenario data corresponding to multiple voltage sag scenarios.

[0025] The operational data is a set of data that characterizes the network connectivity, normal operating status, voltage response capability, and distributed photovoltaic (PV) operating boundaries of the target active distribution network. For example, the operational data may include the distribution network topology, branch impedance, node admittance matrix, node impedance matrix, node reference voltage, voltage amplitude sensitivity matrix, distributed PV access locations, active power output range, reactive power regulation range, maximum allowable configuration capacity of candidate access buses, and unit capacity cost.

[0026] Scenario data is a dataset that can characterize the voltage sag state of nodes under different disturbance conditions. Each voltage sag scenario can be determined by the fault location, fault type, operating status before the disturbance, sag duration, and photovoltaic output status. Its scenario data can include the sag voltage, sag duration, and scenario occurrence probability of each node.

[0027] The topology is represented as G=(N,E), where N is the set of nodes and E is the set of branches. Branch parameters retain the branch's start and end nodes, line length l, unit resistance r, unit reactance x, and ground susceptance b, used to form the branch admittance and node admittance matrices Y. bus and node impedance matrix Z bus It also provides the network foundation for power flow calculation, short-circuit calculation, and voltage recovery transfer coefficient calculation. Among them:

[0028] This formula represents the standard form of the nodal admittance matrix, which is a complex square matrix of the same order as the number of nodes n in the distribution network. The diagonal elements of the matrix represent the nodal self-admittance, and the off-diagonal elements represent the nodal mutual admittance. It fully describes the electrical connection relationships between the nodes in the distribution network and is the core foundational matrix for subsequent power flow calculations and sag analysis.

[0029]

[0030] This formula is for calculating the series admittance of a branch. Where r ij x ij These are the total resistance and total reactance of branch ij, respectively.

[0031]

[0032] This formula is the method for calculating nodal self-admittance.

[0033]

[0034] This formula is the definition of nodal mutual admittance.

[0035] The nodal impedance matrix can be expressed as:

[0036] The node impedance matrix is ​​used to characterize the relationship between changes in node injected current and changes in node voltage, and can provide a basis for short-circuit calculations and calculations of the voltage recovery transmission relationship from candidate access buses to controlled nodes.

[0037] The formation of the aforementioned network matrix allows subsequent calculations of voltage sag scenarios and recovery effects to be based on the same distribution network electrical model, avoiding deviations that occur when using simple topological distance to represent the effective range of the dynamic voltage restorer.

[0038] Node reference voltage V i 0 Obtained through normal operating power flow calculations, it is usually expressed as a per-unit value. Unless otherwise specified, the normal operating voltage constraint for the distribution network can be taken as 0.95 pu ≤ V. i 0 ≤1.05 pu.

[0039] Voltage amplitude sensitivity matrix S P and S Q These represent the response of node voltage amplitudes to changes in active and reactive power injection at each bus. The voltage amplitude sensitivity matrix can be obtained by inverting the power flow Jacobian matrix or determined using a perturbation power flow method. For example, a preset small change in active or reactive power is applied to bus c, the power flow calculation is re-performed, and the corresponding sensitivity is determined based on the ratio of the change in voltage amplitude to the change in power at each node.

[0040] Node sag voltage V iω The duration of the transient sag is obtained from short-circuit calculation, electromagnetic transient simulation, and dynamic power flow simulation; tsag duration. ω Determined by protection clearing time, reclosing time, fault duration statistics, or simulation duration; scenario probability p ωIt can be calculated based on line or equipment failure rate, historical occurrence frequency, or Monte Carlo sample frequency.

[0041] Step S2: Based on the scenario data, determine the voltage sag characteristics of each node under multiple voltage sag scenarios, and construct a voltage sag risk profile for each node based on the voltage sag characteristics and the node assurance requirements of each node.

[0042] The voltage sag scenario set Ω={ω} is generated from historical power quality monitoring records, protection action records, equipment failure rate statistics, short circuit calculations, electromagnetic transient simulations, or Monte Carlo sampling. Each scenario ω includes the fault location l. ω Fault type g ω Node sag voltage V iω Duration of temporary descent t ω and scenario probability p ω The fault location can be determined by feeder number, line section, and distance from the starting point; fault types include single-phase ground fault, two-phase short circuit, two-phase ground fault, and three-phase short circuit, and can also be expanded to include high-capacity motor starting, transformer inrush current, and transients caused by switch switching. Among these, fault location l ω and fault type g ω Used to simulate and generate node sag voltage V iω Scenario probability p ω and the scenario-related voltage recovery transfer coefficient H i,cω ; Node sag voltage V iω Duration of temporary descent t ω and scenario probability p ω Directly proceed to node risk profiling, coverage assessment, and rolling verification.

[0043] Voltage sag characteristics include at least the sag magnitude gap and sag duration of a node under various voltage sag scenarios. Node assurance requirements characterize the degree to which a corresponding node needs to be prioritized for restoration when a voltage sag occurs, and can be determined based on at least one of node load type, user level, power supply priority, and load sensitivity.

[0044] The voltage sag risk profile is not a single static voltage indicator of a node, but a comprehensive characterization of the severity, probability, duration, load importance, and steady-state support status of a node before a voltage sag in multiple voltage sag scenarios.

[0045] Step S3: Based on the running data and scenario data, determine the voltage recovery effect of the dynamic voltage restorer on each node under multiple voltage sag scenarios when it is set at each preset candidate access bus position, and determine the recovery influence domain corresponding to each candidate access bus position based on the voltage recovery effect.

[0046] The locations of candidate access buses can be pre-determined based on the feasibility of the project installation and the effectiveness of the mitigation measures, forming a candidate access bus set C. Feasibility of the project installation can include whether there are conditions for series connection of dynamic voltage restorers, whether there is space for equipment installation and maintenance, whether there are metering and protection interfaces, and whether there are communication capabilities. Effectiveness of the mitigation measures can include whether the corresponding bus is located upstream of a sensitive load, the importance of the downstream load of the corresponding bus, and the voltage recovery transmission capability of the bus to other nodes.

[0047] For candidate access bus location c, its maximum allowable configuration capacity can be denoted as S. cmax The maximum allowable configuration capacity can be determined based on at least one of the following: bus short-circuit capacity, transformer remaining capacity, feeder rated capacity, equipment installation space, and dynamic voltage restorer product capacity class.

[0048] The unit capacity cost of candidate access bus location c is denoted as k. c It can include the converted value of the dynamic voltage restorer equipment cost, civil engineering installation cost, wiring modification cost, and the total life cycle operation and maintenance cost.

[0049] By determining the location, capacity limit, and unit capacity cost of candidate access buses before scenario calculation, the subsequent joint optimization output can be made engineering feasible, rather than just outputting the theoretically optimal node.

[0050] Voltage recovery refers to the voltage recovery amplitude generated when a dynamic voltage restorer, installed at a candidate access bus location, injects compensation voltage that is transmitted to each node via the target active distribution network. Because the fault location, fault type, photovoltaic output, and network operating point differ under different voltage sag scenarios, the recovery effect of the same candidate access bus location on the same node can also vary.

[0051] Therefore, the recovery impact domain is not defined solely by the downstream or electrically adjacent nodes of the candidate access bus location, but rather by the actual recovery coverage relationship between the candidate access bus location, the controlled node, and the voltage sag scenario.

[0052] Step S4: Based on the transient risk profile of each node and the recovery influence domain corresponding to each candidate access bus location, under the preset configuration constraints, jointly optimize the access bus location and configuration capacity of the target dynamic voltage restorer to obtain the initial configuration scheme.

[0053] Joint optimization is used to coordinate node risk protection requirements, the recovery range of dynamic voltage restorers, the upper limit of candidate access bus capacity, and the configuration budget. The initial configuration scheme includes at least the selected dynamic voltage restorer access bus locations and the corresponding configuration capacity for each access bus location.

[0054] Step S5: Verify the voltage recovery results of each node under multiple voltage sag scenarios according to the initial configuration scheme, and iteratively correct the initial configuration scheme based on the voltage recovery results that do not meet the preset recovery target to obtain the target configuration scheme of the target dynamic voltage restorer.

[0055] The recovery verification can employ electromagnetic transient simulation or dynamic power flow calculation with higher accuracy than the influence domain estimation process in step S3. Specifically, the location of the dynamic voltage restorer connected to the bus, its configuration capacity, injected voltage control parameters, and capacity limits determined in the initial configuration scheme are set in the target active distribution network simulation model, and each voltage sag scenario is loaded. Subsequently, through...

[0056] The simulation yields the actual voltage dips of each node under the initial configuration. The actual voltage dips of each node in each voltage dip scenario are then compared to the preset recovery target. If all nodes meet the recovery target in all voltage dip scenarios, the initial configuration is directly determined as the target configuration. If there are nodes and corresponding scenarios that do not meet the recovery target, the connection location and corresponding capacity of the dynamic voltage restorer are adjusted to generate a corrected configuration. This verification process is repeated until all nodes meet the recovery target in all scenarios, and finally, the target configuration that satisfies the constraints is output.

[0057] It should be noted that this application first constructs a voltage sag risk profile by acquiring active distribution network operation data and various voltage sag scenario data, combining the voltage sag characteristics of each node under different scenarios and the node guarantee requirements, in order to identify the actual governance priority of different nodes; then, based on the scenario-based voltage recovery effect of the dynamic voltage restorer on each node when it is set at different candidate access bus positions, the recovery influence domain is determined, so that the device configuration no longer depends solely on fixed network partitions or bus electrical positions, but can reflect the real recovery capability of the candidate access position under different fault locations, sag degrees, and operating states; on this basis, the voltage sag risk profile and the recovery influence domain are used together for joint optimization of the dynamic voltage restorer access bus position and configuration capacity, and the configuration results that do not achieve the recovery target are iteratively corrected through multi-scenario recovery verification. This enables a continuous correspondence between the target of dynamic voltage restorer, its actual scope of action, and its capacity deployment. Under limited capacity and configuration conditions, priority is given to ensuring nodes with higher sag risk or stronger demand. This reduces coverage blind spots, invalid site selection, and capacity redundancy caused by inconsistencies between pre-zoned areas and sag propagation ranges. It also improves the adaptability of the configuration scheme to changes in fault location, sag scenarios, and active distribution network operating status, thereby more accurately determining the access location and configuration capacity of the dynamic voltage restorer.

[0058] In some embodiments, based on scenario data, the voltage sag characteristics of each node under multiple voltage sag scenarios are determined, and a sag risk profile corresponding to each node is constructed based on the voltage sag characteristics and the node assurance requirements of each node. This includes: determining the sag amplitude gap of each node under each voltage sag scenario based on the difference between a preset governance threshold and the sag voltage of each node under each voltage sag scenario; determining the scenario sag risk of each node under each voltage sag scenario based on the sag amplitude gap, sag duration, and scenario occurrence probability of each node; determining the load importance of each node based on at least one of the load type, user level, and power supply priority of each node, and weighting and aggregating the scenario sag risks of each node based on the load importance to obtain the basic sag risk of each node; determining the steady-state support correction result of each node based on the node voltage under the baseline operating state and the node voltage before sag under the distributed photovoltaic access state; and correcting the basic sag risk based on the steady-state support correction result to obtain the sag risk profile of each node.

[0059] Among them, the preset governance threshold V th Used to determine if a node is experiencing a voltage sag that requires mitigation. When the node sag voltage is below V... th At this point, it is considered that the node has a voltage sag mitigation requirement. Assume there are N nodes in the active distribution network. For node i, under scenario ω, define the mitigation threshold and the voltage sag. The gap in the temporary decrease can be expressed as:

[0060] In the formula, This represents the voltage sag gap. By only metering the voltage portion below the mitigation threshold, normal voltage fluctuations can be avoided from being included in the sag risk calculation.

[0061] The scenario sagging risk of node i in scenario ω can be determined based on the sagging amplitude gap, sagging duration, and scenario occurrence probability. For example, the scenario sagging risk can be... Represented as:

[0062] in, Let ω be the probability of scenario ω occurring. This refers to the duration of the temporary descent in this scenario. This serves as a reference value for the duration of the temporary drop, used to normalize the duration. This is used to make the duration of a temporary stop dimensionless. The higher the probability of the scenario occurring, the larger the gap in the magnitude of the temporary stop, or the longer the duration of the temporary stop, the greater the risk of a temporary stop.

[0063] If the duration varies greatly across different scenarios, an upper limit can be set for the duration item without changing its physical meaning, in order to avoid the very few scenarios with abnormal durations having an excessive impact on the risk outcome.

[0064] Subsequently, the load importance of each node is determined by at least one of the load type, user level, and power supply priority corresponding to each node, so as to assign higher weight to sensitive or critical load nodes. For example, the load importance w i Integer values ​​within the range [1, 10] can be used, with smaller values ​​for general residential load nodes and larger values ​​for primary important user nodes. For loads sensitive to voltage sags, such as semiconductor manufacturing production lines, data centers, or rail transit auxiliary systems, a higher load importance weight can be set; for ordinary loads with strong tolerance to short-term voltage changes, a relatively lower load importance weight can be set.

[0065] Then, considering the duration of the temporary stop, the probability of the scenario, and the importance of the node, the basic risk Ri of the node temporary stop is constructed: .

[0066] Then, based on the node voltages of each node under the baseline operating state and the node voltages before voltage sags under distributed photovoltaic (PV) integration, the steady-state support correction results for each node are determined. Specifically, determining the steady-state support correction results for each node based on the node voltages of each node under the baseline operating state and the node voltages before voltage sags under distributed PV integration includes: obtaining distributed PV operating parameters; determining the active power output and reactive power regulation range of distributed PV based on the distributed PV operating parameters; determining the distribution network operating point under distributed PV integration based on the active power output and reactive power regulation range; performing power flow calculations based on the distribution network operating point to obtain the node voltages before voltage sags under distributed PV integration; determining the voltage support amount of the node voltage before voltage sag relative to the node voltage of the corresponding node under the baseline operating state; and determining the steady-state support correction results based on the voltage support amount. The steady-state support correction results characterize the degree of steady-state voltage support provided by distributed PV to the corresponding node before a voltage sag occurs.

[0067] The operating parameters of distributed photovoltaic (PV) systems can be obtained from PV power prediction systems, PV inverter monitoring systems, or historical operating databases. When determining the operating point of the distribution network under distributed PV access conditions, a typical PV output point can be selected, or low-output, medium-output, and high-output operating points can be selected separately for calculation.

[0068] Under any selected active power output, the inverter's reactive power output should satisfy the reactive power regulation boundary shown in the following formula. Based on the photovoltaic active power output, reactive power output, load power at each node, and network operation mode, the power flow calculation input is used to obtain the distribution network operating point under distributed photovoltaic access conditions. Wherein, the photovoltaic active power output range [P]... pv,min ,P pv,max The reactive power boundary of the inverter can be determined by the day-ahead forecast, historical quantiles, or typical daily curves; the reactive power boundary of the inverter is determined by the apparent capacity constraint.

[0069]

[0070] In the formula, , These are the minimum and maximum permissible reactive power output of photovoltaic systems. , These are the minimum and maximum permissible active power outputs for photovoltaic power, respectively. Q contributes to photovoltaic power. pv For the actual reactive power output of photovoltaics; S inv This is the rated apparent capacity of the inverter.

[0071] Power flow calculations can employ forward-backward substitution, the Newton-Raphson method, or other power flow calculation methods suitable for active distribution networks. The output of the power flow calculation includes at least the voltage magnitude and phase angle of each node, where the voltage magnitude of node i is taken as the node voltage before the sag under distributed photovoltaic access conditions.

[0072] The node voltage under the baseline operating condition and the node voltage before the voltage dip under the distributed photovoltaic (PV) access condition should be compared under the same network topology, load condition and voltage reference, so that the difference between the two mainly reflects the steady-state voltage support effect generated by the distributed PV access.

[0073] The steady-state support correction result can be obtained through the steady-state support correction coefficient. express:

[0074] in, The node voltage is under conditions of no photovoltaic or reference operation. This refers to the node voltage before the voltage dip after photovoltaic (PV) integration. This is the steady-state support correction coefficient.

[0075] The underlying risk of temporary decline is then corrected based on the steady-state support correction results, resulting in the temporary decline risk profile value for each node. for:

[0076] in, A positive number is set to prevent the denominator from being zero. The larger the value, the more priority node i needs to be guaranteed in representative sag scenarios. This risk profile reflects not only the magnitude and duration of the sag, but also the difference between the importance of sensitive loads and the steady-state support of photovoltaics.

[0077] In some embodiments, based on operational data and scenario data, the voltage recovery effect of the dynamic voltage restorer on each node under multiple voltage sag scenarios when it is set at each candidate access bus location is determined, and the recovery influence domain corresponding to each candidate access bus location is determined based on the voltage recovery effect. This includes: applying a preset compensation effect to each candidate access bus location under each voltage sag scenario; determining the node voltage increment generated by the preset compensation effect transmitted from the corresponding candidate access bus location to each node based on operational data, so as to obtain the voltage recovery effect of the corresponding candidate access bus location on each node under each voltage sag scenario; determining the compensated voltage of each node based on the node voltage increment and the sag voltage of each node under the corresponding voltage sag scenario; establishing a recovery coverage relationship between the candidate access bus locations, nodes, and voltage sag scenarios where the compensated voltage reaches the preset recovery target, and determining the recovery influence domain corresponding to each candidate access bus location based on the recovery coverage relationship.

[0078] The preset compensation effect can be either a unit compensation voltage or a preset unit capacity compensation effect. Using a unit compensation effect can separate the recovery transmission capability of the candidate access bus location itself from the specific configured capacity, which facilitates the rapid estimation of node recovery results for different configured capacities in subsequent site selection and capacity optimization.

[0079] For the candidate bus access location c, a dynamic voltage restorer can be set in the simulation model corresponding to scenario ω, and a unit compensation amount u can be applied to the candidate bus access location. c Record the voltage changes at each node.

[0080] The voltage recovery transfer coefficient from candidate access bus location c to node i in scenario ω can be denoted as: When expressed using linearization, the node voltage increment can be represented as:

[0081] in, It can be obtained from transient simulation. For the candidate capacity S... c The compensated voltage estimate of node i in scene ω is:

[0082] Then, the coverage indication of node i at candidate access bus position c in scene ω can be expressed as:

[0083] In the formula, The three-dimensional relationships constitute the restored influence domain matrix A, that is The restored influence domain matrix represents the three-dimensional relationship between candidate bus access locations, nodes, and voltage sag scenarios. For the same candidate bus access location, the set of controlled nodes corresponding to it can be different under different voltage sag scenarios; for the same node, effective restoration can also be provided by different candidate bus access locations under different scenarios.

[0084] For example, candidate access bus position c1 can enable nodes 1, 2 and 3 to achieve the recovery target in scenario ω1, but can only enable nodes 1 and 2 to achieve the recovery target in scenario ω2. Therefore, it has different recovery influence domains in the two scenarios.

[0085] By adopting the above-mentioned restoration coverage relationship, it is not necessary to pre-divide the target active distribution network into fixed areas, thereby avoiding the restoration coverage blind spots caused by the inconsistency between the network partition boundary and the voltage sag propagation range.

[0086] In some embodiments, before jointly optimizing the access bus location and configuration capacity of the target dynamic voltage restorer, the method further includes: determining the risk coverage benefit corresponding to each candidate access bus location based on the sag risk profile corresponding to each node, the probability of occurrence of each voltage sag scenario, and the recovery influence domain corresponding to each candidate access bus location; determining the capacity requirement corresponding to each candidate access bus location based on the configuration capacity required for each candidate access bus location to enable nodes within the corresponding recovery influence domain to reach a preset recovery target; comparing the risk coverage benefit, capacity requirement, and configuration cost corresponding to each candidate access bus location to determine the dominance relationship between candidate access bus locations; deleting candidate access bus locations that are dominated by other candidate access bus locations in terms of risk coverage benefit, capacity requirement, and configuration cost, obtaining a set of effective candidate access bus locations, and performing joint optimization based on the set of effective candidate access bus locations.

[0087] To reduce the optimization scale and eliminate inefficient candidates, a dominance relationship assessment is performed on the candidate bus. A risk coverage return B is defined for candidate bus c. c :

[0088] in, =1 indicates that candidate access bus position c can enable node i to achieve the recovery target under scenario ω. The greater the risk coverage benefit, the more high-risk nodes and high-probability scenarios the candidate access bus position can cover.

[0089] Temporary risk profile ρ i Used to reflect the comprehensive governance priority at the node level, the probability of scenario occurrence p ω This is used to further demonstrate the coverage value of candidate access bus locations in specific scenarios.

[0090] For candidate access bus location c, the capacity required for the node to achieve the recovery target under each representative voltage sag scenario can be determined. The maximum capacity required by multiple scenarios will be used as the capacity requirement for the candidate access bus location:

[0091] in, For capacity requirements, the capacity required for node iii to achieve the recovery target in scenario ω at candidate access bus position c can be determined, for example, by the following formula:

[0092] In the formula, This represents the voltage recovery coefficient per unit capacity. The capacity requirement of the candidate access bus location in scenario ω can be taken as the maximum value of the capacity required by each node under that scenario and guaranteed by the candidate access bus location.

[0093] For two candidate access bus locations c and r, when the following condition is met: risk coverage benefit B r ≥ Risk Coverage Return Threshold B c S r req ≤ Risk Coverage and Return Threshold S c req Configuration cost k r ≤Maximum allowable cost of configuration k c If at least one inequality holds strictly, then the candidate bus c is considered to be dominated by r, and c is removed from the candidate set. The filtered candidate set is denoted as C′.

[0094] This dominance relationship indicates that candidate access bus location r can achieve a risk coverage benefit no less than that of candidate access bus location c, while requiring no more capacity and having no higher unit capacity cost. Therefore, candidate access bus location c can be deleted without sacrificing risk coverage capability. Dominance relationship deletion is a candidate preprocessing performed before joint optimization. It does not directly determine the final access bus location but reduces significantly inefficient candidates. This reduces the number of optimization variables and minimizes the interference of candidate access bus locations with highly overlapping influence domains, large capacity requirements, and high costs on the solution process.

[0095] In some embodiments, based on the sag risk profile corresponding to each node and the recovery influence domain corresponding to each candidate access bus location, under preset configuration constraints, the access bus location and configuration capacity of the target dynamic voltage restorer are jointly optimized to obtain an initial configuration scheme. This includes: determining the uncovered risk corresponding to the uncovered risk variable based on the sag risk profile corresponding to each node and the scenario occurrence probability corresponding to each voltage sag scenario; determining the capacity configuration cost of the dynamic voltage restorer based on the configuration capacity and unit capacity cost corresponding to each candidate access bus location; determining the redundant coverage cost based on the degree of overlap coverage of the recovery influence domain of multiple configured dynamic voltage restorers on the same node in the same voltage sag scenario; establishing a coverage-capacity joint optimization model with reducing uncovered risk, capacity configuration cost, and redundant coverage cost as the joint optimization objective; solving the coverage-capacity joint optimization model based on preset configuration constraints to determine the access bus location of the dynamic voltage restorer from multiple candidate access bus locations and determine the configuration capacity corresponding to the access bus location, thereby obtaining the initial configuration scheme; wherein, the preset configuration constraints include node scenario coverage constraints, candidate access bus location capacity constraints, and configuration budget constraints.

[0096] Specifically, the weighted composite objective of minimizing the risk of uncovered coverage, DVR configuration capacity, investment costs, and redundancy compensation for excessive overlap is set as variable x. c This indicates whether candidate bus c is configured with a DVR, the continuous variable Sc represents the configured capacity of candidate bus c, and the continuous variable y i ω Let represent the slack in the uncovered risk of node i in scenario ω. The following optimization model is established:

[0097] The first term represents the risk of not being covered, the second term represents the DVR capacity and investment cost, the third term represents the penalty for excessive overlap compensation or redundant configuration, and λ1, λ2, and λ3 are weighting coefficients. This represents the redundancy coverage penalty for node i in scene ω; The constraints include:

[0098] The above formula represents the node scene coverage constraint, used to ensure that the required combination of node scenes can be covered by at least one configured DVR; if complete coverage is not possible, then a relaxation amount for the coverage risk is applied. This reflects the degree to which its needs are not met. This is a binary decision parameter indicating whether node i must be guaranteed in scenario ω. If the node's risk profile value is higher than a set threshold, it means that there is a governance requirement for that node in the scenario. This is the mandatory protection indicator for node i in scenario ω. When node i experiences a voltage sag requiring mitigation in scenario ω, and its node risk profile value exceeds a preset risk threshold, or the node is a highly sensitive load, an important user, or a user requiring mandatory protection, this value is taken as... =1 indicates that the optimization model should prioritize ensuring that the node is covered by at least one DVR influence domain in this scenario; otherwise, take... =0 indicates that the node is not a mandatory overwrite object in this scenario.

[0099]

[0100] The above formula represents the DVR capacity constraint, used to limit the configuration capacity S of candidate bus c. c Not exceeding its maximum allowable capacity .

[0101]

[0102] The above formula represents the budget and variable value constraints, used to limit the total investment of all configured DVRs to not exceed the preset configuration budget BUD.

[0103]

[0104] Among them, the redundancy coverage penalty This is used to characterize the degree of excessive overlap compensation when multiple DVR configurations simultaneously cover the same node and the same temporary landing scenario. It can be represented by a coverage indicator. and installation decision variables Sure.

[0105] The weight coefficients in the objective function of the optimization model can be determined by normalization according to different dimensions, so as to avoid a certain objective from dominating the optimization result due to its large numerical scale rather than its actual importance.

[0106] In some embodiments, the voltage recovery results of each node under multiple voltage sag scenarios are verified according to the initial configuration scheme, and the initial configuration scheme is iteratively corrected based on the voltage recovery results that do not meet the preset recovery target to obtain the target configuration scheme of the target dynamic voltage restorer. This includes: determining the compensated voltage of each node under each voltage sag scenario based on the access bus location and configuration capacity in the initial configuration scheme, comparing the compensated voltage with the preset recovery target, and determining the nodes that do not meet the preset recovery target and their corresponding voltage sag scenarios; generating uncovered risk constraints based on the nodes that do not meet the preset recovery target and their corresponding voltage sag scenarios, and adding the uncovered risk constraints to the optimization model corresponding to the joint optimization; and then, in the selected access... When the configured capacity of a bus location does not reach the corresponding capacity limit, the configured capacity of the selected access bus locations is adjusted based on the coverage risk constraint. If there are still nodes that have not reached the preset recovery target after the configuration capacity is adjusted, the alternative access bus locations are determined according to the coverage risk reduction amount and the newly added configuration capacity corresponding to each candidate access bus location. The initial configuration scheme is updated according to the adjusted configuration capacity and / or the alternative access bus locations, and the voltage recovery results of each node under multiple voltage sag scenarios are re-verified based on the updated configuration scheme until the compensated voltage of each node reaches the preset recovery target, or the configuration capacity and / or configuration cost reaches the constraint boundary corresponding to the preset configuration constraint. The configuration scheme at the end of the iteration is determined as the target configuration scheme.

[0107] The actual compensated voltage of node i under scenario ω was obtained through simulation. and compare it with the target voltage recovery. Compare. When: ≥ If the condition is met, it is determined that node i has reached the recovery target under scenario ω; otherwise, it is determined that the scenario combination of the node still has the risk of being uncovered.

[0108] In step S3, the recovery influence domain is estimated using unit compensation or linearization. In step S5, the actual configuration capacity and detailed simulation are used for verification, forming a fast estimation-detailed verification relationship. This approach controls the computational scale of joint optimization and avoids linearization errors that could prevent the final configuration scheme from achieving the recovery target.

[0109] For each access bus location selected in the initial configuration scheme, the simulation calculation should consider the combined effect of multiple dynamic voltage restorers simultaneously, rather than simply adding up the recovery amplitudes of each dynamic voltage restorer independently. When there is control coupling, capacity saturation, or injection voltage limit among the dynamic voltage restorers, the actual compensated voltage obtained from the simulation should be used as the verification basis.

[0110] The recovery verification can output a node-scene recovery matrix, whose elements record the voltage of each node after compensation in each scene, whether the recovery target has been achieved, and the difference between the recovery target and the target.

[0111] For node i and scenario ω that have not achieved the recovery target, an uncovered risk constraint can be generated:

[0112] in, Indicates capacity is When the dynamic voltage restorer is set at the candidate access bus position c, it provides the actual voltage recovery amplitude to node i under scenario ω.

[0113] Compared with the linear recovery transfer coefficient in step S3, It can be determined based on detailed simulation, capacity-recovery range lookup table, or piecewise linear fitting results.

[0114] Adding new uncovered risk constraints to the coverage-capacity joint optimization model requires subsequent updated configuration schemes to provide sufficient recovery for identified uncovered node scenario combinations. Since the new constraints are only generated for nodes and scenarios that do not meet the recovery targets, incremental modifications can be made while retaining the main structure of the original initial configuration scheme.

[0115] First, determine if the selected access bus location in the initial configuration scheme, which can provide recovery for uncovered nodes, still has remaining capacity. When the selected access bus location c satisfies: S c c max In such cases, the capacity can be increased at the candidate access bus location. The increased capacity can be determined based on the recovery voltage gap of the uncovered node, the corresponding recovery transmission relationship, and the product capacity level.

[0116] Prioritizing the increase of the configuration capacity of the selected access bus locations can avoid directly adding new equipment installation locations when the original plan still has capacity expansion space, thereby reducing additional civil engineering, wiring and operation and maintenance costs.

[0117] When all selected access bus locations have reached their capacity limits, or when increasing their configured capacity still fails to restore the uncovered nodes to their recovery target, a substitute access bus location will be selected from the unselected candidate access bus locations.

[0118] The marginal risk reduction rate corresponding to candidate access bus position c can be expressed as:

[0119] in, ​This indicates the reduction in uncovered risk after adding candidate access bus position c or increasing its configured capacity. This indicates the corresponding newly added configuration capacity.

[0120] The amount of risk reduction not covered can be determined based on the temporary risk profile and the probability of occurrence of the scenarios corresponding to the node scenarios that are restored after the configuration is added. For example:

[0121] in, , These represent the uncovered state of node i in scenario ω before and after adding candidate access bus position c.

[0122] A higher marginal risk reduction rate means that each unit of newly added capacity can reduce more uncovered risks. Therefore, the candidate access bus location with the highest marginal risk reduction rate can be prioritized as the backup access bus location.

[0123] When increasing the configured capacity for a selected access bus location, update the corresponding capacity variable S. c When adding a backup bus access location, the installation decision variable x corresponding to the candidate bus access location is... c Update from zero to one and determine the corresponding configuration capacity.

[0124] After the update, the following needs to be recalculated: The actual recovery rate of the updated configuration scheme under various voltage sag scenarios; Uncovered risk variables corresponding to each node scenario combination; Redundant coverage variables for multiple dynamic voltage restorers in the same node scenario combination; The updated configuration plan's capacity configuration cost and total investment; Whether the newly added uncovered risk constraints have been met.

[0125] Then, the coverage-capacity joint optimization model is resolved, and a recovery check is performed again for all representative voltage sag scenarios. This process is iterated until at least one of the following termination conditions is met: First, the voltage of each node requiring protection reaches the recovery target after compensation in each representative voltage sag scenario. The capacity constraints and configuration budget constraints of the dynamic voltage restorer are met, and no new uncovered risk constraints are generated. Second, the configured capacity of the selected access bus locations has reached the corresponding capacity limit, and the configuration cost has reached the preset configuration budget boundary, making it impossible to continue to increase the capacity or add alternative access bus locations under the existing constraints.

[0126] When the first termination condition is met, the configuration scheme that meets all protection requirements is identified as the target configuration scheme. When the second termination condition is met, the configuration scheme with the lowest current uncovered risk is identified as the target configuration scheme under budget and capacity constraints. At the same time, the nodes and scenarios that still do not meet the recovery target are output for engineers to adjust the constraints or increase the investment budget.

[0127] The target configuration scheme may include the bus number of the dynamic voltage restorer installation, the configuration capacity of each dynamic voltage restorer, the compensated voltage of each node in each representative voltage sag scenario, the node risk coverage status, the node non-coverage risk, the marginal risk reduction rate of the candidate access bus location, and alternative configuration schemes under different investment budgets.

[0128] The candidate bus access locations can be ranked according to risk coverage benefits, marginal risk reduction rate, or risk reduction per unit investment. Engineers can directly determine whether high-risk nodes have achieved their recovery targets based on the target configuration scheme, and can also compare changes in the installation location and configuration capacity of dynamic voltage restorers under different investment budgets.

[0129] The above output results establish a traceable relationship between risk profile, recovery impact area, installation location, configuration capacity, and recovery results, facilitating engineering review of dynamic voltage restorer configuration schemes.

[0130] Based on the same inventive concept, this application also provides an active distribution network voltage sag suppression configuration system for implementing the active distribution network voltage sag suppression configuration method described above.

[0131] The solution provided by this system is similar to the solution described in the above method. Therefore, the specific limitations of one or more active distribution network voltage sag suppression configuration system embodiments provided below can be found in the limitations of the active distribution network voltage sag suppression configuration method above, and will not be repeated here.

[0132] like Figure 3 As shown in the figure, this application provides an active distribution network voltage sag suppression configuration system, which includes: The data acquisition module 100 is used to acquire the operation data of the target active distribution network and the scenario data corresponding to multiple voltage sag scenarios; The profile building module 200 is used to determine the voltage sag characteristics of each node in multiple voltage sag scenarios based on scenario data, and to build a voltage sag risk profile for each node based on the voltage sag characteristics and the node assurance requirements of each node. The influence domain determination module 300 is used to determine the voltage recovery effect of the dynamic voltage restorer on each node under multiple voltage sag scenarios when it is set at each preset candidate access bus position, based on the operation data and scenario data, and to determine the recovery influence domain corresponding to each candidate access bus position based on the voltage recovery effect. The initial configuration determination module 400 is used to jointly optimize the access bus location and configuration capacity of the target dynamic voltage restorer based on the sag risk profile of each node and the recovery influence domain corresponding to each candidate access bus location, under preset configuration constraints, to obtain the initial configuration scheme. The target configuration determination module 500 is used to verify the voltage recovery results of each node under multiple voltage sag scenarios according to the initial configuration scheme, and to iteratively correct the initial configuration scheme based on the voltage recovery results that do not reach the preset recovery target, so as to obtain the target configuration scheme of the target dynamic voltage restorer.

[0133] In some embodiments, the portrait construction module 200 is used for: Based on the difference between the preset governance threshold and the voltage sag of each node in each voltage sag scenario, determine the voltage sag amplitude gap of each node in each voltage sag scenario. Based on the voltage sag amplitude gap, voltage sag duration, and scenario occurrence probability of each node, the scenario sag risk of each node under each voltage sag scenario is determined; Based on at least one of the load type, user level, and power supply priority corresponding to each node, the load importance corresponding to each node is determined, and the scenario sag risk of each node is weighted and aggregated according to the load importance to obtain the basic sag risk corresponding to each node. Based on the node voltage of each node under the baseline operating state and the node voltage before the voltage dip under the distributed photovoltaic access state, the steady-state support correction result for each node is determined. Based on the steady-state support correction results, the temporary reduction risk is corrected to obtain the temporary reduction risk profile for each node.

[0134] In some embodiments, the portrait construction module 200 is used for: Obtain the operating parameters of distributed photovoltaic (PV) systems, determine the active power output and reactive power regulation range of distributed PV systems based on the operating parameters, and determine the distribution network operation point under the distributed PV access state based on the active power output and reactive power regulation range. Based on the power flow calculation of the distribution network operating point, the node voltage before the sag of each node under the distributed photovoltaic access state is obtained; The voltage support amount of the node voltage before the voltage sag is determined relative to the node voltage under the reference operating state, and the steady-state support correction result is determined based on the voltage support amount; wherein, the steady-state support correction result characterizes the degree of steady-state voltage support provided by distributed photovoltaic to the corresponding node before the voltage sag occurs.

[0135] In some embodiments, the influence domain determination module 300 is configured to: For each candidate access bus location, a preset compensation effect is applied to the corresponding candidate access bus location under each voltage sag scenario; Based on the operational data, the node voltage increment generated by the preset compensation effect transmitted to each node from the corresponding candidate access bus position is determined, so as to obtain the voltage recovery effect of the corresponding candidate access bus position on each node under each voltage sag scenario. Based on the node voltage increment and the voltage sag of each node in the corresponding voltage sag scenario, determine the compensated voltage of each node; Establish a recovery coverage relationship for candidate access bus locations, nodes, and voltage sag scenarios where the compensated voltage reaches the preset recovery target, and determine the recovery influence domain corresponding to each candidate access bus location based on the recovery coverage relationship.

[0136] In some embodiments, the system further includes a bus access optimization module, used for: Based on the risk profile of each node, the probability of occurrence of each voltage sag scenario, and the recovery impact domain of each candidate access bus location, the risk coverage benefit of each candidate access bus location is determined. Based on the configuration capacity required for the nodes within the corresponding recovery impact domain to reach the preset recovery target according to the location of each candidate access bus, determine the capacity requirement corresponding to each candidate access bus location. The risk coverage benefits, capacity requirements, and configuration costs corresponding to each candidate access bus location are compared to determine the dominance relationship between the candidate access bus locations. Candidate access bus locations that are dominated by other candidate access bus locations in terms of risk coverage benefits, capacity requirements, and configuration costs are removed, resulting in a set of effective candidate access bus locations. Joint optimization is then performed based on this set of effective candidate access bus locations.

[0137] In some embodiments, the initial configuration determination module 400 is configured to: Based on the voltage sag risk profile for each node and the probability of occurrence for each voltage sag scenario, the uncovered risks corresponding to the uncovered risk variables are determined. The capacity configuration cost of the dynamic voltage restorer is determined based on the configuration capacity and unit capacity cost corresponding to each candidate access bus location. The redundancy coverage cost is determined based on the degree of overlap of the recovery influence domains of multiple configured dynamic voltage restorers on the same node in the same voltage sag scenario. A joint optimization model for coverage and capacity is established with the joint optimization objectives of reducing the risk of uncovered coverage, the cost of capacity configuration, and the cost of redundant coverage. Based on preset configuration constraints, the coverage-capacity joint optimization model is solved to determine the access bus position of the dynamic voltage restorer from multiple candidate access bus positions, and to determine the configuration capacity corresponding to the access bus position, thus obtaining an initial configuration scheme. The preset configuration constraints include node scenario coverage constraints, candidate access bus position capacity constraints, and configuration budget constraints.

[0138] In some embodiments, the target configuration determination module 500 is configured to: Based on the access bus location and configuration capacity in the initial configuration scheme, determine the compensated voltage of each node in each voltage sag scenario, and compare the compensated voltage with the preset recovery target to determine the nodes that have not reached the preset recovery target and the corresponding voltage sag scenarios. Based on the nodes that have not reached the preset recovery target and the corresponding voltage sag scenarios, uncovered risk constraints are generated, and the uncovered risk constraints are added to the optimization model corresponding to the joint optimization. When the configured capacity of the selected access bus location does not reach the corresponding capacity limit, the configured capacity of the selected access bus location is adjusted based on the coverage risk constraint. If there are still nodes that do not reach the preset recovery target after adjusting the configured capacity, the substitute access bus location is determined according to the coverage risk reduction amount and the newly added configured capacity corresponding to each candidate access bus location. The initial configuration scheme is updated based on the adjusted configuration capacity and / or the location of the backup access bus. The voltage recovery results of each node under multiple voltage sag scenarios are re-verified based on the updated configuration scheme until the compensated voltage of each node reaches the preset recovery target, or the configuration capacity and / or configuration cost reaches the constraint boundary corresponding to the preset configuration constraint. The configuration scheme at the end of the iteration is then determined as the target configuration scheme.

[0139] like Figure 4 As shown, this application provides an electronic device. The electronic device 10 includes a memory 20 and a processor 30. The memory 20 stores a computer program. When the computer program is executed by the processor 30, the processor 30 performs the steps of the active distribution network voltage sag suppression configuration method as described in the above embodiment.

[0140] This application provides a computer-readable storage medium storing a computer program thereon, which, when executed, implements the steps of the active distribution network voltage sag suppression configuration method as described in the above embodiments.

[0141] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, electronic devices, and computer storage media described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0142] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0143] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification, claims and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products or devices.

[0144] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0145] In the embodiments provided by this invention, it should be understood that the disclosed systems, electronic devices, computer storage media, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units through some interfaces, and may be electrical, mechanical, or other forms.

[0146] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0147] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0148] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of the present invention through a computer device (which may be a personal computer, a server, or a network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0149] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for configuring active distribution network voltage sag suppression, characterized in that, The method includes: Acquire operational data of the target active distribution network and scenario data corresponding to multiple voltage sag scenarios; Based on the scenario data, determine the voltage sag characteristics of each node under the multiple voltage sag scenarios, and construct a voltage sag risk profile for each node based on the voltage sag characteristics and the node assurance requirements of each node. Based on the operational data and the scenario data, determine the voltage recovery effect of the dynamic voltage restorer on each node under the multiple voltage sag scenarios when it is set at each preset candidate access bus position, and determine the recovery influence domain corresponding to each candidate access bus position based on the voltage recovery effect. Based on the transient risk profile of each node and the recovery influence domain corresponding to each candidate access bus location, the access bus location and configuration capacity of the target dynamic voltage restorer are jointly optimized under preset configuration constraints to obtain an initial configuration scheme. The voltage recovery results of each node under the multiple voltage sag scenarios are verified according to the initial configuration scheme. Based on the voltage recovery results that do not meet the preset recovery target, the initial configuration scheme is iteratively corrected to obtain the target configuration scheme of the target dynamic voltage restorer.

2. The active distribution network voltage sag suppression configuration method according to claim 1, characterized in that, The process involves determining the voltage sag characteristics of each node under the multiple voltage sag scenarios based on the scenario data, and constructing a voltage sag risk profile for each node based on the voltage sag characteristics and the node assurance requirements of each node, including: Based on the difference between the preset governance threshold and the voltage sag of each node in each voltage sag scenario, the voltage sag amplitude gap of each node in each voltage sag scenario is determined. Based on the voltage sag amplitude gap, voltage sag duration, and scenario occurrence probability of each node, determine the scenario sag risk of each node under each voltage sag scenario; Based on at least one of the load type, user level, and power supply priority corresponding to each node, the load importance corresponding to each node is determined, and the scenario sag risk of each node is weighted and aggregated according to the load importance to obtain the basic sag risk corresponding to each node. Based on the node voltage of each node under the baseline operating state and the node voltage before the voltage dip under the distributed photovoltaic access state, the steady-state support correction result for each node is determined. Based on the steady-state support correction results, the temporary drop risk is corrected to obtain the temporary drop risk profile for each node.

3. The active distribution network voltage sag suppression configuration method according to claim 2, characterized in that, The determination of the steady-state support correction result for each node based on the node voltage under the baseline operating state and the node voltage before the voltage dip under the distributed photovoltaic grid connection state includes: Obtain the operating parameters of the distributed photovoltaic system, determine the active power output and reactive power adjustment range of the distributed photovoltaic system based on the operating parameters, and determine the distribution network operation point under the distributed photovoltaic system access state based on the active power output and the reactive power adjustment range. Based on the power flow calculation of the distribution network operating point, the node voltage before the sag of each node under the distributed photovoltaic access state is obtained; The voltage support amount of the node voltage before the voltage sag is determined relative to the node voltage of the corresponding node under the reference operating state, and the steady-state support correction result is determined based on the voltage support amount; wherein, the steady-state support correction result characterizes the degree of steady-state voltage support provided by distributed photovoltaic to the corresponding node before the voltage sag occurs.

4. The active distribution network voltage sag suppression configuration method according to claim 1, characterized in that, The step of determining the voltage recovery effect of each node under multiple voltage sag scenarios when the dynamic voltage restorer is set at each of the candidate access bus locations based on the operating data and the scenario data, and determining the recovery influence domain corresponding to each of the candidate access bus locations based on the voltage recovery effect, includes: For each of the candidate access bus locations, a preset compensation effect is applied to the corresponding candidate access bus location under each of the voltage sag scenarios; Based on the operational data, the node voltage increment generated by the preset compensation effect transmitted from the corresponding candidate access bus position to each node is determined, so as to obtain the voltage recovery effect of the corresponding candidate access bus position on each node in each voltage sag scenario. Based on the node voltage increment and the voltage sag of each node in the corresponding voltage sag scenario, determine the compensated voltage of each node; Establish a recovery coverage relationship for candidate access bus locations, nodes, and voltage sag scenarios where the compensated voltage reaches the preset recovery target, and determine the recovery influence domain corresponding to each candidate access bus location based on the recovery coverage relationship.

5. The active distribution network voltage sag suppression configuration method according to claim 1, characterized in that, Before jointly optimizing the access bus location and configuration capacity of the target dynamic voltage restorer, the method further includes: Based on the voltage sag risk profile corresponding to each node, the probability of occurrence of each voltage sag scenario, and the recovery impact domain corresponding to each candidate access bus location, the risk coverage benefit corresponding to each candidate access bus location is determined. Based on the configuration capacity required for the nodes within the corresponding recovery influence domain to reach the preset recovery target according to the location of each candidate access bus, the capacity requirement corresponding to each candidate access bus location is determined. The risk coverage benefits, capacity requirements, and configuration costs corresponding to each of the candidate access bus locations are compared to determine the dominance relationship between the candidate access bus locations. Candidate access bus locations that are dominated by other candidate access bus locations in terms of risk coverage benefits, capacity requirements, and configuration costs are removed to obtain a set of effective candidate access bus locations, and the joint optimization is performed based on the set of effective candidate access bus locations.

6. The active distribution network voltage sag suppression configuration method according to claim 1, characterized in that, Based on the transient risk profile of each node and the recovery influence domain corresponding to each candidate access bus location, and under preset configuration constraints, the access bus location and configuration capacity of the target dynamic voltage restorer are jointly optimized to obtain an initial configuration scheme, including: Based on the voltage sag risk profile corresponding to each node and the probability of occurrence of each voltage sag scenario, the uncovered risk corresponding to the uncovered risk variable is determined; The capacity configuration cost of the dynamic voltage restorer is determined based on the configuration capacity and unit capacity cost corresponding to each of the candidate access bus locations. The redundancy coverage cost is determined based on the degree of overlap of the recovery influence domains of multiple configured dynamic voltage restorers on the same node in the same voltage sag scenario. A joint optimization model for coverage and capacity is established with the joint optimization objectives of reducing the risk of uncovering, the cost of capacity configuration, and the cost of redundant coverage. Based on the preset configuration constraints, the coverage-capacity joint optimization model is solved to determine the access bus position of the dynamic voltage restorer from multiple candidate access bus positions, and to determine the configuration capacity corresponding to the access bus position, thereby obtaining the initial configuration scheme; wherein, the preset configuration constraints include node scenario coverage constraints, candidate access bus position capacity constraints, and configuration budget constraints.

7. The active distribution network voltage sag suppression configuration method according to claim 1, characterized in that, The process involves verifying the voltage recovery results of each node under multiple voltage sag scenarios according to the initial configuration scheme, and iteratively revising the initial configuration scheme based on the voltage recovery results that fail to meet the preset recovery target, to obtain the target configuration scheme for the target dynamic voltage restorer, including: Based on the access bus location and configuration capacity in the initial configuration scheme, the compensated voltage of each node in each voltage sag scenario is determined, and the compensated voltage is compared with the preset recovery target to determine the nodes that have not reached the preset recovery target and the corresponding voltage sag scenarios. Based on the nodes that have not reached the preset recovery target and the corresponding voltage sag scenarios, an uncovered risk constraint is generated, and the uncovered risk constraint is added to the optimization model corresponding to the joint optimization. When the configured capacity of the selected access bus location does not reach the corresponding capacity limit, the configured capacity of the selected access bus location is adjusted based on the uncovered risk constraint. If there are still nodes that do not reach the preset recovery target after adjusting the configured capacity, the substitute access bus location is determined according to the uncovered risk reduction amount and the newly added configured capacity corresponding to each candidate access bus location. The initial configuration scheme is updated based on the adjusted configuration capacity and / or the location of the substitute access bus. The voltage recovery results of each node under the multiple voltage sag scenarios are re-verified based on the updated configuration scheme until the compensated voltage of each node reaches the preset recovery target, or the configuration capacity and / or configuration cost reaches the constraint boundary corresponding to the preset configuration constraint. The configuration scheme at the end of the iteration is then determined as the target configuration scheme.

8. An active distribution network voltage sag suppression configuration system, characterized in that, The system includes: The data acquisition module is used to acquire the operation data of the target active distribution network and the scenario data corresponding to multiple voltage sag scenarios; The profile building module is used to determine the voltage sag characteristics of each node under the multiple voltage sag scenarios based on the scenario data, and to build a sag risk profile for each node based on the voltage sag characteristics and the node assurance requirements of each node. The influence domain determination module is used to determine the voltage recovery effect of the dynamic voltage restorer on each node under the multiple voltage sag scenarios when it is set at each preset candidate access bus position, based on the running data and the scenario data, and to determine the recovery influence domain corresponding to each candidate access bus position based on the voltage recovery effect. The initial configuration determination module is used to jointly optimize the access bus position and configuration capacity of the target dynamic voltage restorer under preset configuration constraints, based on the temporary descent risk profile of each node and the recovery influence domain corresponding to each candidate access bus position, to obtain an initial configuration scheme. The target configuration determination module is used to verify the voltage recovery results of each node under the multiple voltage sag scenarios according to the initial configuration scheme, and to iteratively correct the initial configuration scheme according to the voltage recovery results that do not reach the preset recovery target, so as to obtain the target configuration scheme of the target dynamic voltage restorer.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores a computer program, which, when executed by the processor, causes the processor to perform the steps of the active distribution network voltage sag suppression configuration method as described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the steps of the active distribution network voltage sag suppression configuration method as described in any one of claims 1-7.

Images