Micro-grid network architecture planning method and system based on multi-objective optimization and scenario simulation

Abstract

The application discloses a micro-grid network framework planning method and system based on multi-objective optimization and scenario simulation, and particularly relates to the technical field of micro-grid network framework planning and optimization, which comprises the following steps: collecting the first-period access subject record, the distributed power record, the energy storage access record, the line record and the switch connection record of the gathering park, performing corresponding arrangement on all kinds of records, generating an initial network framework diagram, a partition table and a power table; performing social simulation on the subsequent access position according to the type table of the subject to be introduced, the expansion time sequence table and the park subject replacement process, generating multiple groups of subject replacement scenarios, and solving the newly added power drop point, the power exchange direction, the power supply recovery sequence and the energy storage support position for each subject replacement scenario to form a scenario result table; and corresponding the multiple access scenarios formed by the park subject replacement with the candidate network framework one by one, and performing joint deduction and screening around the alternating current feeder bearing, the tie line transfer supply, the energy storage support and the locking relationship.

Description

Technical Field

[0001] This invention relates to the field of microgrid network planning and optimization technology, and more specifically, to a microgrid network planning method and system based on multi-objective optimization and scenario simulation. Background Technology

[0002] In the design of park-type microgrid network, the existing technology focuses on meeting the requirements of power supply reliability, distributed power source access and subsequent expansion after the first phase of construction is completed. In engineering, the power supply zone division, connection location selection, switch configuration and capacity reservation are generally completed based on the installed capacity of the main entities, typical load sequence, proposed energy storage scale and line channel conditions. Taking a park that has already formed a mixed energy use system for office and light industry in the first phase, and still needs to continuously introduce cold chain storage, data center and fast charging station as an example, the implementation process requires that the grid structure formed in the first phase can be put into operation directly, and that when new entities are connected in the future, the existing main wiring should not be changed as much as possible, the location of the existing energy storage should not be relocated, and the original zonal power supply relationship and fault transfer path should continue to be used. However, in this situation, a verifiable situation repeatedly occurs on site: although the existing line capacity, transformer capacity, and site space all show that there is still a surplus, once a new entity with significantly different energy consumption time distribution, power restoration sequence, and power exchange direction is introduced, the original grid will experience phenomena such as mismatch in zonal load-bearing direction, difficulty in connecting locations to accommodate new power exchange, and energy storage landing points deviating from the center of gravity of new loads. As a result, new access often requires dismantling and modifying the main wiring, redrawing power supply zones, or adding transitional facilities. The root cause is that the existing design mainly leaves room for capacity growth, without judging in advance whether the existing grid will still have the ability to continue to expand along the original structure after the main structure of the park changes. The technical problem this application aims to solve is: how to identify and avoid the restrictive effects of subsequent changes in the main structure on the expansion direction of the existing grid during the microgrid grid planning stage. Summary of the Invention

[0003] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide a microgrid grid planning method and system based on multi-objective optimization and scenario simulation. By mapping various access scenarios formed by the replacement of the main body of the park to candidate grids one by one, and performing joint deduction and screening around AC feeder carrying, interconnection and transfer, energy storage support and locking relationship, the problems mentioned in the background art are solved.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a microgrid network planning method based on multi-objective optimization and scenario simulation, comprising: S1. Collect the initial access records of the park, distributed power source records, energy storage access records, line records and switch connection records, and perform corresponding sorting on various records to generate the initial network diagram, partition table and power table; S2. Based on the proposed main body type table, expansion timeline table and park main body replacement process, perform social simulation on subsequent access locations to generate multiple main body replacement scenarios. For each main body replacement scenario, solve the new power landing point, power exchange direction, power supply restoration sequence and energy storage support location to form a scenario result table. S3. Based on the location of the interconnection switch, the location of the partition boundary and the location of the energy storage access in the initial grid diagram, perform location changes to generate candidate grid groups, and match each candidate grid with the scenario result table to form a grid scenario comparison table. S4. For the grid structure scenario comparison table, perform power flow calculation, power transfer path calculation and recovery path calculation for each candidate grid structure in each main body replacement scenario, identify whether there are main wiring changes, partition re-division and energy storage relocation, and generate a locking record table. S5. Based on the locking record table, candidate grid structures that have undergone main wiring changes, zoning re-division, or energy storage relocation are eliminated. Then, construction investment calculation, power supply reliability calculation, distributed power source absorption calculation, and subsequent modification count calculation are performed on the remaining candidate grid structures, and the target microgrid grid structure planning results are output.

[0005] In a preferred embodiment, S1 includes: S11. Perform node attribution sorting on the first phase access entity record, distributed power source record, energy storage access record, line record and switch connection record of the park, write the first phase access entity, distributed power source and energy storage access point into the corresponding line endpoint, and output the node connection table. S12. Based on the node connection table, perform feeder connection and segmentation for the beginning and end of the line and the switch connection direction. Write the power supply path formed from the power access point to each load access point and the segmentation boundary formed by the switch disconnection position into the initial network diagram and output the partition table. S13. Based on the initial network diagram and node connection table, perform segmented calculations on the distributed power injection power, energy storage charging and discharging power, and the power taken by the first phase of the connected main body, and write the incoming power, outgoing power, and switching power of each zone into the power table.

[0006] In a preferred embodiment, S2 includes: S21. Read the types and quantities of entities to be introduced in each time period according to the expansion time sequence table. Write the entities to be introduced in each time period into the subsequent access locations one by one. Subtract the new active power demand, new reactive power demand, distributed power injection amount and energy storage replenishment demand of each subsequent access location from the feeder margin, transformer margin and tie switch path in the initial network diagram. Write the subtraction result with negative values ​​into the mismatch scenario table. Write the subtraction result without negative values ​​into the reserved scenario table. Then rearrange the reserved scenario table according to the entry order, exit order and capacity expansion order in the process of replacing the park's entities. Output the entity replacement scenario group. S22. For each main replacement scenario in the main replacement scenario group, read the power supply path between the subsequent access location and the feeder node one by one. Subtract the current carrying capacity of each line segment in the path from the new active power demand and new reactive power demand corresponding to the subsequent access location segment by segment. Write the subtraction results of each line segment in the same path into a path capacity sequence according to the line order. Then sort the path capacity sequence formed by connecting adjacent partitions of each access location through the tie switch in the order of the first segment result, the last segment result, and the cumulative value of each segment result. Output the new power landing point and power exchange direction.

[0007] In a preferred embodiment, S2 further includes: S23. For the power loss zones in each main replacement scenario, first subtract the distributed power injection amount from the zone load amount one by one and write down the local replenishment amount. Then, subtract the power transfer of the part not covered by the local replenishment amount from the transfer power of the adjacent interconnection switch zone one by one and write down the transfer replenishment amount. Then, subtract the remaining discharge amount of each energy storage access location one by one from the part not covered by the transfer replenishment amount and write down the energy storage replenishment amount. Then, accumulate the local replenishment amount, transfer replenishment amount and energy storage replenishment amount according to the writing order until the power loss zone demand is zero, and output the order of power restoration and energy storage support location. S24. Compare the new power landing point, power exchange direction, power restoration order, and energy storage support location in each subject replacement scenario according to time period. Perform same-position counting on the new power landing point obtained by the same subsequent access location in different time periods, perform reverse counting on the power exchange direction, accumulate the position difference on the power restoration order, and accumulate the repetition count on the energy storage support location. Delete scenarios with zero same-position count and positive reverse count, merge scenarios with the same new power landing point and the same energy storage support location, and output the scenario result table.

[0008] In a preferred embodiment, S3 includes: S31. Write the starting node, ending node, tie switch position, zone boundary position, and energy storage access position of the AC feeder segment in the initial network diagram into an original connection table according to the feeder connection order. Perform on / off replacement on each tie switch position, perform parallel replacement or disconnection replacement on each zone boundary position, and perform removal replacement and removal replacement on each energy storage access position. After each replacement, follow up the AC feeder segment segment by segment according to the node connection relationship. Write the power supply path, tie path, and supplementary power path obtained by following up into a candidate connection table and output the candidate network group.

[0009] In a preferred embodiment, S3 further includes: S32. For each candidate grid in the candidate grid group, read the power supply path between the distributed power access point and the new power landing point, the interconnection path corresponding to the power exchange direction, and the supplementary power path corresponding to the energy storage support location according to the candidate connection table. Subtract the rated current value of the line segment in each path from the path power demand value in the scenario result table segment by segment. Add up the number of line segments, the number of switch crossings, and the number of zone crossings in each path. Write the candidate grid with a negative subtraction result into the elimination table. Write the candidate grid with a non-negative subtraction result, along with the accumulated value of the number of path segments, the accumulated value of the number of switch crossings, and the accumulated value of the number of zone crossings, into the retention table. S33. Based on the retention table, sort the candidate grid structures under the same subject replacement scenario in order of the cumulative value of the number of path segments, the cumulative value of the number of switch crossings, and the cumulative value of the number of partition crossings. Write the sorting results into a scenario ranking table, and write the candidate grid structure number, scenario number, power supply path, interconnection path and supplementary power supply path in the scenario ranking table into the grid structure scenario comparison table.

[0010] In a preferred embodiment, S4 includes: S41. Match the candidate grid structures in the grid structure scenario comparison table with the main replacement scenario one by one. Write the load power consumption, distributed power injection, and energy storage charging and discharging into each node according to the node order from the beginning to the end of the AC feeder. Then, perform node power aggregation, line power distribution, and upstream write-back along the feeder segment by segment until the beginning power value obtained from the two write-backs of the same feeder is consistent. Output the scenario power flow table. S42. For the power outage zone in the scenario power flow table, first subtract the distributed power injection amount within the zone from the zone's required power to obtain the local gap amount. Then, for each tie switch, perform line margin deduction and path margin serial writing for each corresponding transfer path segment by segment. Compare the first segment margin, last segment margin, and full segment deduction of each path item by item in the order of first segment, then last segment, and then full segment. Select the transfer path in sequence and fill in the local gap amount. Output the transfer result table.

[0011] In a preferred embodiment, S4 further includes: S43. Based on the power transfer result table, for the non-zero power loss zone, the remaining discharge amount of each energy storage access point is deducted from the line balance segment by segment along the power replenishment path to obtain the power replenishment balance string. Then, the power replenishment balance string is written into the power loss zone item by item according to the order of power restoration. The line power, tie direction and energy storage balance after writing are reverse recalculated. The power replenishment path with negative line balance, reverse tie direction and negative energy storage balance after recalculation is deleted, and the restoration result table is output. S44. Based on the scenario power flow table, power transfer result table, and recovery result table, perform a check on the initial connection relationship and scenario satisfaction relationship for each candidate network structure. Write the changes in feeder connection positions and the scenario power after the change is included in the line rated range as main wiring changes. Write the changes in partition assignment positions and the power restoration order after the change is consistent with the scenario result table as partition redrawing. Write the changes in energy storage access positions and the power demand of the power-loss partition is zero after the change as energy storage relocation. Write the main wiring change record, partition redrawing record, and energy storage relocation record into the lock record table.

[0012] In a preferred embodiment, S5 includes: S51. Read the main wiring modification items, zoning re-division items and energy storage relocation items written in the lockout record table by candidate grid number one by one. Write a rejection mark for candidate grids written in any item. For candidate grids not written in any of the three items, retain the AC feeder section table, tie switch table and energy storage access table. Then, add up the AC feeder section length, tie switch number and energy storage access capacity respectively and write them into the construction investment table. S52. For each reserved candidate grid in the construction input table, divide the number of restored power supply zones in the scenario power flow table by the number of unsupplied power supply zones and write it as the scenario power supply value. Divide the number of power transfer completions in the power transfer result table by the number of power transfer inputs and write it as the scenario power transfer value. Divide the amount of power replenishment completed in the recovery result table by the amount of power replenishment requested and write it as the scenario energy storage value. Divide the amount of power received in the scenario power flow table by the amount of power injected and write it as the scenario absorption value. Then, sum up the scenario power supply value, scenario power transfer value, scenario energy storage value and scenario absorption value according to the scenario order and divide them by the number of scenarios, and write them into the grid result table. S53. Combine the power supply value, transfer value, energy storage value, and absorption value in the grid result table with the cumulative values ​​of AC feeder segment length, tie switch quantity, and energy storage access capacity in the construction investment table to form a result string according to the candidate grid number. For any two result strings, perform the following sorting in sequence: reverse order of power supply value, reverse order of transfer value, reverse order of energy storage value, reverse order of absorption value, sequential order of cumulative value of AC feeder segment length, sequential order of cumulative value of tie switch quantity, and sequential order of cumulative value of energy storage access capacity. Then, write the candidate grid with the sequence number of one after sorting into the target microgrid grid planning result.

[0013] A microgrid grid planning system based on multi-objective optimization and scenario simulation is proposed. The system includes a grid construction module, a scenario deduction module, a pairing module, an identification module, and a planning output module. The network structure construction module is used to collect the initial access entity records, distributed power source records, energy storage access records, line records, and switch connection records of the park, and to perform corresponding organization on various records to generate an initial network structure diagram, partition table, and power table; The scenario simulation module is used to perform social simulation on the subsequent access locations based on the proposed main body type table, expansion timeline table and park main body replacement process, generate multiple main body replacement scenarios, and solve the new power landing point, power exchange direction, power supply restoration sequence and energy storage support location for each main body replacement scenario, forming a scenario result table. The matching module is used to perform position changes around the location of the interconnection switch, the location of the partition boundary and the location of the energy storage access in the initial grid diagram, generate candidate grid groups, and match each candidate grid with the scenario result table one by one to form a grid scenario comparison table. The identification module is used to perform power flow calculation, power transfer path calculation and recovery path calculation for each candidate grid in each main body replacement scenario, based on the grid scenario comparison table, to identify whether there are main wiring changes, zoning re-division and energy storage relocation, and to generate a locking record table. The planning output module is used to combine the locking record table to eliminate candidate grid structures that have undergone main wiring changes, zoning re-division, or energy storage relocation. Then, it performs construction investment calculations, power supply reliability calculations, distributed power source absorption calculations, and subsequent modification count calculations on the remaining candidate grid structures, and outputs the target microgrid grid structure planning results.

[0014] The technical effects and advantages of this invention are as follows: 1. This solution maps the main replacement scenario to the candidate grid structure one by one, and locks and identifies the main wiring changes, zoning re-division and energy storage relocation. It can eliminate grid structures with limited expansion direction in advance during the planning stage, and relatively suppress the dismantling and modification risks caused by subsequent main changes. 2. By converting the number of entities to be connected, the timing of the connection, and the replacement process into the new power landing points, power exchange directions, power restoration order, and energy storage support locations, subsequent expansion needs can be mapped to the grid structure level earlier, thereby improving the planning results' ability to accommodate subsequent changes. 3. By changing the locations of the tie switch, zone boundary, and energy storage access, and verifying each item in conjunction with the feeder path, tie path, and supplementary power path, the candidate grid selection can be based on the actual carrying capacity relationship of the AC distribution network, thereby relatively reducing the mismatch caused by judging solely based on capacity margin. 4. Perform local power replenishment, interconnection power transfer, and energy storage power replenishment calculations sequentially for the power loss zone, and backfill the required power according to the order of power restoration. This allows the grid evaluation to cover both normal load-bearing and fault recovery processes, thereby improving the rationality of the configuration of power transfer paths and energy storage support locations. Attached Figure Description

[0015] Figure 1 This is a flowchart outlining the method steps of the present invention; Figure 2 This is a schematic diagram of the system module structure of the present invention. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0017] Refer to the instruction manual appendix Figure 1-2 The microgrid network planning method based on multi-objective optimization and scenario simulation of the present invention includes: S1. Collect the initial access records of the park, distributed power source records, energy storage access records, line records and switch connection records, and perform corresponding sorting on various records to generate the initial network diagram, partition table and power table; This implementation method is used to organize the initial access entity records, distributed power source records, energy storage access records, line records, and switch connection records of the park into basic data that can be directly read in subsequent network structure simulations. During processing, the initial access entities, distributed power sources, and energy storage access points are first assigned to their corresponding line endpoints. Then, the power supply path from the power source access point to the load access point is traced along the line connection relationship. Zone boundaries are delineated based on disconnected switches. Subsequently, the injected power of the distributed power source, the charging and discharging power of the energy storage, and the power taken from the initial access entity are allocated to the corresponding zones, and the incoming power, outgoing power, and switching power of each zone are recorded. The initial access entity record of the park should at least include the entity number, access location number, active power demand, reactive power demand, and time period number. The distributed power source record should at least include the power source number, access location number, and injected power. The energy storage access record should at least include the energy storage number, access location number, charging power, and discharging power. The line record should at least include the line segment number, the first node number, the last node number, and the rated current value. The switch connection record should at least include the switch number, the line segment number, the connection direction, and the on / off status. This implementation process includes the following steps: S11 is used to write the initial access entities, distributed power sources, and energy storage access points into unique nodes respectively. During processing, the initial access entity records, distributed power source records, energy storage access records, line records, and switch connection records of the park are read first, and the access location numbers are matched with the line endpoint numbers in the line records one by one. The initial access entities are written into the load access nodes, distributed power sources are written into the power access nodes, and energy storage access points are written into the energy storage access nodes to obtain the object ownership results. When there are multiple objects in the same node, they are written into the node connection table in a fixed order of initial access entities, distributed power sources, and energy storage access points. The node connection table uses the node number and object number as index fields. When the access location number is missing, the writing of the current object is stopped, and the object number, missing field name, and source record number are written into the missing record. The node ownership sorting is performed again after the missing record is filled in. S12 is used to write the power supply path based on the node connection table and write the segment boundaries into the initial network diagram and partition table. During processing, the node connection table, line record, and switch connection record are read first. Taking the node where the power access point is located as the feeder starting point, the first and last nodes of the line are connected segment by segment according to the line segment number and the switch connection direction. When a switch with an open state is encountered, the connection of the current branch is stopped, and the nodes on both sides of the line segment where the open switch is located are written as the segment boundary. When a node that has been written into the current power supply path is encountered again during the connection process, the current connection is stopped, and the corresponding node is marked as a closed node. Then, the power supply path formed from the power access point to each load access point is written into the initial network diagram, the segment boundary is written into the partition table, and the nodes on both sides of the normally open tie switch are written into different partition numbers. When there are multiple subsequent line segments, the connection continues in the order of the line segment numbers. S13 is used to convert the node access power into the partition power result. During processing, the initial network diagram, node connection table, and partition table are read first. The distributed power injection power in each partition is accumulated item by item. The energy storage discharge power in each partition is subtracted from the power taken by the main access in the first phase. The energy storage charging power is subtracted from the distributed power injection power to obtain the net injection amount of the partition. Then, with the partition as a reference, the line power entering the partition is written as the incoming line power, the line power leaving the partition is written as the outgoing line power, and the line power transmitted across partitions through the tie switch is written as the switching power. These are written into the power table according to the partition number. When there is no distributed power record or energy storage access record in the partition, the corresponding injection power, charging power, and discharge power are written as zero and then the segmented calculation continues. Through the above processing, the first access object is first located at the node, then the node is used to trace the power supply path and segment boundary, and finally the power result is written from the path and partition relationship. Subsequent main body replacement scenarios, candidate network structure changes, power flow write-back and power transfer recovery can all directly read the initial network structure diagram, partition table and power table. In practical applications: For parks that have already connected office buildings, standard factory buildings, rooftop photovoltaics, and public energy storage in the first phase, the office buildings and standard factory buildings can be written into the load access node, the rooftop photovoltaics into the power access node, and the public energy storage into the energy storage access node. Then, the power supply path from the power access point to each load access point can be traced according to the feeder connection relationship, and the zone boundaries can be drawn according to the disconnection switch. Subsequently, the photovoltaic injection power, energy storage charging and discharging power, and main power extraction power are accumulated according to the zone to obtain the incoming power, outgoing power, and switching power of each zone, which can be used for subsequent grid planning.

[0018] S2. Based on the proposed main body type table, expansion timeline table and park main body replacement process, perform social simulation on subsequent access locations to generate multiple main body replacement scenarios. For each main body replacement scenario, solve the new power landing point, power exchange direction, power supply restoration sequence and energy storage support location to form a scenario result table. This implementation method converts the time-series access changes of the proposed main body into scenario results that can be directly read for subsequent grid changes and power flow calculations. During processing, firstly, based on the expansion timeline and the main body replacement process within the park, the proposed main bodies for each time period are written into the subsequent access locations, and the access establishment basis is checked item by item according to feeder margin, transformer margin, and interconnection switch path. Then, for each retained main body replacement scenario, the power supply path carrying capacity and zonal exchange relationship are calculated, and the new power landing point and power exchange direction are written out. Subsequently, the carrying capacity of local power replenishment, transfer power replenishment, and energy storage power replenishment is calculated around the power outage zone. Following the sequence, write down the order of power restoration and the location of energy storage support; finally, compare the results of each time period with the subsequent access locations item by item, delete invalid scenarios, merge resolvable scenarios, and obtain a scenario result table; the expansion sequence table should at least include the time period number, main body type number, number of access points, and access order; the park main body replacement process should at least include the order of entry, exit, and capacity expansion; the subsequent access locations should at least include the access location number, corresponding feeder node number, and corresponding partition number; the main body replacement scenario group uses the scenario number and time period number as a composite index field; this implementation process includes the following steps: S21 is used to write the proposed entities into the subsequent access locations according to time periods, and first eliminate scenarios that do not have the access foundation. During processing, the time period number, entity type number and access quantity in the expansion time sequence table are read first, and the proposed entities for each time period are written into the subsequent access locations one by one according to the time period order and access priority. When a subsequent access location corresponds to multiple proposed entities, they are written in the order of entity type number, without dismantling or modifying the subsequent access location number, only adding the entity number and scenario number. After writing, the new active power demand, new reactive power demand, distributed power injection amount and energy storage replenishment demand amount are written for each subsequent access location. Among them, the new active power demand and new reactive power demand come from the proposed entity type table, and the distributed power injection amount and energy storage replenishment demand amount come from the power field and energy storage field of the proposed entity. If the corresponding field does not exist, it is written as zero. Subsequently, the newly added active power demand is subtracted from the corresponding feeder margin, the newly added reactive power demand is subtracted from the corresponding transformer margin, the energy storage replenishment demand is deducted segment by segment from the corresponding tie switch path carrying capacity, the distributed power injection quantity is written to the access node, and then the reverse carrying capacity result of the feeder where the node is located is calculated back. If any of the four results is negative, the scenario number, negative value field name, and corresponding subsequent access location number are written to the mismatch scenario table. If none of the four results are negative, the scenario number and each subsequent access location are written to the reserved scenario table. The reserved scenario table is then rearranged in order of time period number, entry order, exit order, and capacity expansion order. If the previous items are the same, the subsequent items are compared. If all are the same, they are written in the order of scenario number to obtain the main replacement scenario group. If the number of accesses is missing in the expansion time sequence table, the current main writing is stopped, and the time period number and missing field name are written to the missing record. S22 is used to map the changes in the main access in the main replacement scenario group onto the AC feeder path, and write down the new power landing point and power exchange direction. During processing, first read the main replacement scenario group, the initial network diagram, and the correspondence between the subsequent access position and the feeder node. For each main replacement scenario, read the power supply path from the subsequent access position to the corresponding feeder node one by one. Then, subtract the current carrying capacity of each line segment in the path from the new active power demand and the new reactive power demand corresponding to the subsequent access position segment by segment. Each time the subtraction is performed, the line segment number and the subtraction result are written into the path capacity sequence. When the same subsequent access position corresponds to multiple reachable paths, multiple path capacity sequences are formed respectively. Subsequently, the path margin sequence formed by connecting adjacent partitions via tie switches is compared three times. First, the results of the first segment are compared. If the results of the first segment are the same, the results of the last segment are compared. If the results of the last segment are the same, the cumulative values ​​of the results of each segment are compared. If the cumulative values ​​of the results of each segment are the same, they are arranged in order of the line segment numbers contained in the path. After sorting, the power receiving node corresponding to the first path in the sorting is written as the new power landing point, and the power supply partition number corresponding to the path is written to the power receiving partition number as the power exchange direction. The scenario number, subsequent access location number, new power landing point and power exchange direction are written into the scenario intermediate table. When all the path margin sequences have negative values, the new power landing point is not written. Instead, the scenario number is written back to the mismatch scenario table and the path processing of the current subsequent access location is stopped. S23 is used to write the sequence of distributed power sources, interconnection power transfer, and energy storage support around the power loss zone, thereby obtaining the order of power restoration and the location of energy storage support. During processing, the power loss zone number, zone load, distributed power injection amount in the zone, power transfer of adjacent interconnection switch zones, and remaining discharge amount of each energy storage access location in the main replacement scenario are read first. The distributed power injection amount in the zone is subtracted from the zone load amount item by item. If the subtraction result is greater than zero, only the local replenishment amount with the same value as the zone load amount is written, and the remaining distributed power injection amount is left in the original zone and no longer written to the current power loss zone. If the subtraction result is less than or equal to zero, the distributed power injection amount is written as the local replenishment amount in full, and the uncovered part is written as the remaining demand amount. Then, the remaining demand amount is subtracted from the power transfer of adjacent interconnection switch zones item by item. Each time, only the power transfer replenishment amount not exceeding the current remaining demand amount is written. After writing one item, the remaining demand amount is updated until the interconnection switch zones are written item by item or the remaining demand amount is zero. If the remaining discharge amount is still not zero, subtract the remaining demand amount from the remaining discharge amount of each energy storage access point one by one. Write only the energy storage replenishment amount that does not exceed the current remaining demand amount each time, and write the energy storage access point number that undertakes the write as the energy storage support position. Finally, according to the writing order of local replenishment amount, transfer replenishment amount and energy storage replenishment amount, write the corresponding partition number as the power restoration sequence, write the energy storage access point number that actually undertakes the last segment of replenishment writing as the energy storage support position, and write the scenario number, power failure partition number, power restoration sequence and energy storage support position into the scenario intermediate table. If the remaining demand amount is still not zero after all replenishment sources have been written, write the scenario number, power failure partition number and remaining demand amount into the mismatch scenario table, and do not enter the subsequent scenario merging. S24 is used to compare the results of scenarios in each time period, delete conflicting scenarios, and merge duplicate scenarios to obtain a scenario result table that can be directly read for subsequent grid pairing. During processing, the newly added power landing point, power exchange direction, power restoration order, and energy storage support position in each subject replacement scenario are read first, and the same subsequent access position is compared item by item according to the time period number. When the newly added power landing point is written to the same node in two time periods, the same position count is incremented by one; when written to different nodes, the same position count remains unchanged. When the start and end partitions of the power exchange direction are opposite, the reverse count is incremented by one. The order of power restoration is obtained by subtracting the positions of the same power failure partition in two time periods, taking the absolute value, and accumulating it to obtain the position difference accumulation value. When the same energy storage access position number is written to the energy storage support position in two time periods, the repetition count is incremented by one. After completing the comparison of all time periods, a deletion mark is written for scenarios with zero same-position count and greater than zero reverse count, while retaining the original scenario number. A merge mark is written for scenarios with the same newly added power landing point and the same energy storage support location, and a new merged scenario number is generated. The original scenario number is written as a back-pointing record. For scenarios that are neither deleted nor merged, the original scenario number is directly retained. Finally, the retained scenario number, merged scenario number, corresponding subsequent access location number, newly added power landing point, power exchange direction, power restoration order, and energy storage support location are written into the scenario result table. When the time period result is missing, no comparison is performed, and the scenario number is directly written into the failure record to avoid reading empty fields in subsequent grid scenario pairing. Through the above processing, the access changes of the main body in each time period are first converted into feasible main body replacement scenarios, then into power supply path carrying results, partition exchange results and power failure recovery results, and finally converged into a scenario result table. Subsequent candidate grids only need to read the new power landing point, power exchange direction, power supply recovery sequence and energy storage support position item by item to continue to perform position change and power flow verification. In practical applications: For parks that will subsequently introduce cold chain warehousing, fast charging stations, and night shift production entities, the three types of entities can be first written into the cold chain access location, charging access location, and production access location according to the expansion sequence table. Then, the new active power demand, new reactive power demand, and energy storage replenishment demand are checked against the corresponding feeder margin, transformer margin, and interconnection switch path item by item. Scenarios that cannot be established are deleted, and after retaining the established scenarios, the power supply path of each subsequent access location is read. The power receiving node where the cold chain is located, the switching direction where the fast charging is located, the recovery priority of the night shift production and the corresponding energy storage support location are written down. Finally, a scenario result table that can be directly read for candidate grid structure changes is obtained.

[0019] S3. Based on the location of the interconnection switch, the location of the partition boundary and the location of the energy storage access in the initial grid diagram, perform location changes to generate candidate grid groups, and match each candidate grid with the scenario result table to form a grid scenario comparison table. This implementation method is used to translate the access changes in the scenario results table into actual changes in AC feeders, tie switches, zone boundaries, and energy storage access locations. It also filters out candidate grid structures that cannot meet the scenario requirements, thus providing directly readable grid scenario comparison results for subsequent power flow calculations, power transfer calculations, and recovery calculations. During processing, based on the initial grid diagram, position replacements are performed on the tie switch locations, zone boundary locations, and energy storage access locations, and the connection relationships after each replacement are written into a candidate connection table. Then, the newly added power landing points, power exchange directions, and energy storage support locations in the scenario results table are mapped item by item to the corresponding feeder paths, tie paths, and supplementary power paths in the candidate connection table. The rated current values ​​of each path segment and the line segment values ​​are then compared. The number of times each switch crosses and zone crosses is calculated, and candidate grid structures that cannot meet the path power requirements are removed. Finally, the remaining candidate grid structures are sorted in a fixed order, and the sorting results are written into the grid structure scenario comparison table along with the path results. The initial grid structure diagram should at least include the AC feeder segment number, the first node number, the last node number, the tie switch location number, the zone boundary location number, and the energy storage access location number. The scenario result table should at least include the scenario number, the subsequent access location number, the new power landing point, the power exchange direction, the order of power restoration, and the energy storage support location. The candidate grid structure group uses the candidate grid structure number as the index field, and the candidate connection table uses the candidate grid structure number and the scenario number as a combined index field. This implementation process includes the following steps: S31 is used to expand the initial network diagram into an enumerable candidate network and write the connection relationship after each position replacement into the candidate connection table. During processing, the starting node, ending node, tie switch position, partition boundary position and energy storage access position of the AC feeder segment in the initial network diagram are read first, and written into the original connection table according to the feeder connection order. The tie switch position, partition boundary position and energy storage access position only change within the number set given in the corresponding candidate position table, and no new positions are added outside the candidate position table. Subsequently, open-position replacement and closed-position replacement are performed for each tie switch position, in-line replacement and disconnection replacement are performed for each zone boundary position, and out-replacement replacement and in-replacement replacement are performed for each energy storage access position. After each replacement is completed, the AC feeder segments are traced segment by segment according to the first node, the last node and the connection direction in the original connection table to obtain the power supply path from the power access point to the load access point, the tie path formed by the tie switch between zones, and the supplementary power path from the energy storage access point to the target zone. The three types of paths, along with the node connection relationship after replacement, are written into the candidate connection table. When the same node appears again in the same candidate grid during the tracing process, the current path tracing is stopped and the corresponding node is marked as a closed node. When the path encounters a disconnect switch, the tracing is stopped. When the candidate position table lacks the tie switch position number, zone boundary position number or energy storage access position number, the current replacement is stopped and the candidate grid number and the missing field name are written into the missing record. S32 is used to check whether each candidate grid has the line conditions to support the scenario requirements based on the candidate connection table and the scenario result table, and write the available candidate grids into the reservation table. During processing, firstly, the power supply path, tie path and supplementary power path in the candidate connection table of each candidate grid in the candidate grid group are read one by one. The power supply path corresponds to the distributed power access point to the new power landing point, the tie path corresponds to the starting partition to the ending partition of the power exchange direction, and the supplementary power path corresponds to the energy storage support position to the power failure partition. Then, the path power demand value corresponding to the three types of paths is read from the scenario result table. The power supply path demand value is the access power corresponding to the new power landing point, the tie path demand value is the exchange power corresponding to the power exchange direction, and the supplementary power path demand value is the supplementary power corresponding to the energy storage support position. The rated current value of the line segment in each path is subtracted from the corresponding path power demand value segment by segment, and the subtraction result of each segment is written into the path verification record in the order of the line segment number. Subsequently, for each path, the number of line segments, the number of switch crossings, and the number of zone crossings are accumulated. The number of line segments is accumulated based on the number of line segments within the path, the number of switch crossings is accumulated based on the number of switch positions traversed in the path, and the number of zone crossings is accumulated based on the number of zone boundary positions crossed by the path. When the subtraction result of any line segment in any path is negative, the candidate grid number, scenario number, and the line segment number with the negative value are written into the elimination table. When none of the three types of paths have negative values, the candidate grid number, scenario number, the accumulated value of the number of path segments, the accumulated value of the number of switch crossings, and the accumulated value of the number of zone crossings, along with the corresponding feeder path, tie path, and supplementary power path, are written into the retention table. When the path power demand value is missing in the scenario result table, the subtraction is not performed, and the candidate grid number, scenario number, and missing field name are directly written into the failure record. S33 is used to assign a fixed order to the candidate grid structures to be retained under the same main body replacement scenario, and write the order and path results into the grid structure scenario comparison table. During processing, first, all candidate grid structures belonging to the same main body replacement scenario in the retention table are read according to the scenario number. For each candidate grid structure, the cumulative value of the number of path segments, the cumulative value of the number of switch crossings, and the cumulative value of the number of partition crossings are compared in turn. First, the cumulative value of the number of path segments is compared, and the smaller value is ranked first. If the cumulative value of the number of path segments is the same, the cumulative value of the number of switch crossings is compared, and the smaller value is ranked first. If the cumulative value of the number of switch crossings is the same, the cumulative value of the number of partition crossings is compared, and the smaller value is ranked first. If all three items are the same, they are arranged in order of candidate grid structure number. After sorting, the sorting order is written into a scenario order table, and the candidate grid structure number, scenario number, sorting sequence number in the scenario order table, as well as the power supply path, tie path, and supplementary power path in the retention table are written into the grid structure scenario comparison table one by one. When the retention table is empty under the same scenario, the scenario number is written into an empty candidate record, and sorting and comparison table writing are not performed again. Through the above processing, the initial grid diagram is first expanded into candidate grid groups, and then the load-bearing capacity of its power supply path, tie path and supplementary power path is checked item by item by the scenario result table. Candidate grids that cannot meet the path power demand value are eliminated before entering the power flow calculation. Candidate grids that can meet the path power demand value are written into the grid scenario comparison table in a fixed order. Subsequently, it is only necessary to read the candidate grid number and scenario number item by item to continue to perform power flow write-back, power transfer simulation and recovery simulation. In practical applications: For parks with simultaneous cold link access locations, fast charging access locations, and public energy storage access locations, the corresponding AC feeder segments, tie switch locations, zone boundary locations, and energy storage access locations can be read from the initial network diagram. Tie switch opening / closing replacement, zone boundary switching replacement, and energy storage removal / input replacement can be performed respectively to obtain multiple candidate connection tables. Then, the cold link access power from the scenario result table is written into the feeder path demand value, the fast charging zone exchange power is written into the tie path demand value, and the public energy storage supplementary power is written into the supplementary path demand value. The rated current value of each line segment is checked, and the number of path segments, switch crossings, and zone crossings are accumulated. Candidate network structures with insufficient capacity are deleted. Finally, the remaining candidate network structures are sorted sequentially by the accumulated value of the number of path segments, the accumulated value of the number of switch crossings, and the accumulated value of the number of zone crossings, creating a network scenario comparison table for subsequent network planning.

[0020] S4. For the grid structure scenario comparison table, perform power flow calculation, power transfer path calculation and recovery path calculation for each candidate grid structure in each main body replacement scenario, identify whether there are main wiring changes, partition re-division and energy storage relocation, and generate a locking record table. This implementation method is used to further calculate the feeder power allocation, interconnection transfer and energy storage replenishment of each candidate grid in each main replacement scenario after the candidate grid has been paired with the main replacement scenario, and to determine whether main wiring changes, zone re-division and energy storage relocation have occurred. During processing, the load, power supply and energy storage power are first written into the AC feeder nodes and written back segment by segment to obtain the scenario power flow table. Then, the interconnection transfer results and energy storage recovery results are written around the power outage zone. Finally, each result is checked against the initial grid diagram and written into the locking record table. This implementation process includes the following steps: S41 is used to write back the node power of the candidate grid in the main replacement scenario to the feeder head end to obtain the scenario power flow table. During processing, the candidate grid number, scenario number, feeder path, interconnection path and supplementary power path are read from the grid scenario comparison table. Then, according to the node order from the head end to the end of the AC feeder, the load power consumption, distributed power injection amount and energy storage charging and discharging amount are written to each node respectively. Subsequently, node power aggregation and line power allocation are performed segment by segment along the feeder, and the results of each segment are written back to the upstream nodes. When the power value at the head end of the feeder in this round is equal to the power value at the head end of the feeder in the previous round, the write-back stops and the node net injection value and line power are written to the scenario power flow table. When the path field is missing, the power flow write-back of the current candidate grid and the current scenario is stopped and a failure record is written. S42 is used to write the interconnection and transfer results around the power outage zone. During processing, the power outage zone number, the zone's required power, and the distributed power injection amount within the zone are read from the scenario power flow table. The local gap amount is obtained by subtracting the distributed power injection amount within the zone from the zone's required power. When the local gap amount is greater than zero, the line balance of the transfer path corresponding to each interconnection switch is read, deducted segment by segment, and written into a path balance string. Then, each path balance string is compared sequentially according to the first segment balance, the last segment balance, and the cumulative value of each segment balance, and the local gap amount is filled back line by line according to the obtained order. When the local gap amount is zero, the transfer writing stops, and the power outage zone number, interconnection switch number, transfer replenishment amount, and remaining gap amount are written into the transfer result table. When the transfer path is empty, the power outage zone number and the remaining gap amount are written into the transfer result table. S43 is used to continue writing energy storage recovery results for power outage zones that have not yet returned to zero after power transfer. During processing, the remaining gap, power restoration order, and energy storage support location in the power transfer result table are read first, and then the remaining discharge amount and power replenishment path of each energy storage access point are read. Subsequently, the remaining gap is subtracted from the line balance segment by segment along the power replenishment path to obtain the power replenishment balance string, and the energy storage replenishment amount is written to the power outage zone item by item according to the power restoration order. After writing, the line power is calculated back according to the order from the end to the beginning of the power replenishment path, and the connection direction and energy storage balance are checked item by item. If the line balance, connection direction, or energy storage balance is negative, the current power replenishment path writing result is deleted and the deletion reason is written; otherwise, the power outage zone number, energy storage access point number, energy storage replenishment amount, and remaining gap after power replenishment are written to the recovery result table. S44 is used to write the locking record table based on the scenario power flow table, transfer result table, and recovery result table. During processing, it first reads the feeder connection position, zone assignment position, and energy storage access position in the initial network diagram, and then reads the write results corresponding to the current candidate network number and the current scenario number in the scenario power flow table, transfer result table, and recovery result table. If the scenario write power after the feeder connection position is rewritten does not result in a negative value when subtracted from the rated current value of the line segment, the candidate network number, scenario number, feeder connection position number, and main wiring modification are written into the locking record table. If the order of power loss zones in the recovery result after the zone assignment position is rewritten is the same as the order of power restoration in the scenario result table, the candidate network number, scenario number, zone assignment position number, and zone redrawing are written into the locking record table. If the remaining gap after power replenishment is zero after the energy storage access position is rewritten, the candidate network number, scenario number, energy storage access position number, and energy storage relocation are written into the locking record table. If the numbers do not correspond, the current verification is stopped and a failure record is written. Through the above processing, the candidate grid first obtains the scenario power flow result, then the interconnection and power transfer result and the energy storage recovery result. Finally, the initial grid diagram is checked item by item to see if the feeder connection position, partition ownership position and energy storage access position need to be rewritten, so as to accurately write the candidate grid that does not meet the current main body replacement scenario into the locking record table. In practical applications: For parks where office, production, and cold chain zones coexist, the load, photovoltaic injection, and energy storage charging and discharging of each zone can be written into the AC feeder nodes and written back to obtain the scenario power flow table. Then, the local power supply, interconnection transfer, and energy storage power supply for the cold chain zone can be calculated in sequence. Finally, the power supply results are checked against the initial grid diagram. If the current scenario can only be satisfied after rewriting the feeder connection position, zone ownership position, or energy storage access position, the corresponding rewrite is written into the locking record table for subsequent candidate grid screening and further reading.

[0021] S5. Based on the locking record table, candidate grid structures that have undergone main wiring changes, zoning re-division, or energy storage relocation are eliminated. Then, construction investment calculation, power supply reliability calculation, distributed power source absorption calculation, and subsequent modification count calculation are performed on the remaining candidate grid structures, and the target microgrid grid structure planning results are output. This implementation method is used to eliminate, calculate, and sort candidate grid structures based on the existing locking records, so that the final grid structure planning results directly correspond to the actual retention schemes for AC feeders, tie switches, and energy storage access. During processing, firstly, candidate grid structures with main wiring modifications, zoning changes, or energy storage relocations are eliminated according to the locking record table, and the corresponding AC feeder segment tables, tie switch tables, and energy storage access tables for the remaining candidate grid structures are written into the construction investment table. Then, the power supply value, transfer value, energy storage value, and absorption value are calculated for each scenario of the retained candidate grid structures, and the calculation results for each scenario are sorted by site. The scenario numbers are summarized and written into the grid structure result table; finally, the grid structure result table and the construction input table are combined into a result string according to the candidate grid structure numbers, and multiple rounds of sorting are performed sequentially to write the target microgrid grid structure planning results; the lockout record table should at least include the candidate grid structure number, scenario number, main wiring modification items, zoning re-division items, and energy storage relocation items; the construction input table should at least include the candidate grid structure number, the cumulative value of AC feeder section length, the cumulative value of tie switch quantity, and the cumulative value of energy storage access capacity; the grid structure result table should at least include the candidate grid structure number, power supply value, transfer value, energy storage value, and absorption value; this implementation process includes the following steps: S51 is used to first eliminate candidate grid structures that cannot be retained, and write the construction volume of the retained candidate grid structures into the construction input table. During processing, it first reads the main wiring modification items, zoning rezoning items, and energy storage relocation items written by candidate grid structure number in the locking record table, and summarizes all scenario numbers under the same candidate grid structure number item by item. When any scenario writes a main wiring modification item, zoning rezoning item, or energy storage relocation item, a removal mark is written for that candidate grid structure, and the subsequent calculation of that candidate grid structure is stopped. When no three types of locking items are written in all scenarios, a retention mark is written for that candidate grid structure, and the construction input table is read. Retrieve the AC feeder segment table, tie switch table, and energy storage access table corresponding to the candidate grid structure; then, sum up the lengths of each line segment in the AC feeder segment table to obtain the cumulative AC feeder segment length value, sum up the number of tie switches in the tie switch table to obtain the cumulative tie switch quantity value, and sum up the energy storage access capacity in the energy storage access table to obtain the cumulative energy storage access capacity value. Write the candidate grid structure number and the three summation results into the construction investment table; if the lock record table lacks a candidate grid structure number, stop reading the current candidate grid structure and write the missing table name and missing field name into the failure record. S52 is used to convert the power supply acceptance results, interconnection and transfer results, energy storage replenishment results, and distributed power supply acceptance results of each retained candidate grid structure in the scenario of replacing all main structures into directly sortable result values. During processing, the retained candidate grid structure number in the construction investment table is read first, and then the scenario power flow table, transfer result table, and recovery result table are read for each scenario according to the candidate grid structure number. For each scenario, the number of restored power supply zones in the scenario power flow table is divided by the number of power outage zones and written as the scenario power supply value. When the number of power outage zones is not zero, the process is executed directly. The division process is as follows: when the number of lost power supply zones is zero and the number of restored power supply zones is zero, the scenario power supply value is written as one; when the number of lost power supply zones is zero and the number of restored power supply zones is not zero, the scenario power supply value is written as zero and an exception flag is written. Then, the number of power transfer completions in the power transfer result table is divided by the number of power transfer inputs and written as the scenario power transfer value. When the number of power transfer inputs is not zero, the division process is performed directly. When the number of power transfer inputs is zero and the number of power transfer completions is zero, the scenario power transfer value is written as one; when the number of power transfer inputs is zero and the number of power transfer completions is not zero, the scenario power transfer value is written as zero and an exception flag is written. Next, divide the completed power supply in the recovery result table by the requested power supply and write it as the scene energy storage value. If the requested power supply is not zero, perform the division directly. If both the requested power supply and the completed power supply are zero, write the scene energy storage value as one. If both the requested power supply and the completed power supply are zero, write the scene energy storage value as zero and add an exception flag. Then, divide the received power supply in the scene power flow table by the injected power supply and write it as the scene absorption value. If the injected power supply is not zero, perform the division directly. If both the injected power supply and the received power supply are zero, write the scene absorption value as zero. When the capacity is 1, and the injected power is zero while the received power is not zero, write the scenario absorption value as zero and write an anomaly mark. After all scenarios are written, sum the power supply value, power transfer value, energy storage value, and absorption value of each scenario in order of scenario number, and then divide them by the number of scenarios without failure marks to obtain the power supply value, power transfer value, energy storage value, and absorption value. Write the candidate grid number and the four results into the grid result table. When the number of scenarios is zero, stop the calculation of the current candidate grid result and write the candidate grid number into the empty scenario record. S53 is used to assign a unique ranking to the remaining candidate grids based on the grid structure result table and the construction investment table, and to write the first candidate grid as the target microgrid grid structure planning result. During processing, first, the power supply value, transfer value, energy storage value, and absorption value from the grid structure result table are combined with the cumulative values ​​of AC feeder segment length, tie switch quantity, and energy storage access capacity from the construction investment table to form a result string according to the candidate grid number. Then, any two result strings are sequentially sorted and compared: first, the power supply value is compared, with the larger value ranked first; if the power supply values ​​are the same, the transfer value is compared, with the larger value ranked first; if the transfer values ​​are the same, the energy storage value is compared, with the larger value ranked first; if the energy storage values ​​are the same, the absorption value is compared, with the larger value ranked first; if the absorption values ​​are the same, the AC feeder value is compared. The cumulative value of the segment length is used to rank the AC feeder segment lengths with smaller cumulative values. If the cumulative values ​​of the AC feeder segment lengths are the same, the cumulative value of the number of tie switches is compared, and the cumulative value of the number of tie switches is ranked first. If the cumulative value of the number of tie switches is the same, the cumulative value of the energy storage access capacity is compared, and the cumulative value of the energy storage access capacity is ranked first. If all seven results are the same, the candidate grids are ranked in order of their candidate grid numbers. After sorting, the candidate grid number with the serial number 1 and its corresponding AC feeder segment table, tie switch table, energy storage access table, power supply value, transfer value, energy storage value, and absorption value are written into the target microgrid grid planning results. If the grid result table or construction input table lacks a candidate grid number with the same name, the result string composition is not performed, and the candidate grid number and the missing table name are directly written into the failure record. Through the above processing, candidate grid structures with main wiring modifications, zoning re-divisions, or energy storage relocation are first eliminated. The remaining candidate grid structures are then converted item by item according to the scenario results to calculate the power supply acceptance, interconnection transfer, energy storage supplementation, and distributed power supply acceptance values. Finally, these values ​​are combined with the AC feeder section length, the number of interconnection switches, and the energy storage access capacity to enter the sorting process, thereby simultaneously reflecting the grid structure retention status and the operational acceptance status in the final planning output. In practical applications: For industrial parks that simultaneously have office zones, production zones, cold chain zones, and fast-supply zones, candidate grid structures with main wiring modifications, zoning redesigns, or energy storage relocations can be directly marked for removal. Then, for candidate grid structures without these three types of locking items, the AC feeder length, number of interconnecting switches, and energy storage access capacity are accumulated. Subsequently, for each main replacement scenario, the number of restored power supply zones, the number of power outage zones, the number of power transfer completions, the number of power transfer commissionings, the amount of power replenished, the amount of power replenished requested, and the amount of power received are read. For each scenario, the power supply value, transfer value, energy storage value, and absorption value are written out for the power supply and injected power. These values ​​are then summarized into the grid structure result table according to the scenario number. Finally, the grid structure result table and the construction input table are combined into a result string. The power supply value, transfer value, energy storage value, absorption value, cumulative value of AC feeder segment length, cumulative value of tie switch number, and cumulative value of energy storage access capacity are compared in sequence to obtain the candidate grid structure with the sequence number one. The corresponding AC feeder segment table, tie switch table, and energy storage access table are then written into the target microgrid grid structure planning results.

[0022] Furthermore, the present invention also includes a microgrid grid planning system based on multi-objective optimization and scenario simulation, the system comprising a grid construction module, a scenario deduction module, a pairing module, an identification module, and a planning output module: The network structure construction module is used to collect the initial access entity records, distributed power source records, energy storage access records, line records, and switch connection records of the park, and to perform corresponding organization on various records to generate an initial network structure diagram, partition table, and power table; The scenario simulation module is used to perform social simulation on the subsequent access locations based on the proposed main body type table, expansion timeline table and park main body replacement process, generate multiple main body replacement scenarios, and solve the new power landing point, power exchange direction, power supply restoration sequence and energy storage support location for each main body replacement scenario, forming a scenario result table. The matching module is used to perform position changes around the location of the interconnection switch, the location of the partition boundary and the location of the energy storage access in the initial grid diagram, generate candidate grid groups, and match each candidate grid with the scenario result table one by one to form a grid scenario comparison table. The identification module is used to perform power flow calculation, power transfer path calculation and recovery path calculation for each candidate grid in each main body replacement scenario, based on the grid scenario comparison table, to identify whether there are main wiring changes, zoning re-division and energy storage relocation, and to generate a locking record table. The planning output module is used to combine the locking record table to eliminate candidate grid structures that have undergone main wiring changes, zoning re-division, or energy storage relocation. Then, it performs construction investment calculations, power supply reliability calculations, distributed power source absorption calculations, and subsequent modification count calculations on the remaining candidate grid structures, and outputs the target microgrid grid structure planning results.

[0023] Working Principle: This scheme first organizes the relationships between the main entities, distributed power sources, energy storage, lines, and switches already connected in the first phase of the park into an initial network diagram, zoning table, and power table, clarifying the existing power supply paths, zoning boundaries, and power status of each zoning. Then, based on the type, number, and connection sequence of the main entities to be introduced later, it deduces different replacement scenarios for different entities, calculates where the new power will fall in each scenario, in which direction the power will be exchanged between zoning zones, in what order power should be restored after a power outage, and from where energy storage should be supported. On this basis, multiple sets of candidate networks are generated around the interconnection switches, zoning boundaries, and energy storage access locations, and each set of candidate networks is matched with each entity replacement scenario one by one. The power flow, interconnection transfer, and energy storage replenishment are calculated to determine which candidate networks need to modify the main wiring, re-divide zoning, or relocate energy storage. Finally, these candidate networks that cannot stably accommodate subsequent changes are eliminated, and the remaining candidate networks are compared in terms of power supply capacity, distributed power source absorption, and construction investment to select the target microgrid network planning result. For example, in a park where office buildings, standard factory buildings, rooftop photovoltaics, and public energy storage have already been connected in the first phase, and there are plans to connect cold chain storage, fast charging stations, and night shift production entities in the future, this solution will first map the existing lines, switches, photovoltaics, and energy storage to specific nodes and zones, and then simulate the power changes after cold chain connection, fast charging connection, and night shift production connection to determine which feeder these new entities will occupy, whether they need to transfer power to adjacent zones through tie switches, which zone should be prioritized for restoration in the event of a power outage, and from which access point the public energy storage should replenish power; then, the candidate grid structures formed by different tie switch opening and closing methods, zone boundary change methods, and energy storage access methods will be compared one by one, and those schemes that would require changes to the main wiring or re-division of zones if subsequent entities are connected will be eliminated, and finally, the grid structure scheme that can support the current operation of the park and accommodate changes in subsequent entities will be retained.

[0024] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A microgrid grid planning method based on multi-objective optimization and scenario simulation, characterized in that, include: S1. Collect the initial access records of the park, distributed power source records, energy storage access records, line records and switch connection records, and perform corresponding sorting on various records to generate the initial network diagram, partition table and power table; S2. Based on the proposed main body type table, expansion timeline table and park main body replacement process, perform social simulation on subsequent access locations to generate multiple main body replacement scenarios. For each main body replacement scenario, solve the new power landing point, power exchange direction, power supply restoration sequence and energy storage support location to form a scenario result table. S3. Based on the location of the interconnection switch, the location of the partition boundary and the location of the energy storage access in the initial grid diagram, perform location changes to generate candidate grid groups, and match each candidate grid with the scenario result table to form a grid scenario comparison table. S4. For the grid structure scenario comparison table, perform power flow calculation, power transfer path calculation and recovery path calculation for each candidate grid structure in each main body replacement scenario, identify whether there are main wiring changes, partition re-division and energy storage relocation, and generate a locking record table. S5. Based on the locking record table, candidate grid structures that have undergone main wiring changes, zoning re-division, or energy storage relocation are eliminated. Then, construction investment calculation, power supply reliability calculation, distributed power source absorption calculation, and subsequent modification count calculation are performed on the remaining candidate grid structures, and the target microgrid grid structure planning results are output.

2. The microgrid grid planning method based on multi-objective optimization and scenario simulation according to claim 1, characterized in that: S1 includes: S11. Perform node attribution sorting on the first phase access entity record, distributed power source record, energy storage access record, line record and switch connection record of the park, write the first phase access entity, distributed power source and energy storage access point into the corresponding line endpoint, and output the node connection table. S12. Based on the node connection table, perform feeder connection and segmentation for the beginning and end of the line and the switch connection direction. Write the power supply path formed from the power access point to each load access point and the segmentation boundary formed by the switch disconnection position into the initial network diagram and output the partition table. S13. Based on the initial network diagram and node connection table, perform segmented calculations on the distributed power injection power, energy storage charging and discharging power, and the power taken by the first phase of the connected main body, and write the incoming power, outgoing power, and switching power of each zone into the power table.

3. The microgrid grid planning method based on multi-objective optimization and scenario simulation according to claim 2, characterized in that: S2 includes: S21. Read the types and quantities of entities to be introduced in each time period according to the expansion time sequence table. Write the entities to be introduced in each time period into the subsequent access locations one by one. Subtract the new active power demand, new reactive power demand, distributed power injection amount and energy storage replenishment demand of each subsequent access location from the feeder margin, transformer margin and tie switch path in the initial network diagram. Write the subtraction result with negative values ​​into the mismatch scenario table. Write the subtraction result without negative values ​​into the reserved scenario table. Then rearrange the reserved scenario table according to the entry order, exit order and capacity expansion order in the process of replacing the park's entities. Output the entity replacement scenario group. S22. For each main replacement scenario in the main replacement scenario group, read the power supply path between the subsequent access location and the feeder node one by one. Subtract the current carrying capacity of each line segment in the path from the new active power demand and new reactive power demand corresponding to the subsequent access location segment by segment. Write the subtraction results of each line segment in the same path into a path capacity sequence according to the line order. Then sort the path capacity sequence formed by connecting adjacent partitions of each access location through the tie switch in the order of the first segment result, the last segment result, and the cumulative value of each segment result. Output the new power landing point and power exchange direction.

4. The microgrid grid planning method based on multi-objective optimization and scenario simulation according to claim 3, characterized in that: S2 also includes: S23. For the power loss zones in each main replacement scenario, first subtract the distributed power injection amount from the zone load amount one by one and write down the local replenishment amount. Then, subtract the power transfer of the part not covered by the local replenishment amount from the transfer power of the adjacent interconnection switch zone one by one and write down the transfer replenishment amount. Then, subtract the remaining discharge amount of each energy storage access location one by one from the part not covered by the transfer replenishment amount and write down the energy storage replenishment amount. Then, accumulate the local replenishment amount, transfer replenishment amount and energy storage replenishment amount according to the writing order until the power loss zone demand is zero, and output the order of power restoration and energy storage support location. S24. Compare the new power landing point, power exchange direction, power restoration order, and energy storage support location in each subject replacement scenario according to time period. Perform same-position counting on the new power landing point obtained by the same subsequent access location in different time periods, perform reverse counting on the power exchange direction, accumulate the position difference on the power restoration order, and accumulate the repetition count on the energy storage support location. Delete scenarios with zero same-position count and positive reverse count, merge scenarios with the same new power landing point and the same energy storage support location, and output the scenario result table.

5. The microgrid grid planning method based on multi-objective optimization and scenario simulation according to claim 4, characterized in that: S3 includes: S31. Write the starting node, ending node, tie switch position, zone boundary position, and energy storage access position of the AC feeder segment in the initial network diagram into an original connection table according to the feeder connection order. Perform on / off replacement on each tie switch position, perform parallel replacement or disconnection replacement on each zone boundary position, and perform removal replacement and removal replacement on each energy storage access position. After each replacement, follow up the AC feeder segment segment by segment according to the node connection relationship. Write the power supply path, tie path, and supplementary power path obtained by following up into a candidate connection table and output the candidate network group.

6. The microgrid grid planning method based on multi-objective optimization and scenario simulation according to claim 5, characterized in that: S3 also includes: S32. For each candidate grid in the candidate grid group, read the power supply path between the distributed power access point and the new power landing point, the interconnection path corresponding to the power exchange direction, and the supplementary power path corresponding to the energy storage support location according to the candidate connection table. Subtract the rated current value of the line segment in each path from the path power demand value in the scenario result table segment by segment. Add up the number of line segments, the number of switch crossings, and the number of zone crossings in each path. Write the candidate grid with a negative subtraction result into the elimination table. Write the candidate grid with a non-negative subtraction result, along with the accumulated value of the number of path segments, the accumulated value of the number of switch crossings, and the accumulated value of the number of zone crossings, into the retention table. S33. Based on the retention table, sort the candidate grid structures under the same subject replacement scenario in order of the cumulative value of the number of path segments, the cumulative value of the number of switch crossings, and the cumulative value of the number of partition crossings. Write the sorting results into a scenario ranking table, and write the candidate grid structure number, scenario number, power supply path, interconnection path and supplementary power supply path in the scenario ranking table into the grid structure scenario comparison table.

7. The microgrid network planning method based on multi-objective optimization and scenario simulation according to claim 6, characterized in that: S4 includes: S41. Match the candidate grid structures in the grid structure scenario comparison table with the main replacement scenario one by one. Write the load power consumption, distributed power injection, and energy storage charging and discharging into each node according to the node order from the beginning to the end of the AC feeder. Then, perform node power aggregation, line power distribution, and upstream write-back along the feeder segment by segment until the beginning power value obtained from the two write-backs of the same feeder is consistent. Output the scenario power flow table. S42. For the power outage zone in the scenario power flow table, first subtract the distributed power injection amount within the zone from the zone's required power to obtain the local gap amount. Then, for each tie switch, perform line margin deduction and path margin serial writing for each corresponding transfer path segment by segment. Compare the first segment margin, last segment margin, and full segment deduction of each path item by item in the order of first segment, then last segment, and then full segment. Select the transfer path in sequence and fill in the local gap amount. Output the transfer result table.

8. The microgrid grid planning method based on multi-objective optimization and scenario simulation according to claim 7, characterized in that: S4 also includes: S43. Based on the power transfer result table, for the non-zero power loss zone, the remaining discharge amount of each energy storage access point is deducted from the line balance segment by segment along the power replenishment path to obtain the power replenishment balance string. Then, the power replenishment balance string is written into the power loss zone item by item according to the order of power restoration. The line power, tie direction and energy storage balance after writing are reverse recalculated. The power replenishment path with negative line balance, reverse tie direction and negative energy storage balance after recalculation is deleted, and the restoration result table is output. S44. Based on the scenario power flow table, power transfer result table, and recovery result table, perform a check on the initial connection relationship and scenario satisfaction relationship for each candidate network structure. Write the changes in feeder connection positions and the scenario power after the change is included in the line rated range as main wiring changes. Write the changes in partition assignment positions and the power restoration order after the change is consistent with the scenario result table as partition redrawing. Write the changes in energy storage access positions and the power demand of the power-loss partition is zero after the change as energy storage relocation. Write the main wiring change record, partition redrawing record, and energy storage relocation record into the lock record table.

9. The microgrid grid planning method based on multi-objective optimization and scenario simulation according to claim 8, characterized in that: S5 includes: S51. Read the main wiring modification items, zoning re-division items and energy storage relocation items written in the lockout record table by candidate grid number one by one. Write a rejection mark for candidate grids written in any item. For candidate grids not written in any of the three items, retain the AC feeder section table, tie switch table and energy storage access table. Then, add up the AC feeder section length, tie switch number and energy storage access capacity respectively and write them into the construction investment table. S52. For each reserved candidate grid in the construction input table, divide the number of restored power supply zones in the scenario power flow table by the number of unsupplied power supply zones and write it as the scenario power supply value. Divide the number of power transfer completions in the power transfer result table by the number of power transfer inputs and write it as the scenario power transfer value. Divide the amount of power replenishment completed in the recovery result table by the amount of power replenishment requested and write it as the scenario energy storage value. Divide the amount of power received in the scenario power flow table by the amount of power injected and write it as the scenario absorption value. Then, sum up the scenario power supply value, scenario power transfer value, scenario energy storage value and scenario absorption value according to the scenario order and divide them by the number of scenarios, and write them into the grid result table. S53. Combine the power supply value, transfer value, energy storage value, and absorption value in the grid result table with the cumulative values ​​of AC feeder segment length, tie switch quantity, and energy storage access capacity in the construction investment table to form a result string according to the candidate grid number. For any two result strings, perform the following sorting in sequence: reverse order of power supply value, reverse order of transfer value, reverse order of energy storage value, reverse order of absorption value, sequential order of cumulative value of AC feeder segment length, sequential order of cumulative value of tie switch quantity, and sequential order of cumulative value of energy storage access capacity. Then, write the candidate grid with the sequence number of one after sorting into the target microgrid grid planning result.

10. A microgrid grid planning system based on multi-objective optimization and scenario simulation, used to implement the microgrid grid planning method based on multi-objective optimization and scenario simulation as described in any one of claims 1-9, the system comprising a grid construction module, a scenario deduction module, a pairing module, an identification module, and a planning output module, characterized in that: The network structure construction module is used to collect the initial access entity records, distributed power source records, energy storage access records, line records, and switch connection records of the park, and to perform corresponding organization on various records to generate an initial network structure diagram, partition table, and power table; The scenario simulation module is used to perform social simulation on the subsequent access locations based on the proposed main body type table, expansion timeline table and park main body replacement process, generate multiple main body replacement scenarios, and solve the new power landing point, power exchange direction, power supply restoration sequence and energy storage support location for each main body replacement scenario, forming a scenario result table. The matching module is used to perform position changes around the location of the interconnection switch, the location of the partition boundary and the location of the energy storage access in the initial grid diagram, generate candidate grid groups, and match each candidate grid with the scenario result table one by one to form a grid scenario comparison table. The identification module is used to perform power flow calculation, power transfer path calculation and recovery path calculation for each candidate grid in each main body replacement scenario, based on the grid scenario comparison table, to identify whether there are main wiring changes, zoning re-division and energy storage relocation, and to generate a locking record table. The planning output module is used to combine the locking record table to eliminate candidate grid structures that have undergone main wiring changes, zoning re-division, or energy storage relocation. Then, it performs construction investment calculations, power supply reliability calculations, distributed power source absorption calculations, and subsequent modification count calculations on the remaining candidate grid structures, and outputs the target microgrid grid structure planning results.

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