A power distribution network load dispatching system and method

Abstract

The application provides a power distribution network load scheduling system and method, which extracts fault feature information and establishes a fault mapping table according to historical load section data in historical operation data, realizes rapid positioning and identification of faults, simplifies a judgment process, and improves the reaction speed when a line power supply fails; when a node power supply fails, corresponding fault feature information is obtained according to real-time load section data at the node, and the corresponding fault type and the average fault maintenance time are obtained by searching the fault mapping table; load scheduling is performed according to the fault type, the average fault maintenance time and the load level, the influence of power failure is marginalized, the power failure loss is reduced, and the reliability and economy of power distribution network operation are improved.

Description

Technical Field

[0001] This invention belongs to the field of distribution network load dispatch automation, and particularly relates to load dispatch methods and systems when there are line faults at distribution network nodes. Background Technology

[0002] In the daily operation of the power distribution network, power failures often occur at nodes in the network, causing the loads connected to the node lines to lose power. In order to improve the reliability of power supply and avoid serious impacts or accidents caused by power outages, it is necessary to transfer the loads on the node lines to other power sources that can supply power normally.

[0003] The existing load dispatching method simply executes the preset dispatching scheme when a node fault is detected, without considering the specific type of node fault. This one-size-fits-all dispatching method cannot adapt to the increasingly complex distribution network environment. In particular, with more and more distributed power sources being connected to the grid, there are more choices for load transfer methods. Dispatching according to the original preset method often leads to secondary accidents due to dispatching conflicts, causing greater impact.

[0004] In addition, during the load dispatching process, the loads are usually not classified or the classification is too simple. The automatic dispatching using the preset scheme can only be applied to a single scenario and cannot be adapted to a large-scale power distribution network where multiple load types coexist.

[0005] For example, the invention patent application with publication number CN114977171A provides a method and device for load transfer in a distribution network. It discloses a method for rapid load transfer of a single line, a single bus, or a single substation based on a preset transfer strategy. Although this scheduling method can solve the problem of automatic load transfer in some networks, its control accuracy and applicability still need to be improved.

[0006] Therefore, in response to the above problems, it is urgent to solve the problem of how to develop a distribution network load dispatching system and method with wide applicability and high reliability. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and propose a power distribution network load dispatching system and method. This system can accurately identify the fault type based on fault information and perform load dispatching based on the fault type, average fault repair time, and load level. This will marginalize the impact of power outages, reduce power outage losses, and improve the reliability and economy of power distribution network operation.

[0008] This invention provides a method for load dispatching in a power distribution network, comprising the following steps:

[0009] S1: Extract historical load section data when a node experiences a power failure from the historical operation data of the distribution network, and establish a fault mapping table based on the mapping relationship between the fault characteristic information of the historical load section data and the final determined fault type in the history;

[0010] S2: Calculate the average repair time for the fault type based on the historical fault type final determination;

[0011] S3: Real-time acquisition of operation data of each node in the distribution network. When a power failure occurs at a node, the corresponding fault characteristic information is obtained based on the real-time load section data at that node, and the corresponding fault type and the average repair time of the fault are obtained by looking up the fault mapping table.

[0012] S4: Determine the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault.

[0013] Preferably, in step S4, determining the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault specifically includes:

[0014] Once the location of the faulty node is determined, and the load at the faulty node is identified as a critical load, further determination is made based on the determined fault type and the corresponding average maintenance time:

[0015] If it is a short-term fault, the node is first switched to the backup power line, and then the load rate and bus voltage of the backup power line are checked. If the load rate and bus voltage of the backup power line are both within the preset range, the dispatching operation is stopped.

[0016] If the load rate or bus voltage of the backup power line is not within the preset range, calculate the first overload of the backup power line. At the same time, use a heuristic algorithm to traverse the first unload of the lines of the two types of important load nodes around the node. If there is a line whose first unload is greater than or equal to the first overload, switch the load corresponding to the first overload to the line with the first unload, and the scheduling operation is stopped. If there is no line whose first unload is greater than or equal to the first overload, obtain the sorting of the first unload of the lines of the two types of important load nodes around the node according to the traversal results. If the sum of all the first unloads in the sorting is greater than or equal to the first overload, split and switch the load corresponding to the first overload to each line with the corresponding first unload according to the sorting of the first unload, and the scheduling operation is stopped.

[0017] Preferably, step S4 further includes:

[0018] If the sum of all first empty loads in the surrounding Class II important load node lines is less than the first overload, the surrounding Class II important load node line with the highest first empty load is used as the center. A heuristic algorithm is used to traverse the second empty loads of the surrounding Class III load node lines, and the difference between the first overload and the highest-ranked first empty load is calculated as the second overload. If there is a single line whose second empty load is greater than or equal to the second overload, the load corresponding to the first overload is first switched to the line with the highest-ranked first empty load, and then the load corresponding to the second overload is switched to the line with the second empty load, and the scheduling operation is terminated. If there is no single line whose second empty load is greater than or equal to the second overload, the ranking of the second empty loads of the surrounding Class III load node lines is obtained according to the traversal results. When the sum of the second empty loads is greater than or equal to the second overload, the load corresponding to the first overload is first switched to the line with the highest-ranked first empty load, and then the load corresponding to the second overload is split and switched to each line with the corresponding second empty load according to the second empty load ranking, and the scheduling operation is terminated.

[0019] If the sum of all second-order unloaded loads in the three types of load nodes in the surrounding area is less than the second-order overload, then the difference between the second-order overload and the highest-ranked second-order unload is calculated as the third-order overload. Based on the second-order unload, the load corresponding to the first-order overload is first switched to the line with the highest-ranked first-order unload, then the load corresponding to the second-order overload is switched to the line with the highest-ranked second-order unload, and the load corresponding to the third-order overload is cut off in the line with the highest-ranked second-order unload, and the scheduling operation is terminated.

[0020] Preferably, step S4 further includes:

[0021] In the case of a long-term fault, the node is first switched to the backup power line. Then, the load rate and bus voltage of the backup power line are checked. If the load rate and bus voltage of the backup power line are both within the preset range, the dispatching operation is stopped. If the load rate or bus voltage of the backup power line is not within the preset range, the first overload of the backup power line is calculated, and the load utilization rate of the backup power line is obtained. The load corresponding to the first overload is cut off according to the load utilization rate. Then, the mobile substation is dispatched to connect to the faulty node line, and the power supply is switched to the mobile substation to restore the power supply of the cut-off load.

[0022] Preferably, in step S4, determining the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault specifically includes:

[0023] Once the location of the faulty node is determined, and the load at the faulty node is identified as a Class II critical load, further determination is made based on the determined fault type and the corresponding average maintenance time:

[0024] If the fault is short-term, obtain the first load on the line connected to the node, and use a heuristic algorithm to traverse the third unloaded load of the lines of the two types of important load nodes around the node. If there is a line whose third unloaded load is greater than or equal to the first load, then switch the load connected to the line connected to the node to the line with the third unloaded load, and the scheduling operation is terminated. If there is no line whose third unloaded load is greater than or equal to the first load, then according to the traversal results, obtain the sorting of the third unloaded loads of the lines of the two types of important load nodes around the node. If the sum of all the third unloaded loads in the sorting is greater than or equal to the first load, then split and switch the connected load according to the sorting of the third unloaded loads to the lines with the corresponding third unloaded loads, and the scheduling operation is terminated.

[0025] Preferably, step S4 further includes:

[0026] If the sum of all third-order unloaded quantities in the surrounding Class II important load node lines is less than the first-order unloaded quantity, take the surrounding Class II important load node line with the highest third-order unloaded quantity as the center, use a heuristic algorithm to traverse the surrounding Class III load node lines with the fourth-order unloaded quantity, and calculate the difference between the first-order unloaded quantity and the highest-order third-order unloaded quantity as the fourth overload quantity.

[0027] If there exists a single line whose fourth empty load is greater than or equal to its fourth overload, the first load on that node's line is first switched to the line with the highest-ranked third empty load, and then the load corresponding to the fourth overload is switched to the line with the fourth empty load, and the scheduling operation is terminated. If there is no single line whose fourth empty load is greater than or equal to its fourth overload, the fourth empty load ranking of the surrounding three types of load nodes is obtained based on the traversal results. When the sum of all fourth empty loads in the ranking is greater than or equal to the fourth overload, the first load on that node's line is first switched to the line with the highest-ranked third empty load, and then the load corresponding to the fourth overload is split and switched to each line with the corresponding fourth empty load according to the fourth empty load ranking, and the scheduling operation is terminated.

[0028] If the sum of all fourth unloaded quantities in the three types of load nodes in the surrounding area is less than the fourth overload, then the difference between the fourth overload and the fourth unload with the highest ranking is calculated as the fifth overload. According to the ranking of the fourth unload, the first load on the node line is first switched to the line with the third highest unload. Then the load corresponding to the fourth overload is switched to the line with the fourth highest unload. The load corresponding to the fourth overload is then cut off in the line with the fourth highest unload, and the dispatching operation is terminated.

[0029] Preferably, step S4 further includes:

[0030] If the fault is prolonged, the load connected to the node should be disconnected first, and a mobile substation should be dispatched to connect to the faulty node's line as soon as possible. The power supply should be switched to the mobile substation to restore the power supply to the disconnected load.

[0031] Preferably, in step S4, determining the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault specifically includes:

[0032] Obtain the location of the fault node. When it is determined that the load at the fault node is a Class III load, obtain the second load quantity of the line connected to the node. Use a heuristic algorithm to traverse the fifth unload quantity of the lines of Class III load nodes around the node. If there is a single line whose fifth unload quantity is greater than or equal to the second load quantity, then switch the load connected to the line of the node to the line with the fifth unload quantity, and the scheduling operation is terminated.

[0033] If there is no single line whose fifth unloaded quantity is greater than or equal to the second load quantity, then based on the traversal results, obtain the ranking of the fifth unloaded quantities of the three types of load nodes in the surrounding area and the ranking of the load utilization rate of the faulty node line, switch the corresponding load to the line corresponding to the fifth unloaded quantity with the highest ranking, then cut off the excess load, and the scheduling operation is terminated.

[0034] Preferably, in step S1, establishing a fault mapping table based on the mapping relationship between fault characteristic information of historical load section data and the historically determined fault types specifically includes:

[0035] Extract bus and outgoing line currents, low-voltage side switch status, fuse status, and the fault type finally determined and uploaded by maintenance personnel from historical load section data. Perform Fourier transform on the bus and outgoing line currents to obtain current waveforms containing Nth harmonics. Combine the open / closed status of the low-voltage switch and the status of the line fuse at the time of the fault to establish a fault mapping table corresponding to the fault type.

[0036] To address the aforementioned problems, this invention also provides a power distribution network load dispatching system, which specifically includes: a sensor unit, a database, a control center, and an execution unit;

[0037] The sensor unit is responsible for collecting real-time operating data from each node of the power distribution network and storing it in the database;

[0038] The database also stores historical operation data of the distribution network. Historical load section data when a node experiences a power failure is extracted from the historical operation data of the distribution network. A fault mapping table is established based on the mapping relationship between the fault characteristic information of the historical load section data and the historical final determined fault type. The average maintenance time of the fault type is calculated based on the historical final determined fault type.

[0039] When a power failure occurs at a node, the control center reads the real-time load profile data of that node from the database, extracts the corresponding fault feature information, and looks up the fault mapping table to obtain the corresponding fault type and the average repair time of the fault. Then, based on the load level, fault type, and average repair time of the fault node, it determines the load scheduling method at the fault node and generates control commands to send to the execution unit.

[0040] The execution unit includes a switching switch, which is used to receive control commands sent by the control center to perform opening and closing operations in order to regulate the load.

[0041] The beneficial effects of this invention are as follows: 1. First, by combining the current transformation waveform, switch and fuse status and other information in the cross-sectional data, especially by using the harmonic waveform expanded in the Fourier transform of the current data to jointly determine the fault type, the fault is accurately defined, and a fault relationship mapping table is established to facilitate the rapid location and identification of the fault, simplify the judgment process, and improve the response speed when the line power supply is faulty.

[0042] 2. When scheduling loads, the load scheduling method is determined by combining the average repair time of faults based on the fault type. This is more in line with the actual scenario, the scheduling method is more reasonable, and the applicability of the system and the utilization rate of equipment are improved.

[0043] 3. During load dispatching, a heuristic algorithm is used to quickly obtain available transfer lines, and multiple transfer methods are adopted to prioritize the restoration of power supply to important loads, marginalizing the impact of power outages, reducing power outage losses, and improving the reliability and economy of distribution network operation. Attached Figure Description

[0044] Figure 1 This is a flowchart illustrating the steps of a power distribution network load dispatching method.

[0045] Figure 2 This is a control principle diagram of a power distribution network load dispatching system. Detailed Implementation

[0046] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0047] This invention provides a method for load dispatching in a power distribution network, such as... Figure 1 As shown, the following steps are taken:

[0048] S1: Extract historical load section data when a node experiences a power failure from the historical operation data of the distribution network, and establish a fault mapping table based on the mapping relationship between the fault characteristic information of the historical load section data and the final determined fault type in the history;

[0049] S2: Calculate the average repair time for the fault type based on the historical fault type final determination;

[0050] S3: Real-time acquisition of operation data of each node in the distribution network. When a power failure occurs at a node, the corresponding fault characteristic information is obtained based on the real-time load section data at that node, and the corresponding fault type and the average repair time of the fault are obtained by looking up the fault mapping table.

[0051] S4: Determine the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault.

[0052] Preferably, in step S4, determining the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault specifically includes:

[0053] Once the location of the faulty node is determined, and the load at the faulty node is identified as a critical load, further determination is made based on the determined fault type and the corresponding average maintenance time:

[0054] If it is a short-term fault, the node is first switched to the backup power line, and then the load rate and bus voltage of the backup power line are checked. If the load rate and bus voltage of the backup power line are both within the preset range, the dispatching operation is stopped.

[0055] If the load rate or bus voltage of the backup power line is not within the preset range, calculate the first overload of the backup power line. At the same time, use a heuristic algorithm to traverse the first unload of the lines of the two types of important load nodes around the node. If there is a line whose first unload is greater than or equal to the first overload, switch the load corresponding to the first overload to the line with the first unload, and the scheduling operation is stopped. If there is no line whose first unload is greater than or equal to the first overload, obtain the sorting of the first unload of the lines of the two types of important load nodes around the node according to the traversal results. If the sum of all the first unloads in the sorting is greater than or equal to the first overload, split and switch the load corresponding to the first overload to each line with the corresponding first unload according to the sorting of the first unload, and the scheduling operation is stopped.

[0056] The short-term fault is a fault type whose average repair time is less than a preset threshold.

[0057] Preferably, step S4 further includes:

[0058] If the sum of all first empty loads in the surrounding Class II important load node lines is less than the first overload, the surrounding Class II important load node line with the highest first empty load is used as the center. A heuristic algorithm is used to traverse the second empty loads of the surrounding Class III load node lines, and the difference between the first overload and the highest-ranked first empty load is calculated as the second overload. If there is a single line whose second empty load is greater than or equal to the second overload, the load corresponding to the first overload is first switched to the line with the highest-ranked first empty load, and then the load corresponding to the second overload is switched to the line with the second empty load, and the scheduling operation is terminated. If there is no single line whose second empty load is greater than or equal to the second overload, the ranking of the second empty loads of the surrounding Class III load node lines is obtained according to the traversal results. When the sum of the second empty loads is greater than or equal to the second overload, the load corresponding to the first overload is first switched to the line with the highest-ranked first empty load, and then the load corresponding to the second overload is split and switched to each line with the corresponding second empty load according to the second empty load ranking, and the scheduling operation is terminated.

[0059] If the sum of all second-order unloaded loads in the three types of load nodes in the surrounding area is less than the second-order overload, then the difference between the second-order overload and the highest-ranked second-order unload is calculated as the third-order overload. Based on the second-order unload, the load corresponding to the first-order overload is first switched to the line with the highest-ranked first-order unload, then the load corresponding to the second-order overload is switched to the line with the highest-ranked second-order unload, and the load corresponding to the third-order overload is cut off in the line with the highest-ranked second-order unload, and the scheduling operation is terminated.

[0060] Specifically, disconnecting the load corresponding to the third overload in the line with the highest second-highest unload capacity may include:

[0061] Based on historical operating data of the distribution network, the average daily operating time of the load on the line with the second highest no-load capacity is calculated, and the average daily operating time is ranked. Loads are then cut off in ascending order until the total amount of loads cut off is greater than or equal to the load corresponding to the third overload capacity.

[0062] Among them, R 日均 t represents the average daily operating time of the load. i Let i be the corresponding daily running length, i = 1, 2, ... 365;

[0063] Preferably, step S4 further includes:

[0064] In the case of a long-term fault, the node is first switched to the backup power line. Then, the load rate and bus voltage of the backup power line are checked. If the load rate and bus voltage of the backup power line are both within the preset range, the dispatching operation is stopped. If the load rate or bus voltage of the backup power line is not within the preset range, the first overload of the backup power line is calculated, and the load utilization rate of the backup power line is obtained. The load corresponding to the first overload is cut off according to the load utilization rate. Then, the mobile substation is dispatched to connect to the faulty node line, and the power supply is switched to the mobile substation to restore the power supply of the cut-off load.

[0065] Specifically, the long-term fault is a fault type whose average repair time is greater than or equal to a preset threshold;

[0066] The step of obtaining the load utilization ranking in the backup power line and disconnecting the load corresponding to the first overload based on the load utilization ranking may include:

[0067] Based on the historical operation data of the distribution network, the historical annual utilization rate of the loads on the standby power lines is statistically analyzed, and the historical annual utilization rate is ranked. The loads are then cut off in order from low to high until the total amount of the cut-off loads is greater than or equal to the load corresponding to the first overload.

[0068] Among them, R η The load's historical annual utilization rate is given by t, where t is the total annual operating time of the load, and T is the length of one year.

[0069] Preferably, in step S4, determining the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault specifically includes:

[0070] Once the location of the faulty node is determined, and the load at the faulty node is identified as a Class II critical load, further determination is made based on the determined fault type and the corresponding average maintenance time:

[0071] If the fault is short-term, obtain the first load on the line connected to the node, and use a heuristic algorithm to traverse the third unloaded load of the lines of the two types of important load nodes around the node. If there is a line whose third unloaded load is greater than or equal to the first load, then switch the load connected to the line connected to the node to the line with the third unloaded load, and the scheduling operation is terminated. If there is no line whose third unloaded load is greater than or equal to the first load, then according to the traversal results, obtain the sorting of the third unloaded loads of the lines of the two types of important load nodes around the node. If the sum of all the third unloaded loads in the sorting is greater than or equal to the first load, then split and switch the connected load according to the sorting of the third unloaded loads to the lines with the corresponding third unloaded loads, and the scheduling operation is terminated.

[0072] Preferably, step S4 further includes:

[0073] If the sum of all third-order unloaded quantities in the surrounding Class II important load node lines is less than the first-order unloaded quantity, take the surrounding Class II important load node line with the highest third-order unloaded quantity as the center, use a heuristic algorithm to traverse the surrounding Class III load node lines with the fourth-order unloaded quantity, and calculate the difference between the first-order unloaded quantity and the highest-order third-order unloaded quantity as the fourth overload quantity.

[0074] If there is a single line whose fourth empty load is greater than or equal to the fourth overload, the first load of the node line is first switched to the line with the highest third empty load, and then the load corresponding to the fourth overload is switched to the line with the fourth empty load, and the scheduling operation is stopped.

[0075] If there is no single line whose fourth empty load is greater than or equal to the fourth overload, then based on the traversal results, the fourth empty load of the surrounding three types of load nodes is sorted. When the sum of all fourth empty loads in the sort is greater than or equal to the fourth overload, the first load of the node line is first switched to the line with the highest third empty load. Then, the load corresponding to the fourth overload is split and switched to each line with the corresponding fourth empty load according to the fourth empty load sort. The scheduling operation is then terminated.

[0076] If the sum of all fourth unloaded quantities in the three types of load nodes in the surrounding area is less than the fourth overload, then the difference between the fourth overload and the fourth unload with the highest ranking is calculated as the fifth overload. According to the ranking of the fourth unload, the first load on the node line is first switched to the line with the third highest unload. Then the load corresponding to the fourth overload is switched to the line with the fourth highest unload. The load corresponding to the fourth overload is then cut off in the line with the fourth highest unload, and the dispatching operation is terminated.

[0077] Preferably, step S4 further includes:

[0078] If the fault is prolonged, the load connected to the node should be disconnected first, and a mobile substation should be dispatched to connect to the faulty node's line as soon as possible. The power supply should be switched to the mobile substation to restore the power supply to the disconnected load.

[0079] Preferably, if a long-term fault is confirmed, the dispatch time of the mobile substation is also confirmed. If the dispatch time of the mobile substation is less than or equal to the first preset time, the load attached to the node is first disconnected, and the mobile substation is dispatched to connect to the fault node line as soon as possible, switching to the mobile substation for power supply and restoring the power supply of the disconnected load.

[0080] If it is confirmed that the dispatching time of the mobile substation is longer than the first preset time, the first load of the line attached to the node is obtained, and the third unloaded load of the lines of the two types of important load nodes around the node is traversed using a heuristic algorithm. If there is a line whose third unloaded load is greater than or equal to the first load, the load attached to the line of the node is switched to the line with the third unloaded load, and the dispatching operation is terminated.

[0081] If there is no single line whose third empty load is greater than or equal to the first load, then based on the traversal results, obtain the ranking of the third empty load of the surrounding second-class important load nodes and the ranking of the load utilization rate of the faulty node line, switch the corresponding load to the line corresponding to the highest third empty load in the ranking, and stop the scheduling operation.

[0082] Specifically, the step of switching the corresponding load to the line corresponding to the third highest unloaded quantity in the ranking may include: cutting off loads in order of load utilization from low to high until the total amount of loads cut off is greater than or equal to the amount of load corresponding to the third highest unloaded quantity in the ranking.

[0083] Preferably, in step S4, determining the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault specifically includes:

[0084] Obtain the location of the fault node. When it is determined that the load at the fault node is a Class III load, obtain the second load quantity of the line connected to the node. Use a heuristic algorithm to traverse the fifth unload quantity of the lines of Class III load nodes around the node. If there is a single line whose fifth unload quantity is greater than or equal to the second load quantity, then switch the load connected to the line of the node to the line with the fifth unload quantity, and the scheduling operation is terminated.

[0085] If there is no single line whose fifth empty load is greater than or equal to the second load, then based on the traversal results, obtain the ranking of the fifth empty load of the three types of load nodes in the surrounding area and the ranking of the load utilization rate of the faulty node line, switch the corresponding load to the line corresponding to the fifth empty load with the highest ranking, then cut off the excess load, and the scheduling operation is terminated.

[0086] Specifically, the step of switching the corresponding load to the line corresponding to the fifth highest unloaded quantity in the ranking may include: cutting off loads in order of load utilization from low to high until the total amount of loads cut off is greater than or equal to the load corresponding to the fifth highest unloaded quantity in the ranking.

[0087] Preferably, for load dispatching operations performed when a node experiences a power failure, the load dispatching operations are restored according to the operation sequence after a second preset time has elapsed since the fault was recovered, and the power supply to the load is restored.

[0088] Preferably, in step S1, establishing a fault mapping table based on the mapping relationship between fault characteristic information of historical load section data and the historically determined fault types specifically includes:

[0089] Extract bus and outgoing line currents, low-voltage side switch status, fuse status, and the fault type finally determined and uploaded by maintenance personnel from historical load section data. Perform Fourier transform on the bus and outgoing line currents to obtain current waveforms containing Nth harmonics. Combine the open / closed status of the low-voltage switch and the status of the line fuse at the time of the fault to establish a fault mapping table corresponding to the fault type.

[0090] Specifically, since some types of fault current waveforms are similar, differing only in harmonic components, such as higher-order harmonic components in frequency and amplitude, fault types based on N-order harmonics can more accurately reflect the specific fault type. Preferably, N is selected as a harmonic within the 10th order.

[0091] To address the aforementioned problems, this invention also provides a power distribution network load dispatching system, such as... Figure 2 As shown, the load dispatching system specifically includes: a sensor unit, a database, a control center, and an execution unit;

[0092] The sensor unit is responsible for collecting real-time operating data from each node of the power distribution network and storing it in the database;

[0093] The database also stores historical operation data of the distribution network. Historical load section data when a node experiences a power failure is extracted from the historical operation data of the distribution network. A fault mapping table is established based on the mapping relationship between the fault characteristic information of the historical load section data and the historical final determined fault type. The average maintenance time of the fault type is calculated based on the historical final determined fault type.

[0094] When a power failure occurs at a node, the control center reads the real-time load profile data of that node from the database, extracts the corresponding fault feature information, and looks up the fault mapping table to obtain the corresponding fault type and the average repair time of the fault. Then, based on the load level, fault type, and average repair time of the fault node, it determines the load scheduling method at the fault node and generates control commands to send to the execution unit.

[0095] The execution unit includes a switching switch, which is used to receive control commands sent by the control center to perform opening and closing operations in order to regulate the load.

[0096] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, ROM, RAM, etc.

[0097] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for load dispatching in a distribution network, characterized in that, The following steps are adopted: S1: Extract historical load section data when a node experiences a power failure from the historical operation data of the distribution network, and establish a fault mapping table based on the mapping relationship between the fault characteristic information of the historical load section data and the final determined fault type in the history; S2: Calculate the average repair time for the fault type based on the historical fault type final determination; S3: Real-time acquisition of operation data of each node in the distribution network. When a power failure occurs at a node, the corresponding fault characteristic information is obtained based on the real-time load section data at that node, and the corresponding fault type and the average repair time of the fault are obtained by looking up the fault mapping table. S4: Determine the load scheduling method at the faulty node based on the load level, fault type, and average repair time of the fault. Specifically, the method for determining the load scheduling at the faulty node includes: Once the location of the faulty node is determined, and the load at the faulty node is identified as a critical load, further determination is made based on the determined fault type and the corresponding average maintenance time: If it is a short-term fault, the faulty node is first switched to the backup power line, and then the load rate and bus voltage of the backup power line are detected. If the load rate and bus voltage of the backup power line are both within the preset range, the scheduling operation is stopped. If the load rate or bus voltage of the backup power line is not within the preset range, the first overload of the backup power line is calculated, and at the same time, a heuristic algorithm is used to traverse the first no-load of the two types of important load nodes around the faulty node. If it is a long-term fault, first switch the faulty node to the backup power line, then check the load rate and bus voltage of the backup power line. If the load rate and bus voltage of the backup power line are both within the preset range, the dispatching operation is stopped. If the load rate or bus voltage of the backup power line is not within the preset range, calculate the first overload of the backup power line and obtain the load utilization ranking of the backup power line. According to the load utilization ranking, cut off the load corresponding to the first overload, and then dispatch the mobile substation to connect to the faulty node line, switch to the mobile substation to supply power and restore the power supply of the cut-off load. Once the location of the faulty node is determined, and the load at the faulty node is identified as a Class II critical load, further determination is made based on the determined fault type and the corresponding average maintenance time: If it is a short-term fault, obtain the first load amount of the line connected to the fault node, and use a heuristic algorithm to traverse the third unload amount of the lines of the two types of important load nodes around the fault node. If it is a long-term fault, first disconnect the load connected to the faulty node, and dispatch a mobile substation to connect to the faulty node line as soon as possible, switch to the mobile substation to provide power and restore the power supply to the disconnected load. To obtain the location of the fault node, when the load at the fault node is determined to be a Class III load, obtain the second load quantity of the line connected to the fault node, and use a heuristic algorithm to traverse the fifth unload quantity of the lines of the Class III load nodes around the fault node.

2. A distribution network load dispatching method as described in claim 1, characterized in that, In step S4, the load scheduling method at the faulty node is determined based on the load level, fault type, and average repair time of the fault. Specifically, this also includes: A heuristic algorithm is used to traverse the first empty load of the lines of the two types of important load nodes around the fault node. If there is a line whose first empty load is greater than or equal to the first overload, the load corresponding to the first overload is switched to the line with the first empty load, and the scheduling operation is stopped. If there is no line whose first empty load is greater than or equal to the first overload, the first empty load of the lines of the two types of important load nodes around the fault node is sorted according to the traversal results. When the sum of all the first empty loads in the sort is greater than or equal to the first overload, the load corresponding to the first overload is split and switched to each line with the corresponding first empty load according to the first empty load sort, and the scheduling operation is stopped.

3. A distribution network load dispatching method as described in claim 2, characterized in that, Step S4 further includes: If the sum of all first empty loads in the surrounding Class II important load node lines is less than the first overload, the surrounding Class II important load node line with the highest first empty load is used as the center. A heuristic algorithm is used to traverse the second empty loads of the surrounding Class III load node lines, and the difference between the first overload and the highest-ranked first empty load is calculated as the second overload. If there is a single line whose second empty load is greater than or equal to the second overload, the load corresponding to the first overload is first switched to the line with the highest-ranked first empty load, and then the load corresponding to the second overload is switched to the line with the second empty load, and the scheduling operation is terminated. If there is no single line whose second empty load is greater than or equal to the second overload, the ranking of the second empty loads of the surrounding Class III load node lines is obtained according to the traversal results. When the sum of the second empty loads is greater than or equal to the second overload, the load corresponding to the first overload is first switched to the line with the highest-ranked first empty load, and then the load corresponding to the second overload is split and switched to each line with the corresponding second empty load according to the second empty load ranking, and the scheduling operation is terminated. If the sum of all second-order unloaded loads in the three types of load nodes in the surrounding area is less than the second-order overload, then the difference between the second-order overload and the highest-ranked second-order unload is calculated as the third-order overload. Based on the second-order unload, the load corresponding to the first-order overload is first switched to the line with the highest-ranked first-order unload, then the load corresponding to the second-order overload is switched to the line with the highest-ranked second-order unload, and the load corresponding to the third-order overload is cut off in the line with the highest-ranked second-order unload, and the scheduling operation is terminated.

4. A distribution network load dispatching method as described in claim 1, characterized in that, In step S4, the load scheduling method at the faulty node is determined based on the load level, fault type, and average repair time of the fault. Specifically, this also includes: A heuristic algorithm is used to traverse the third empty load of the lines of the two types of important load nodes around the faulty node. If there is a line whose third empty load is greater than or equal to the first load, the load attached to the line of the faulty node is switched to the line with the third empty load, and the scheduling operation is stopped. If there is no line whose third empty load is greater than or equal to the first load, the third empty load of the lines of the two types of important load nodes around the faulty node is sorted according to the traversal results. When the sum of all the third empty loads in the sort is greater than or equal to the first load, the attached load is split and switched to each line with the corresponding third empty load according to the sort of third empty load, and the scheduling operation is stopped.

5. A distribution network load dispatching method as described in claim 4, characterized in that, Step S4 further includes: If the sum of all third-order unloaded quantities in the surrounding Class II important load node lines is less than the first-order unloaded quantity, take the surrounding Class II important load node line with the highest third-order unloaded quantity as the center, use a heuristic algorithm to traverse the surrounding Class III load node lines with the fourth-order unloaded quantity, and calculate the difference between the first-order unloaded quantity and the highest-order third-order unloaded quantity as the fourth overload quantity. If there exists a line whose fourth empty load is greater than or equal to the fourth overload, the first load on the faulty node line is first switched to the line with the highest third empty load, and then the load corresponding to the fourth overload is switched to the line with the fourth empty load, and the scheduling operation is terminated. If there is no line whose fourth empty load is greater than or equal to the fourth overload, the fourth empty load of the surrounding three types of load nodes is sorted according to the traversal results. When the sum of all fourth empty loads in the sort is greater than or equal to the fourth overload, the first load on the faulty node line is first switched to the line with the highest third empty load, and then the load corresponding to the fourth overload is split and switched to each line with the corresponding fourth empty load according to the fourth empty load sort, and the scheduling operation is terminated. If the sum of all fourth unloaded quantities in the three types of load nodes in the surrounding area is less than the fourth overload, then the difference between the fourth overload and the fourth unload with the highest ranking is calculated as the fifth overload. According to the ranking of the fourth unload, the first load of the faulty node line is first switched to the line with the third unload with the highest ranking. Then the load corresponding to the fourth overload is switched to the line with the fourth unload with the highest ranking. The load corresponding to the fourth overload is then cut off in the line with the fourth unload with the highest ranking. The dispatching operation is then terminated.

6. A distribution network load dispatching method as described in claim 1, characterized in that, In step S4, the load scheduling method at the faulty node is determined based on the load level, fault type, and average repair time of the fault. Specifically, this includes: A heuristic algorithm is used to traverse the fifth unloaded quantity of the three types of load nodes around the fault node. If there is a single line whose fifth unloaded quantity is greater than or equal to the second load quantity, the load attached to the fault node line is switched to the line with the fifth unloaded quantity, and the scheduling operation is terminated. If there is no single line whose fifth unloaded quantity is greater than or equal to the second load quantity, then based on the traversal results, obtain the ranking of the fifth unloaded quantities of the three types of load nodes in the surrounding area and the ranking of the load utilization rate of the faulty node line, switch the corresponding load to the line corresponding to the fifth unloaded quantity with the highest ranking, then cut off the excess load, and the scheduling operation is terminated.

7. A distribution network load dispatching method as described in claim 1, characterized in that, In step S1, establishing a fault mapping table based on the mapping relationship between fault characteristic information of historical load section data and historically determined fault types specifically includes: Extract bus and outgoing line currents, low-voltage side switch status, fuse status, and the fault type finally determined and uploaded by maintenance personnel from historical load section data. Perform Fourier transform on the bus and outgoing line currents to obtain current waveforms containing Nth harmonics. Combine the open / closed status of the low-voltage switch and the status of the line fuse at the time of the fault to establish a fault mapping table corresponding to the fault type.

8. A distribution network load dispatching system, executing the distribution network load dispatching method as described in any one of claims 1-7, characterized in that, The power distribution network load dispatching system specifically includes: sensor units, database, control center, and execution units; The sensor unit is responsible for collecting real-time operating data from each node of the power distribution network and storing it in the database; The database also stores historical operation data of the distribution network. Historical load section data when a node experiences a power failure is extracted from the historical operation data of the distribution network. A fault mapping table is established based on the mapping relationship between the fault characteristic information of the historical load section data and the historical final determined fault type. The average maintenance time of the fault type is calculated based on the historical final determined fault type. When a power failure occurs at a node, the control center reads the real-time load profile data of that node from the database, extracts the corresponding fault feature information, and looks up the fault mapping table to obtain the corresponding fault type and the average repair time of the fault. Then, based on the load level, fault type, and average repair time of the fault node, it determines the load scheduling method at the fault node and generates control commands to send to the execution unit. The execution unit includes a switching switch, which is used to receive control commands sent by the control center to perform opening and closing operations in order to regulate the load.

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