Power distribution network load dispatching system and method

Abstract

According to the power distribution network load dispatching system and method, fault feature information is extracted and a fault mapping table is established according to historical load section data in historical operation data, so that rapid positioning and identification of faults are realized, the judgment process is simplified, and the response speed when a line power supply fails is increased; when a node has a power supply fault, corresponding fault feature information is obtained according to real-time load section data at the node, a fault mapping table is searched for to obtain a corresponding fault type and fault average maintenance duration, load scheduling is carried out according to the fault type, the fault average maintenance duration and a load level, the power failure influence is marginalized, and the power failure probability is lowered. The power failure loss is reduced, and the reliability and economy of power distribution network operation are improved.

Description

Technical Field

[0001] The present invention belongs to the field of load dispatching automation of distribution network, and in particular relates to a load dispatching method and system when a node line of the distribution network fails. Background Art

[0002] In the daily operation of the distribution network, power failures often occur at nodes in the network, causing power outages on the loads mounted on the node lines. In order to improve power supply reliability 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 only executes according to the preset dispatching plan when a node failure is detected, without considering the specific type of node failure. This one-size-fits-all dispatching method cannot adapt to the increasingly complex distribution network environment. In particular, with the connection of more and more distributed power sources, there are more options for load transfer. Dispatching according to the original preset method often leads to secondary accidents due to dispatching conflicts, causing greater impacts.

[0004] In addition, usually in the process of load dispatching, the loads are not classified or the classification is relatively simple. Automatic dispatching using preset schemes can only be applied to a single scenario and cannot be applied to a large-scale 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, which discloses a method based on a preset transfer strategy to realize rapid load transfer of a single line, a single bus, and a single plant. Although this dispatching method can solve the automatic load transfer of some networks, its control accuracy and scope of application still need to be improved;

[0006] Therefore, in response to the above problems, how to develop a distribution network load dispatching system and method with wide applicability and high reliability is an issue that needs to be solved urgently. Summary of the invention

[0007] The purpose of the present invention is to overcome the shortcomings of the prior art and propose a distribution network load dispatching system and method, which can accurately define the fault type according to the fault information, and perform load dispatch according to the fault type, the average repair time of the fault and the load level, so as to marginalize the impact of power outages, reduce power outage losses, and improve the reliability and economy of distribution network operation.

[0008] The present invention provides a distribution network load dispatching method, which adopts the following steps:

[0009] S1: extract historical load section data when a node has 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 feature information of the historical load section data and the historical final determined fault type;

[0010] S2: Calculate the average maintenance time of the fault type based on the final fault type determined historically;

[0011] S3: Collect the operating data of each node in the distribution network in real time. When a power failure occurs at a node, obtain the corresponding fault feature information based on the real-time load section data at the node, and search the fault mapping table to obtain the corresponding fault type and the average repair time of the fault;

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

[0013] Preferably, in step S4, determining the scheduling mode of the load at the fault node according to the load level of the fault node, the fault type and the mean repair time of the fault specifically includes:

[0014] Get the location of the fault node. When the load at the fault node is determined to be an important load, further determine according to the determined fault type and the corresponding average maintenance time:

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

[0016] If the load rate or bus voltage of the backup power supply line is not within the preset range, the first overload of the backup power supply line is calculated, and the first no-load amounts of the second category of important load node lines around the node are traversed by a heuristic algorithm. If there is a single line whose first no-load amount is greater than or equal to the first overload amount, the load corresponding to the first overload amount is switched to the line with the first no-load amount, and the scheduling operation is terminated; if there is no single line whose first no-load amount is greater than or equal to the first overload amount, the first no-load amount ranking of the second category of important load node lines around the node is obtained according to the traversal results. When the sum of all the first no-load amounts in the ranking is greater than or equal to the first overload amount, the load corresponding to the first overload amount is split and switched to each line with the corresponding first no-load amount according to the first no-load amount ranking, and the scheduling operation is terminated.

[0017] Preferably, the step S4 further specifically includes:

[0018] If the sum of all the first no-load quantities in the surrounding second-category important load node lines is less than the first overload quantity, the surrounding second-category important load node line with the highest first no-load quantity ranking is taken as the center, and the heuristic algorithm is used to traverse the second no-load quantities of the surrounding three-category load node lines, and the difference between the first overload quantity and the first no-load quantity with the highest ranking is calculated as the second overload quantity; if there is a line whose second no-load quantity of a single line is greater than or equal to the second overload quantity, the load corresponding to the first overload quantity is first switched to the line with the highest ranking first no-load quantity, and then the load corresponding to the second overload quantity is switched to the line with the second no-load quantity, and the dispatching operation is terminated; if there is no line whose second no-load quantity of a single line is greater than or equal to the second overload quantity, then according to the traversal result, the second no-load quantity ranking of the surrounding three-category load node lines is obtained, and when the sum of the second no-load quantities is greater than or equal to the second overload quantity, the load corresponding to the first overload quantity is first switched to the line with the highest ranking first no-load quantity, and then the load corresponding to the second overload quantity is split and switched to each line with the corresponding second no-load quantity according to the second no-load quantity ranking, and the dispatching operation is terminated;

[0019] If the sum of all the second no-load quantities in the three types of surrounding load node lines is less than the second overload quantity, the difference between the second overload quantity and the second no-load quantity with the highest ranking is calculated as the third overload quantity. According to the ranking of the second no-load quantities, the load corresponding to the first overload quantity is first switched to the line with the first no-load quantity with the highest ranking, and then the load corresponding to the second overload quantity is switched to the line with the second no-load quantity with the highest ranking, and the load corresponding to the third overload quantity is correspondingly cut off in the line with the second no-load quantity with the highest ranking, and the scheduling operation is terminated.

[0020] Preferably, the step S4 further specifically includes:

[0021] If it is a long-term fault, first switch the node to the backup power line, and then detect the load rate and bus voltage of the backup power line. If the load rate and bus voltage of the backup power line are within the preset range, the dispatching operation is terminated; 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 in 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 access the fault node line, switch to the mobile substation for power supply and restore the power supply of the cut-off load.

[0022] Preferably, in step S4, determining the scheduling mode of the load at the fault node according to the load level of the fault node, the fault type and the mean repair time of the fault specifically includes:

[0023] Get the location of the fault node. When the load at the fault node is determined to be a Class II important load, further determine according to the determined fault type and the corresponding average maintenance time:

[0024] If it is a short-term fault, obtain the first load quantity mounted on the node line, and use the heuristic algorithm to traverse the third empty load quantity of the second category important load node lines around the node. If there is a single line whose third empty load quantity is greater than or equal to the first load quantity, the load mounted on the node line is switched to the line with the third empty load quantity, and the scheduling operation is terminated; if there is no single line whose third empty load quantity is greater than or equal to the first load quantity, then according to the traversal result, obtain the third empty load quantity ranking of the second category important load node lines around the node. When the sum of all the third empty load quantities in the ranking is greater than or equal to the first load quantity, the mounted load is split and switched to each line with the corresponding third empty load quantity according to the third empty load quantity ranking, and the scheduling operation is terminated.

[0025] Preferably, the step S4 further specifically includes:

[0026] If the sum of all the third empty loads in the surrounding second-category important load node lines is less than the first load, the surrounding second-category important load node line with the highest third empty load is taken as the center, and the heuristic algorithm is used to traverse the fourth empty loads of the surrounding three-category load node lines, and the difference between the first load and the third empty load with the highest ranking is calculated as the fourth overload;

[0027] If there is a line whose fourth no-load amount is greater than or equal to the fourth overload amount, the first load amount mounted on the node line is first switched to the line with the third no-load amount with the highest ranking, and then the load corresponding to the fourth overload amount is switched to the line with the fourth no-load amount, and the scheduling operation is terminated; if there is no line whose fourth no-load amount is greater than or equal to the fourth overload amount, then according to the traversal result, the fourth no-load amount ranking of the surrounding three types of load node lines is obtained, and when the sum of all fourth no-load amounts in the ranking is greater than or equal to the fourth overload amount, the first load amount mounted on the node line is first switched to the line with the third no-load amount with the highest ranking, and then the load corresponding to the fourth overload amount is split and switched to each line with the corresponding fourth no-load amount according to the fourth no-load amount ranking, and the scheduling operation is terminated;

[0028] If the sum of all fourth no-load quantities in the surrounding three types of load node lines is less than the fourth overload quantity, the difference between the fourth overload quantity and the fourth no-load quantity with the highest ranking is calculated as the fifth overload quantity. According to the ranking of the fourth no-load quantity, the first load quantity mounted on the node line is first switched to the line with the third no-load quantity with the highest ranking, and then the load corresponding to the fourth overload quantity is switched to the line with the fourth no-load quantity with the highest ranking, and the load corresponding to the fourth overload quantity is correspondingly cut off in the line with the fourth no-load quantity with the highest ranking, and the scheduling operation is terminated.

[0029] Preferably, the step S4 further specifically includes:

[0030] If it is a long-term fault, the load mounted on the node will be cut off first, and the mobile substation will be dispatched to access the faulty node line as soon as possible, and the power supply will be switched to the mobile substation and the power supply of the cut load will be restored.

[0031] Preferably, in step S4, determining the scheduling mode of the load at the fault node according to the load level of the fault node, the fault type and the mean 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 amount mounted on the node line, and use a heuristic algorithm to traverse the fifth empty load amount of the Class III load node lines around the node. If there is a single line whose fifth empty load amount is greater than or equal to the second load amount, then switch the load mounted on the node line to the line with the fifth empty load amount, and terminate the dispatching operation.

[0033] If there is no single line whose fifth idle volume is greater than or equal to the second load volume, then based on the traversal results, the fifth idle volume ranking of the three types of load node lines in the surrounding area and the load utilization ranking of the faulty node line are obtained, and the corresponding load is switched to the line corresponding to the fifth idle volume with the highest ranking, and then the excess load is cut off and the scheduling operation is terminated.

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

[0035] The busbar and outgoing line currents, low-voltage side switch status, fuse status, and the fault type finally determined and uploaded by maintenance personnel are extracted from the historical load section data, and the busbar and outgoing line currents are Fourier transformed to obtain the current waveform containing Nth harmonics. Combined with the open / closed status of the low-voltage switch and the line fuse status at the time of the fault, a fault mapping table is established corresponding to the fault type.

[0036] In order to solve the above problems, the present invention also provides a distribution network load dispatching system, the load dispatching system specifically comprises: a sensor unit, a database, a control center and an execution unit;

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

[0038] The database also stores historical operation data of the distribution network, extracts historical load section data when a node has a power failure from the historical operation data of the distribution network, establishes a fault mapping table based on the mapping relationship between the fault feature information of the historical load section data and the historically finalized fault type; and calculates the average maintenance time of the fault type based on the historically finalized fault type;

[0039] When a power failure occurs at a node, the control center reads the real-time load section data at the node from the database, extracts the corresponding fault feature information, and searches the fault mapping table to obtain the corresponding fault type and the average repair time of the fault; then, according to the load level, fault type and average repair time of the fault node, the control center determines the scheduling mode of the load at the fault node, generates a control instruction and sends it to the execution unit;

[0040] The execution unit includes a switching switch, which is used to receive a control instruction sent by a control center to perform an opening and closing operation to perform load regulation.

[0041] The beneficial effects of the present invention are as follows: 1. First, the fault type is determined by combining the current transformation waveform, switch and insurance status information in the cross-sectional data, especially the harmonic waveform developed in the Fourier transform of the current data, firstly accurately defining the fault, and establishing a fault relationship mapping table based on this, so as to facilitate the rapid positioning and identification of the fault, simplify the judgment process, and improve the response speed when the line power supply fails;

[0042] 2. When dispatching loads, the load dispatching method is determined in combination with the average repair time determined according to the fault type, which is more in line with the actual scenario, the dispatching method is more reasonable, and the applicability of the system and the utilization rate of equipment are improved;

[0043] 3. When dispatching loads, a heuristic algorithm is used to quickly obtain available transfer lines, and multiple transfers are used to give priority to restoring power supply to important loads, marginalize the impact of power outages, reduce power outage losses, and improve the reliability and economy of distribution network operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a step diagram of the load dispatching method of distribution network;

[0045] Figure 2 This is the control schematic diagram of the distribution network load dispatching system. DETAILED DESCRIPTION

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

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

[0048] S1: extract historical load section data when a node has 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 feature information of the historical load section data and the historical final determined fault type;

[0049] S2: Calculate the average maintenance time of the fault type based on the final fault type determined historically;

[0050] S3: Collect the operating data of each node in the distribution network in real time. When a power failure occurs at a node, obtain the corresponding fault feature information based on the real-time load section data at the node, and search the fault mapping table to obtain the corresponding fault type and the average repair time of the fault;

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

[0052] Preferably, in step S4, determining the scheduling mode of the load at the fault node according to the load level of the fault node, the fault type and the mean repair time of the fault specifically includes:

[0053] Get the location of the fault node. When the load at the fault node is determined to be an important load, further determine according to the determined fault type and the corresponding average maintenance time:

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

[0055] If the load rate or bus voltage of the backup power supply line is not within the preset range, the first overload of the backup power supply line is calculated, and the first no-load amounts of the second category of important load node lines around the node are traversed by a heuristic algorithm. If there is a single line whose first no-load amount is greater than or equal to the first overload amount, the load corresponding to the first overload amount is switched to the line with the first no-load amount, and the scheduling operation is terminated; if there is no single line whose first no-load amount is greater than or equal to the first overload amount, the first no-load amount ranking of the second category of important load node lines around the node is obtained according to the traversal results. When the sum of all the first no-load amounts in the ranking is greater than or equal to the first overload amount, the load corresponding to the first overload amount is split and switched to each line with the corresponding first no-load amount according to the first no-load amount ranking, and the scheduling operation is terminated.

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

[0057] Preferably, the step S4 further specifically includes:

[0058] If the sum of all the first no-load quantities in the surrounding second-category important load node lines is less than the first overload quantity, the surrounding second-category important load node line with the highest first no-load quantity ranking is taken as the center, and the heuristic algorithm is used to traverse the second no-load quantities of the surrounding three-category load node lines, and the difference between the first overload quantity and the first no-load quantity with the highest ranking is calculated as the second overload quantity; if there is a line whose second no-load quantity of a single line is greater than or equal to the second overload quantity, the load corresponding to the first overload quantity is first switched to the line with the highest ranking first no-load quantity, and then the load corresponding to the second overload quantity is switched to the line with the second no-load quantity, and the dispatching operation is terminated; if there is no line whose second no-load quantity of a single line is greater than or equal to the second overload quantity, then according to the traversal result, the second no-load quantity ranking of the surrounding three-category load node lines is obtained, and when the sum of the second no-load quantities is greater than or equal to the second overload quantity, the load corresponding to the first overload quantity is first switched to the line with the highest ranking first no-load quantity, and then the load corresponding to the second overload quantity is split and switched to each line with the corresponding second no-load quantity according to the second no-load quantity ranking, and the dispatching operation is terminated;

[0059] If the sum of all the second no-load quantities in the three types of surrounding load node lines is less than the second overload quantity, the difference between the second overload quantity and the second no-load quantity with the highest ranking is calculated as the third overload quantity. According to the ranking of the second no-load quantities, the load corresponding to the first overload quantity is first switched to the line with the first no-load quantity with the highest ranking, and then the load corresponding to the second overload quantity is switched to the line with the second no-load quantity with the highest ranking, and the load corresponding to the third overload quantity is correspondingly cut off in the line with the second no-load quantity with the highest ranking, and the scheduling operation is terminated.

[0060] Specifically, in the line having the second unloaded amount with the highest ranking, correspondingly removing the load corresponding to the third overload amount may include:

[0061] According to the historical operation data of the distribution network, the daily average operation time of the load mounted in the line with the second highest no-load capacity is counted, and the daily average operation time is sorted, and the load is removed in order from low to high until the sum of the removed loads is greater than or equal to the load corresponding to the third overload capacity:

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

[0063] Preferably, the step S4 further specifically includes:

[0064] If it is a long-term fault, first switch the node to the backup power line, and then detect the load rate and bus voltage of the backup power line. If the load rate and bus voltage of the backup power line are within the preset range, the dispatching operation is terminated; 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 in 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 access the fault node line, switch to the mobile substation for power supply and restore the power supply of the cut-off load.

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

[0066] The obtaining of the load utilization ranking in the backup power supply line and removing the load corresponding to the first overload amount according to the load utilization ranking may include:

[0067] The historical annual utilization rate of the load mounted on the backup power supply line is calculated based on the historical operation data of the distribution network, and the historical annual utilization rate ranking is obtained. The load is then removed in order from low to high until the sum of the removed loads is greater than or equal to the load corresponding to the first overload.

[0068] Among them, R η is the historical annual utilization rate of the load, t is the total operating time of the load throughout the year, and T is the length of a year;

[0069] Preferably, in step S4, determining the scheduling mode of the load at the fault node according to the load level of the fault node, the fault type and the mean repair time of the fault specifically includes:

[0070] Get the location of the fault node. When the load at the fault node is determined to be a Class II important load, further determine according to the determined fault type and the corresponding average maintenance time:

[0071] If it is a short-term fault, obtain the first load quantity mounted on the node line, and use the heuristic algorithm to traverse the third empty load quantity of the second category important load node lines around the node. If there is a single line whose third empty load quantity is greater than or equal to the first load quantity, the load mounted on the node line is switched to the line with the third empty load quantity, and the scheduling operation is terminated; if there is no single line whose third empty load quantity is greater than or equal to the first load quantity, then according to the traversal result, obtain the third empty load quantity ranking of the second category important load node lines around the node. When the sum of all the third empty load quantities in the ranking is greater than or equal to the first load quantity, the mounted load is split and switched to each line with the corresponding third empty load quantity according to the third empty load quantity ranking, and the scheduling operation is terminated.

[0072] Preferably, the step S4 further specifically includes:

[0073] If the sum of all the third empty loads in the surrounding second-category important load node lines is less than the first load, the surrounding second-category important load node line with the highest third empty load is taken as the center, and the heuristic algorithm is used to traverse the fourth empty loads of the surrounding three-category load node lines, and the difference between the first load and the third empty load with the highest ranking is calculated as the fourth overload;

[0074] If there is a line whose fourth empty load is greater than or equal to the fourth overload, the first load on the node line is first switched to the line with the third empty load with the highest ranking, and then the load corresponding to the fourth overload is switched to the line with the fourth empty load, and the dispatching operation is terminated;

[0075] If there is no single line whose fourth empty load is greater than or equal to the fourth overload, then according to the traversal result, the fourth empty load ranking of the three types of load node lines in the surrounding area is obtained. When the sum of all the fourth empty loads in the ranking is greater than or equal to the fourth overload, the first load mounted on 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 split and switched to each line with the corresponding fourth empty load according to the fourth empty load ranking, and the dispatching operation is terminated;

[0076] If the sum of all fourth no-load quantities in the surrounding three types of load node lines is less than the fourth overload quantity, the difference between the fourth overload quantity and the fourth no-load quantity with the highest ranking is calculated as the fifth overload quantity. According to the ranking of the fourth no-load quantity, the first load quantity mounted on the node line is first switched to the line with the third no-load quantity with the highest ranking, and then the load corresponding to the fourth overload quantity is switched to the line with the fourth no-load quantity with the highest ranking, and the load corresponding to the fourth overload quantity is correspondingly cut off in the line with the fourth no-load quantity with the highest ranking, and the scheduling operation is terminated.

[0077] Preferably, the step S4 further specifically includes:

[0078] If it is a long-term fault, the load mounted on the node will be cut off first, and the mobile substation will be dispatched to access the faulty node line as soon as possible, and the power supply will be switched to the mobile substation and the power supply of the cut load will be restored.

[0079] Preferably, if it is confirmed to be a long-term fault, the dispatching duration of the mobile substation is also confirmed. If the dispatching duration of the mobile substation is less than or equal to the first preset duration, the load mounted on the node is first cut off, and the mobile substation is dispatched to access the fault node line as soon as possible, and the power supply is switched to the mobile substation and the power supply of the cut load is restored;

[0080] If it is confirmed that the dispatching time of the mobile substation is greater than the first preset time, the first load amount mounted on the node line is obtained, and the third empty load amount of the second-class important load node lines around the node is traversed by a heuristic algorithm. If there is a single line whose third empty load amount is greater than or equal to the first load amount, the load mounted on the node line is switched to the line with the third empty load amount, 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 according to the traversal result, the third empty load ranking of the surrounding second-class important load node lines and the load utilization ranking of the fault node line are obtained, and the corresponding load is switched to the line corresponding to the third empty load with the highest ranking, and the dispatching operation is terminated;

[0082] Specifically, switching the corresponding load to the line corresponding to the third highest ranked no-load amount may include: cutting off the load in order of load utilization from low to high until the sum of the cut load amounts is greater than or equal to the load amount corresponding to the third highest ranked no-load amount.

[0083] Preferably, in step S4, determining the scheduling mode of the load at the fault node according to the load level of the fault node, the fault type and the mean 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 amount mounted on the node line, and use a heuristic algorithm to traverse the fifth empty load amount of the Class III load node lines around the node. If there is a single line whose fifth empty load amount is greater than or equal to the second load amount, then switch the load mounted on the node line to the line with the fifth empty load amount, and terminate the dispatching operation.

[0085] If there is no single line whose fifth empty load is greater than or equal to the second load, then according to the traversal result, the fifth empty load ranking of the three types of load node lines around and the load utilization ranking of the fault node line are obtained, and the corresponding load is switched to the line corresponding to the fifth empty load with the highest ranking, and then the redundant load is cut off, and the dispatching operation is terminated;

[0086] Specifically, switching the corresponding load to the line corresponding to the fifth highest ranked no-load amount may include: cutting off the load in order of load utilization from low to high until the sum of the cut load amounts is greater than or equal to the load amount corresponding to the fifth highest ranked no-load amount.

[0087] Preferably, for the load scheduling operation performed when a power failure occurs in a node, the load scheduling operation is restored according to the operation sequence after the failure is restored for a second preset time, and the load power supply is restored.

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

[0089] The busbar and outgoing line currents, low-voltage side switch status, fuse status, and the fault type finally determined and uploaded by maintenance personnel are extracted from the historical load section data, and the busbar and outgoing line currents are Fourier transformed to obtain the current waveform containing Nth harmonics. Combined with the open / closed status of the low-voltage switch and the line fuse status at the time of the fault, a fault mapping table is established corresponding to the fault type.

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

[0091] In order to solve the above problems, the present invention also provides a 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 the operating data of each node in the distribution network in real time and storing it in the database;

[0093] The database also stores historical operation data of the distribution network, extracts historical load section data when a node has a power failure from the historical operation data of the distribution network, establishes a fault mapping table based on the mapping relationship between the fault feature information of the historical load section data and the historically finalized fault type; and calculates the average maintenance time of the fault type based on the historically finalized fault type;

[0094] When a power failure occurs at a node, the control center reads the real-time load section data at the node from the database, extracts the corresponding fault feature information, and searches the fault mapping table to obtain the corresponding fault type and the average repair time of the fault; then, according to the load level, fault type and average repair time of the fault node, the control center determines the scheduling mode of the load at the fault node, generates a control instruction and sends it to the execution unit;

[0095] The execution unit includes a switching switch, which is used to receive a control instruction sent by a control center to perform an opening and closing operation to perform load regulation.

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

[0097] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A distribution network load dispatching method, characterized in that: Use the following steps: S1: extract historical load section data when a node has 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 feature information of the historical load section data and the historical final determined fault type; S2: Calculate the average maintenance time of the fault type based on the final fault type determined historically; S3: Collect the operating data of each node in the distribution network in real time. When a power failure occurs at a node, obtain the corresponding fault feature information based on the real-time load section data at the node, and search the fault mapping table to obtain the corresponding fault type and the average repair time of the fault; S4: Determine the scheduling method of the load at the fault node according to the load level of the fault node, the fault type and the average repair time of the fault.

2. A method for load dispatching of a distribution network as claimed in claim 1, characterized in that: In step S4, according to the load level of the fault node, the fault type and the average repair time of the fault, the scheduling method of the load at the fault node is determined, which specifically includes: Get the location of the fault node. When the load at the fault node is determined to be an important load, further determine according to the determined fault type and the corresponding average maintenance time: If it is a short-term fault, the node will be switched to the backup power line first, and then the load rate and bus voltage of the backup power line will be detected. If the load rate and bus voltage of the backup power line are within the preset range, the dispatching operation will be terminated; If the load rate or bus voltage of the backup power supply line is not within the preset range, the first overload of the backup power supply line is calculated, and the first no-load amounts of the second category of important load node lines around the node are traversed by a heuristic algorithm. If there is a single line whose first no-load amount is greater than or equal to the first overload amount, the load corresponding to the first overload amount is switched to the line with the first no-load amount, and the scheduling operation is terminated; if there is no single line whose first no-load amount is greater than or equal to the first overload amount, the first no-load amount ranking of the second category of important load node lines around the node is obtained according to the traversal results. When the sum of all the first no-load amounts in the ranking is greater than or equal to the first overload amount, the load corresponding to the first overload amount is split and switched to each line with the corresponding first no-load amount according to the first no-load amount ranking, and the scheduling operation is terminated.

3. A distribution network load dispatching method as claimed in claim 2, characterized in that: The step S4 further specifically includes: If the sum of all the first no-load quantities in the surrounding second-category important load node lines is less than the first overload quantity, the surrounding second-category important load node line with the highest first no-load quantity ranking is taken as the center, and the heuristic algorithm is used to traverse the second no-load quantities of the surrounding three-category load node lines, and the difference between the first overload quantity and the first no-load quantity with the highest ranking is calculated as the second overload quantity; if there is a line whose second no-load quantity of a single line is greater than or equal to the second overload quantity, the load corresponding to the first overload quantity is first switched to the line with the highest ranking first no-load quantity, and then the load corresponding to the second overload quantity is switched to the line with the second no-load quantity, and the dispatching operation is terminated; if there is no line whose second no-load quantity of a single line is greater than or equal to the second overload quantity, then according to the traversal result, the second no-load quantity ranking of the surrounding three-category load node lines is obtained, and when the sum of the second no-load quantities is greater than or equal to the second overload quantity, the load corresponding to the first overload quantity is first switched to the line with the highest ranking first no-load quantity, and then the load corresponding to the second overload quantity is split and switched to each line with the corresponding second no-load quantity according to the second no-load quantity ranking, and the dispatching operation is terminated; If the sum of all the second no-load quantities in the three types of surrounding load node lines is less than the second overload quantity, the difference between the second overload quantity and the second no-load quantity with the highest ranking is calculated as the third overload quantity. According to the ranking of the second no-load quantities, the load corresponding to the first overload quantity is first switched to the line with the first no-load quantity with the highest ranking, and then the load corresponding to the second overload quantity is switched to the line with the second no-load quantity with the highest ranking, and the load corresponding to the third overload quantity is correspondingly cut off in the line with the second no-load quantity with the highest ranking, and the scheduling operation is terminated.

4. A method for load dispatching of a distribution network as claimed in claim 3, characterized in that , the step S4 further specifically includes: If it is a long-term fault, first switch the node to the backup power line, and then detect the load rate and bus voltage of the backup power line. If the load rate and bus voltage of the backup power line are within the preset range, the dispatching operation is terminated; 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 in 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 access the fault node line, switch to the mobile substation for power supply and restore the power supply of the cut-off load.

5. A method for load dispatching of a distribution network as claimed in claim 1, characterized in that In step S4, according to the load level, fault type and average repair time of the fault node, the scheduling method of the load at the fault node is determined, which specifically includes: Get the location of the fault node. When the load at the fault node is determined to be a Class II important load, further determine according to the determined fault type and the corresponding average maintenance time: If it is a short-term fault, obtain the first load quantity mounted on the node line, and use the heuristic algorithm to traverse the third empty load quantity of the second category important load node lines around the node. If there is a single line whose third empty load quantity is greater than or equal to the first load quantity, the load mounted on the node line is switched to the line with the third empty load quantity, and the scheduling operation is terminated; if there is no single line whose third empty load quantity is greater than or equal to the first load quantity, then according to the traversal result, obtain the third empty load quantity ranking of the second category important load node lines around the node. When the sum of all the third empty load quantities in the ranking is greater than or equal to the first load quantity, the mounted load is split and switched to each line with the corresponding third empty load quantity according to the third empty load quantity ranking, and the scheduling operation is terminated.

6. A method for load dispatching of a distribution network as claimed in claim 5, characterized in that , the step S4 further specifically includes: If the sum of all the third empty loads in the surrounding second-category important load node lines is less than the first load, the surrounding second-category important load node line with the highest third empty load is taken as the center, and the heuristic algorithm is used to traverse the fourth empty loads of the surrounding three-category load node lines, and the difference between the first load and the third empty load with the highest ranking is calculated as the fourth overload; If there is a line whose fourth no-load amount is greater than or equal to the fourth overload amount, the first load amount mounted on the node line is first switched to the line with the third no-load amount with the highest ranking, and then the load corresponding to the fourth overload amount is switched to the line with the fourth no-load amount, and the scheduling operation is terminated; if there is no line whose fourth no-load amount is greater than or equal to the fourth overload amount, then according to the traversal result, the fourth no-load amount ranking of the surrounding three types of load node lines is obtained, and when the sum of all fourth no-load amounts in the ranking is greater than or equal to the fourth overload amount, the first load amount mounted on the node line is first switched to the line with the third no-load amount with the highest ranking, and then the load corresponding to the fourth overload amount is split and switched to each line with the corresponding fourth no-load amount according to the fourth no-load amount ranking, and the scheduling operation is terminated; If the sum of all fourth no-load quantities in the surrounding three types of load node lines is less than the fourth overload quantity, the difference between the fourth overload quantity and the fourth no-load quantity with the highest ranking is calculated as the fifth overload quantity. According to the ranking of the fourth no-load quantity, the first load quantity mounted on the node line is first switched to the line with the third no-load quantity with the highest ranking, and then the load corresponding to the fourth overload quantity is switched to the line with the fourth no-load quantity with the highest ranking, and the load corresponding to the fourth overload quantity is correspondingly cut off in the line with the fourth no-load quantity with the highest ranking, and the scheduling operation is terminated.

7. A method for load dispatching of a distribution network as claimed in claim 6, characterized in that , the step S4 further specifically includes: If it is a long-term fault, the load mounted on the node will be cut off first, and the mobile substation will be dispatched to access the faulty node line as soon as possible, and the power supply will be switched to the mobile substation and the power supply of the cut load will be restored.

8. A method for load dispatching of a distribution network as claimed in claim 1, characterized in that In step S4, according to the load level, fault type and average repair time of the fault node, the scheduling method of the load at the fault node is determined, which specifically includes: 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 amount mounted on the node line, and use a heuristic algorithm to traverse the fifth empty load amount of the Class III load node lines around the node. If there is a single line whose fifth empty load amount is greater than or equal to the second load amount, then switch the load mounted on the node line to the line with the fifth empty load amount, and terminate the dispatching operation. If there is no single line whose fifth idle volume is greater than or equal to the second load volume, then based on the traversal results, the fifth idle volume ranking of the three types of load node lines in the surrounding area and the load utilization ranking of the faulty node line are obtained, and the corresponding load is switched to the line corresponding to the fifth idle volume with the highest ranking, and then the excess load is cut off and the scheduling operation is terminated.

9. A method for load dispatching of a distribution network as claimed in claim 1, characterized in that In step S1, the 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 fault type, which specifically includes: The busbar and outgoing line currents, low-voltage side switch status, fuse status, and the fault type finally determined and uploaded by maintenance personnel are extracted from the historical load section data, and the busbar and outgoing line currents are Fourier transformed to obtain the current waveform containing Nth harmonics. Combined with the open / closed status of the low-voltage switch and the line fuse status at the time of the fault, a fault mapping table is established corresponding to the fault type.

10. A distribution network load dispatching system, executing the distribution network load dispatching method according to any one of claims 1 to 9, characterized in that ,The load dispatching system of the distribution network specifically includes: sensor unit, database, control center and ,execution unit; The sensor unit is responsible for collecting the operating data of each node in the distribution network in real time and storing it in the database; The database also stores historical operation data of the distribution network, extracts historical load section data when a node has a power failure from the historical operation data of the distribution network, establishes a fault mapping table based on the mapping relationship between the fault feature information of the historical load section data and the historically finalized fault type; and calculates the average maintenance time of the fault type based on the historically finalized fault type; When a power failure occurs at a node, the control center reads the real-time load section data at the node from the database, extracts the corresponding fault feature information, and searches the fault mapping table to obtain the corresponding fault type and the average repair time of the fault; then, according to the load level, fault type and average repair time of the fault node, the control center determines the scheduling mode of the load at the fault node, generates a control instruction and sends it to the execution unit; The execution unit includes a switching switch, which is used to receive a control instruction sent by a control center to perform an opening and closing operation to perform load regulation.

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