Power distribution network load transfer method and device

Abstract

The application provides a power distribution network load transfer method and device, the method comprises the following steps: obtaining a power distribution network fault signal, the fault signal comprises a bus voltage, a main transformer low-voltage side switch, each outgoing line current and a main transformer protection signal; after the fault signal meets a preset condition, collecting load section data of a line and a transferred line, excluding the case that the line cannot be used as a line, obtaining a plurality of transfer schemes with priority; based on a preset load transfer mode, performing load transfer according to the transfer scheme. Real-time acquisition of the fault signal of the power distribution network, after meeting the preset condition, based on the preset transfer strategy, load transfer is carried out, which can be applied to daily operation overload, overrun, maintenance, change of operation mode and the like, realizes fast load transfer of a single line, a single bus and a single station, and can also be applied to the fast recovery of power supply of a 10-kilovolt bus which cannot be recovered by the main network under large-area power cut of the distribution network, and ensures the power supply reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power grid load transfer, and in particular to a power distribution network load transfer method and device. BACKGROUND

[0002] As a facility for transforming voltage, exchanging power and collecting and distributing electric energy, a substation is a key connection point of a power grid network. In order to better improve the power supply guarantee capability of a substation for lower-level lines, the substation is usually powered by double incoming lines, two or more main transformers are operated, and a backup automatic switching device is configured to quickly restore power supply in a non-fault area.

[0003] When the substation itself is in a single-line, single-main-transformer or single-channel condition due to reasons such as connection mode, planned maintenance, unplanned maintenance, and faults, the traditional backup automatic switching device cannot be applied. Once the incoming line or the main transformer fails to trip, the medium and low voltage buses will lose power, causing multiple power supply lines in the power distribution network to stop working and large-area loads to lose power supply.

[0004] The existing power distribution automation master station system feeder automation function can only automatically restore power supply in a non-fault area when a single power distribution line fails, and cannot start the self-healing function and automatically restore power supply when the 10 kilovolt (kV) bus loses voltage due to a failure of the upper-level power supply. At present, after the 10 kV bus loses power, the dispatcher manually queries information such as whether there is a tie switch, whether the tie switch is a tie switch of a different station, the daily maximum load of the line, the maximum allowable current of the line, the load of the main transformer, and the like, which is time-consuming and requires high experience and ability of the dispatcher, and the time for restoring power supply to users is long, which cannot meet the requirements of users for power supply reliability.

[0005] Before daily operation overload, overrun, maintenance, and change of operation mode, load transfer or load reversal in cooperation with the upper-level work is required, the maximum allowable current, line cable and other factors are checked by the head of the planning group of the dispatching management department, the dispatcher manually prepares a load transfer scheme, and after verification by the dispatcher, the load transfer is operated step by step, the closing and opening currents and the switch positions are confirmed, which is time-consuming and laborious and prone to errors. SUMMARY

[0006] The present application provides a power distribution network load transfer method and device, which is used to solve the problem that the existing power distribution network takes a long time to restore power supply after a fault and cannot meet the requirements of users for power supply reliability.

[0007] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0008] The present application provides a power distribution network load transfer method, which comprises the following steps:

[0009] Obtaining a power distribution network fault signal, the fault signal including bus voltage, main transformer low-voltage side switch, each outgoing line current and main transformer protection signal;

[0010] After the fault signal meets a preset condition, collecting load section data of the line and the transferred supply line, excluding a case that cannot be used as a line, and obtaining a plurality of transferred supply schemes with priority;

[0011] Based on a preset load transferred supply mode, performing load transferred supply according to the transferred supply scheme.

[0012] Further, the preset condition includes a start condition and a lock condition, and the start condition and the lock condition are sequentially judged.

[0013] Further, the start condition is specifically:

[0014] All power supply of the transformer substation bus, power supply of the transformer substation outgoing line topology and no current of the main transformer low-voltage side switch.

[0015] Further, the lock condition is specifically:

[0016] There is an outgoing line protection action signal, but the switch is not tripped;

[0017] There is a backup protection action signal;

[0018] All station channels are exited;

[0019] The main transformer low-voltage side switch is remotely controlled to open;

[0020] Any one of the above conditions triggers the lock.

[0021] Further, the case that cannot be used as a line includes:

[0022] The transferred supply operation switch or the transferred supply path is not allowed to be used as a line;

[0023] The quality code of the contact switch is double-bit error;

[0024] Single-phase ground fault occurs in the line or the feeder automation fault is not processed and ended;

[0025] The switch position on the transferred supply path is in the split position or has no voltage;

[0026] Any one of the above conditions cannot be used as a line.

[0027] Further, the process of performing load transferred supply is specifically:

[0028] Disconnecting each side switch of the main transformer, isolating the main transformer;

[0029] Disconnecting all outgoing line switches of the bus.

[0030] The outgoing line of the inter-station communication is recovered by the communication switch, and power is supplied to the outgoing line switch;

[0031] According to the priority order, the outgoing line switches of the non-inter-station communication lines are closed one by one to restore power supply, and the power transfer is stopped when the maximum power supply capacity is reached or all loads are transferred.

[0032] Further, the method further comprises performing a transfer mode verification and a safety verification on the transfer scheme.

[0033] Further, the transfer mode verification specifically comprises:

[0034] Power source point tracking is performed on the transfer line and the carrier line to determine whether there is a loop closing phase angle difference between the two lines, and based on the determination result, a loop closing power adjustment mode or a power-off power adjustment mode is selected;

[0035] For lines that are not allowed to loop across regions, the 220V bus of the transfer line and the carrier line is traced back, and based on the partition maintained by the 220V bus, it is determined whether the transfer line and the carrier line are in the same power grid partition, if yes, the loop closing power adjustment mode is adopted, and if no, the power-off power adjustment mode is adopted.

[0036] The second aspect of the present application provides a power distribution network load transfer device which can be deployed in a power distribution automation system, the device further comprises:

[0037] A signal acquisition module is configured to acquire a power distribution network fault signal, the fault signal comprising bus voltage, main transformer low voltage side switch, each outgoing line current and main transformer protection signal;

[0038] A transfer processing module is configured to collect load section data of the carrier line and the transferred line after the fault signal meets a preset condition, exclude cases that cannot be used as a carrier line, and obtain a plurality of transfer schemes with priority;

[0039] A transfer execution module is configured to perform load transfer according to the transfer scheme based on a preset load transfer mode.

[0040] Further, the device further comprises a verification module, and the verification module is configured to perform a transfer mode verification and a safety verification on the transfer scheme.

[0041] The power distribution network load transfer device of the second aspect of the present application can realize the method of the first aspect and each implementation manner of the first aspect, and achieve the same effect.

[0042] The effects provided in the summary are only the effects of the embodiments, not all the effects of the invention, and one of the above technical solutions has the following advantages or beneficial effects:

[0043] 1. The present invention obtains fault signals of the distribution network in real time, determines whether preset conditions are met, and performs load transfer based on a preset transfer strategy after the preset conditions are met. It can be applied to daily operation overload, over-limit, maintenance, change of operation mode and other tasks to achieve rapid load transfer of a single line, a single bus, and a single plant station. It can also be applied to large-scale power outages in the distribution network to quickly restore power to the 10kV bus that cannot be restored by the main network, thereby ensuring power supply reliability.

[0044] 2. Before starting the load transfer action, the starting conditions and locking conditions are judged separately, and the situations that are not allowed to be used as the lead line are excluded, which ensures the accuracy of the load transfer, avoids erroneous operations, and further ensures the reliability of power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0046] Figure 1 is a schematic flow chart of an embodiment of the method of the present invention;

[0047] Figure 2 It is a flowchart of a specific implementation method of the method embodiment of the present invention;

[0048] Figure 3 Schematic diagram of the preset conditions for starting the power transfer in the embodiment of the method of the present invention;

[0049] Figure 4 is a schematic diagram of a flow chart for performing load transfer in an embodiment of the method of the present invention;

[0050] Figure 5 Schematic diagram of a model for practical verification of the above method provided by the present invention;

[0051] Figure 6 is based on Figure 5 The simulation test results of the No. 1 main transformer of Junbu Station after differential protection operation to verify the model;

[0052] Figure 7 It is a structural schematic diagram of an embodiment of the device of the present invention. DETAILED DESCRIPTION

[0053] To clearly illustrate the technical features of the present application, the following detailed description is made with reference to the accompanying drawings. The disclosure below provides many different embodiments or examples for implementing the various structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described below. In addition, the present application can repeatedly refer to numerals and / or letters in different examples. Such repetition is for the purpose of simplification and clarity, and does not indicate the relationship between the various embodiments and / or settings being discussed. It should be noted that the components illustrated in the drawings are not necessarily drawn to scale. The present application omits the description of well-known components and processing techniques and processes to avoid unnecessarily limiting the present application.

[0054] The present application provides an all-round one-key transfer supply technology for smart power distribution network. The technology can be applied to daily work, real-time analysis of transferable lines, generation of operation strategy, sequential execution on operation interface, realization of single line, single bus and single station load transfer, and can also be applied to large-area power cut scenario of distribution network, analysis of 10kV bus which cannot be restored by main network, and pushing of transfer supply scheme according to system preset transfer supply strategy priority. The dispatcher can select "one-key execution", or edit the load transfer scheme, and after automatic or manual confirmation, safely transfer the affected load to the new power supply point, so as to minimize the power cut range caused by accidents or daily work.

[0055] At present, power distribution network dispatching and production field widely adopts power distribution automation system. The power distribution automation master station system is a real-time state acquisition based, abnormal perception and on-site processing oriented real-time acquisition and control system of power distribution network, which mainly realizes basic functions of power distribution network data acquisition and monitoring, operation and control, model / graph management, comprehensive alarm analysis, feeder automation, topology analysis application, accident inversion, and expansion functions of power distribution network grounding fault analysis, operation trend analysis, terminal management, power supply capacity analysis, line loss calculation support function, alarm management, and distribution network index management, and has the function of information interaction with other application information systems, providing technical support for power distribution network dispatching and production management. The "feeder automation" function of the existing power distribution automation master station system can only realize automatic recovery of power supply in the non-fault area when a single power distribution line fails, and does not have the load transfer capacity of 10kV line when the whole station is powered off; the existing "load transfer" function can only generate a load transfer plan for a single device, and cannot generate a load transfer scheme for the whole station, the whole bus and multiple lines, nor can it edit the load transfer scheme.

[0056] As shown in Figure 1 The present application provides a power distribution network load transfer method, comprising the following steps:

[0057] S1, obtaining a distribution network fault signal, wherein the fault signal includes bus voltage, main transformer low-voltage side switch, each outgoing line current and main transformer protection signal;

[0058] S2, after the fault signal meets the preset conditions, collect the load section data of the leading line and the transferred line, eliminate the situation where the line cannot serve as the leading line, and obtain several transfer plans with priority;

[0059] S3, based on the preset load transfer mode, perform load transfer according to the transfer plan.

[0060] like Figure 2 As shown, in step S1, the preset conditions include a start condition and a lock condition, and the start condition and the lock condition are judged in sequence.

[0061] like Figure 3 As shown, the starting conditions are specifically:

[0062] All 10kV buses in the substation lose power, meaning the voltage transformers on buses I and II detect that all three phases are zero.

[0063] The 10kV outgoing line topology of the substation loses power, that is, all outgoing lines have no voltage and no current;

[0064] There is no current in the low-voltage side switch of the main transformer, that is, there is no voltage and no current in the busbar incoming line.

[0065] The above three starting conditions must be met at the same time.

[0066] The locking conditions are as follows:

[0067] (1) 10kV outgoing line protection action signal. The 10kV outgoing line has a protection action signal, but the switch does not trip. This is because the line protection has failed to operate. If load transfer is performed, the fault point will be transferred to the lead line, causing the lead line to trip.

[0068] (2) Main transformer backup protection action signal. If the main transformer has a backup protection action signal, it means that the fault is in the busbar or the protection device refuses to operate. If the busbar is reversed, the load transfer will fail and the power outage will be further expanded.

[0069] (3) Exit the entire station channel. If all network communications are interrupted or a remote motor fails, the entire station channel will be exited. At this time, the distribution automation master station system cannot obtain the substation's three remote control information in real time. The information is unreliable, so load transfer is prohibited.

[0070] (4) Remote opening of the low-voltage side switch of the main transformer. If the power is lost due to the operation or troubleshooting by the dispatcher, this function should be locked and not activated.

[0071] If any of the above signals appears, the transfer does not start. In addition, the anti-misoperation lock of the system needs to be considered to prevent the system from malfunctioning due to the misoperation of automation information, non-refreshing or mutation of telemetry data, abnormal failure of the field automation terminal, and the like.

[0072] In step S2, time coordination with the upper-level line protection needs to be considered to effectively avoid the confusion of the upper-level and lower-level actions. The priority of the present scheme is lower than the reclosing of the upper-level power supply (the time limit is generally 2 s) and the action of the backup power supply (the time limit is generally within 8 s), and only when the above time is avoided and the starting condition is met, the system determines that the bus has been de-energized. Considering the action time of the primary device, the starting action time limit can be set to 10 s, or the determination time limit of the starting condition is set to 10 s or more, that is, the main transformer low-voltage side, the bus, and the outgoing line are without voltage and current for 10 s or more, and then the transfer action is considered to be started.

[0073] In step S2, the cases in which the line cannot be used as the carrying line include:

[0074] 1) The transfer operation switch or the transfer path is not allowed to be used as the carrying line;

[0075] 2) The quality code of the tie switch is double-bit error (bad data);

[0076] 3) The line has a single-phase ground fault or the feeder automation fault is not processed and ended;

[0077] 4) The switch position on the transfer path is in the split position or without voltage;

[0078] 5) The operation switch is offline, the working condition is exited, or it is not actually measured.

[0079] After the preset conditions for the transfer action are met, the state of the tie switch at the different station, the operating mode of the related line, and the like are verified, and the transfer channel is generated. For example, the tie switch at the different station is a non-intelligent, intelligent hanging lock remote control signboard, or the intelligent is offline, the tie line at the different station has a ground or a feeder automation display fault that is not processed and ended, and the like, and all of them cannot be used as the carrying line. (If the load of the A line is transferred to the B line for power supply, the A line is the transferred line, the B line is the carrying line, and the power supply side of the B line is referred to as the carrying power supply).

[0080] The priority of the load transfer strategy is as follows:

[0081] (1) If there are multiple carrying lines for one transferred line, the transfer path preferentially selects the carrying path of the traditional power supply, and tries not to use the path in which the distributed power supply participates in the recovery of power supply;

[0082] (2) The priority is determined according to the size of the residual capacity (openable capacity) of the carrying line. The larger the openable capacity is, the higher the priority is, and the openable capacity with the highest priority is selected as the path for the transfer bus. The calculation formula of the openable capacity is as follows.

[0083] The carrying route circuit openable capacity = the carrying route circuit maximum allowable current - the carrying route circuit load current (formula 1).

[0084] (3) The main transformer and the high-voltage side line of the carrying route are considered.

[0085] (4) When the load transfer is performed, the important users, power protection users and livelihood users should be preferentially guaranteed to restore power supply.

[0086] As shown in Figure 4 , in step S3, the process of performing the load transfer is specifically:

[0087] (1) The distribution automation master station remotely controls the opening of each side switch of the main transformer, and isolates the main transformer;

[0088] (2) The distribution automation master station remotely controls the opening of all outgoing line switches of the 10kV bus;

[0089] (3) The remote control contact switch restores the outgoing line of the different station contact (when the whole station is powered off, all lines in the station have lost power, and when the transfer scheme is generated, the topology and live conditions are traced back, and the mutual contact line in the station will not be used as the carrying route path), and the power is sent to the outgoing line switch;

[0090] (4) The optimal reverse supply bus path is selected to restore the 10kV bus power supply;

[0091] (5) According to the preset order, the outgoing line switches of the non-different station contact line are closed one by one to restore power supply. The load rate of the contact line is calculated in real time before each transfer, and when it approaches the allowable load flow, segmented transfer can be considered to further reduce the power failure range;

[0092] (6) When the maximum supply load capacity is reached or all the transfer is completed, stop the transfer;

[0093] (7) Exit the reclosing of the transferred line, the carrying route line protection and reclosing.

[0094] The load transfer execution mode includes automatic mode and interactive mode. The former is automatically executed according to the execution strategy, and the latter pops up a real-time interactive interface (with auxiliary voice alarm) for manual participation. The distribution network dispatcher and the main network dispatcher verify whether the upper power supply can quickly restore power supply to decide whether to execute the scheme. If the execution is performed, one-key start intelligent transfer scheme or only part of the content can be selected. If the load transfer scheme is not completed, the interactive prompt dispatcher handles it.

[0095] After the execution ends, the transferred line details are popped up, the system automatically calculates the outage interval, the number of outage customers, the total load and other information, and generates a detailed list of outage areas, as shown in Table 1, to facilitate subsequent processing by dispatchers and to help the monitoring command team to communicate with outage customers.

[0096] Serial number Substation Line Outage section Total number of outage zones Total outage load Outage start time Outage duration 1 XX XX XX XX XX XX XX …

[0097] Table 1: Outage Area Detail List

[0098] The above embodiments describe a load transfer method for large-scale power outages caused by power grid failures. In addition, the present scheme is also applicable to daily mode.

[0099] According to the plan or temporary work, set the target device, analyze the affected load, and automatically or manually confirm the safe transfer of the affected load to the new power supply point, and propose a load transfer operation scheme including transfer path and transfer capacity.

[0100] It includes pre-plan generation, pre-plan editing and pre-plan execution. The description of this process is explained in conjunction with the distribution automation system.

[0101] Pre-plan generation: Click the function icon on the system application interface, enter the application, and enter the username and password to ensure safety. Click to enter the pre-plan preparation interface. You can select the plant station through the search box, and select the line, bus and plant station on the plant station expansion page as needed. The corresponding load transfer pre-plan is automatically analyzed and generated. If the operating mode changes, you only need to regenerate the pre-plan.

[0102] Pre-plan editing: Double-click the pre-plan to view all detailed operation steps. This detailed step is generated based on real-time operating mode, tie switch status, allowable current and other information. Dispatchers with permission can perform pre-plan editing, pre-plan deletion, priority elevation / lowering and other operations on the popped-up plan. For example, if there are multiple transfer channels for a line, they will be sorted in order of load rate from small to large. The smaller the load rate, the higher the priority. Dispatchers can right-click to change the priority and select the transfer channel. For multiple line load transfers in the plan, the system will generate an operation sequence based on the principle of priority power supply for important users, power protection users and people's livelihood users. Dispatchers can select which lines to transfer first.

[0103] Pre-plan execution is divided into two parts: pre-plan verification and pre-plan execution.

[0104] Pre-plan verification. Before executing the remote control operation command, the pre-plan will be verified. The verification content includes:

[0105] ① Remote signal quality code verification. Identify whether the remote signal quality code of all remote control switches in the transfer pre-plan is normal. If the remote control switch is offline or has a closed lock remote control sign, the verification will not pass.

[0106] ②Transfer mode verification, power supply point tracking is performed on the transfer line and the line with the line, and it is calculated and judged whether the two lines have a loop phase angle difference. Intelligent loop power adjustment (hot reverse) or power adjustment (cold reverse) mode selection; For lines that do not allow loop across regions, trace back to the 220kV bus of the transfer line and the line with the line through topological analysis, and determine whether it is the same power grid partition according to the partition maintained by the 220kV bus. Different power grid partition line transfer load, push cold reverse mode, and the same power grid partition line transfer load uses hot reverse mode.

[0107] ③Safety verification, if the switch remote signaling quality code on the transfer path is in the off position or grounded, the verification will not pass.

[0108] If there are multiple schemes for a line, they are marked with " ". When verifying, if the first scheme fails, the second scheme will be verified. The successful scheme is marked in green, and the failed one is marked in red. Only the verified scheme can be displayed on the "execute plan" page.

[0109] In the execution plan part, remote control mode selection can be performed, which can be "single step execution", "sequential execution", and "concurrent execution". Single step execution requires the operator to confirm each line transfer before execution; sequential execution transfers multiple lines in sequence; concurrent execution transfers multiple lines simultaneously. After verification, the operator can flexibly choose any transfer mode according to the actual situation to quickly transfer the load. The successful steps are marked in green, and the failed ones are marked in red. In addition, the number of remote control failure operations can be set during remote control execution; to ensure safety, only when the switch remote signaling and current telemetry signal change, the switch execution is considered successful.

[0110] According to the method described in the above embodiment, in a new generation of power distribution automation master station system, as shown in Figure 5 , a typical 110kV "single transformer" substation is selected to verify the reliability and accuracy of the technology under various fault conditions. In the figure, there are 10 10kV lines in Junbu station, of which 4 10kV lines can be pulled out, and Junwang line and Chaijia line are connected as non-intelligent devices, which need on-site personnel to operate. The transfer connection table is shown in Table 2.

[0111]

[0112] Table 2 Junbu station and external station connection table

[0113] Daily mode verification:

[0114] Assuming that the No. 1 main transformer of Junbu Station will be overhauled, the 10kV load needs to be transferred out before the overhaul. Enter the pre-plan interface, select Junbu Station, generate the full-station transfer scheme, edit and confirm the scheme, check and pass, select one-key full-automatic execution, and the entire load transfer scheme is successfully executed in only 2 minutes.

[0115] Large-area power failure mode verification:

[0116] 1. Main transformer main protection action test

[0117] On May 24, 2022, at 17:10, the differential protection action of No. 1 main transformer of Junbu Station was set, the line current section value was as shown in Table 2, and the simulation result was as shown in Figure 6 , wherein:

[0118] (1) 10kV Yibaitong line (user private line) power failure;

[0119] (2) 10kV Wen Zhuang line load transfer to Dongwang Station 10kV Baohua line power supply;

[0120] (3) 10kV Dazhai line load transfer to Daliu Station 10kV Guanzhuang line power supply;

[0121] (4) 110kV Ningjia Station 10kV Ninghong line through Xiushui line to supply 10kV Chang'an line, Shenjia line, Beiji line, Wannan line, Changqing line, Junwang line;

[0122] (5) Since Chaijun 00 is a non-intelligent switch, it needs to be operated on site, and 10kV Chaijia line of the standby channel is required.

[0123]

[0124] Table 3 Details of power failure area

[0125] 2. Main transformer low backup protection action test

[0126] Set the low backup protection action of No. 1 main transformer of Junbu Station, and this transfer scheme does not start.

[0127] 3. 10kV outgoing line switch protection action test

[0128] Set the 10kV Chang'an line 011 switch of Junbu Station to the speed section protection action, and the 011 switch is not tripped, the whole station is powered off, and this transfer scheme does not start.

[0129] 4. Full-station channel exit action test

[0130] Exit the channel of Junbu Station, and this transfer scheme does not start.

[0131] 5. Main transformer low-voltage side switch remote opening full-station power failure action test

[0132] The remote control pulls open the 10kV 001 switch of the No.1 main transformer of the military port station, and the transfer supply scheme is not started.

[0133] As shown in Figure 7 The embodiment of the present application also provides a power distribution network load transfer device, which can be deployed in a power distribution automation system, and the device further comprises a signal acquisition module, a transfer processing module, a verification module and a transfer execution module.

[0134] The signal acquisition module is used for acquiring a power distribution network fault signal, and the fault signal comprises a bus voltage, a main transformer low-voltage side switch, each outgoing line current and a main transformer protection signal; the transfer processing module is used for collecting load section data of a line and a transferred line after the fault signal meets a preset condition, excluding a case that cannot be used as a line, and obtaining a plurality of transfer supply schemes with priorities; the verification module is used for performing transfer mode verification and safety verification on the transfer supply schemes; and the transfer execution module performs load transfer according to the transfer supply schemes based on a preset load transfer mode.

[0135] The load transfer device in the embodiment of the present application is realized based on an existing power distribution network automation system.

[0136] Although the specific embodiments of the present application are described above with reference to the drawings, the description is not a limitation on the protection scope of the present application, and those skilled in the art should understand that various modifications or changes made on the basis of the technical solutions of the present application without creative labor are still within the protection scope of the present application.

Claims

1. A method for transferring load in a distribution network, characterized in that: The transfer method comprises the following steps: Obtaining a distribution network fault signal, wherein the fault signal includes bus voltage, main transformer low-voltage side switch, each outgoing line current, and main transformer protection signal; After the fault signal meets the preset conditions, the load section data of the leading line and the transferred line are collected, and the situation where the line cannot serve as the leading line is eliminated to obtain several transfer plans with priority; Based on a preset load transfer mode, performing load transfer according to the transfer plan; The method further includes performing a transfer mode verification and a safety verification on the transfer scheme; The transfer mode verification is specifically as follows: Track the power source points of the transfer line and the power supply line to determine whether there is a phase angle difference between the two lines. Based on the judgment result, select the closed-loop power regulation mode or the power outage power regulation mode; For cross-regional lines that are not allowed to be looped, trace back the 220V busbars of the transfer line and the belt line, and determine whether the transfer line and the belt line are in the same power grid partition based on the partition maintained by the 220V busbar. If so, adopt the loop power regulation mode, otherwise adopt the power outage power regulation mode.

2. The load transfer method of the distribution network according to claim 1, characterized in that: The preset conditions include a start condition and a lock condition, and the start condition and the lock condition are judged in sequence.

3. The load transfer method of the distribution network according to claim 2, characterized in that: The startup conditions are specifically: All busbars in the substation lose power, the 10 kV outgoing line topology of the substation loses power, and there is no current in the low-voltage side switch of the main transformer.

4. The method for transferring load in a distribution network according to claim 2, wherein: The locking conditions are specifically: There is a 10kV outgoing line protection action signal, but the switch does not trip; There is a main transformer backup protection action signal; Exit all station channels; Remote opening of the low-voltage side switch of the main transformer; If any of the above conditions occur, the lockout is triggered.

5. The load transfer method of the distribution network according to claim 1, characterized in that: The situations where a route cannot be used as a guide route include: The transfer operation switch or transfer path is not allowed to be used as a lead line; The quality code of the tie switch is double dislocation; A single-phase grounding fault occurs on the line or a feeder automation fault is not resolved; The switch position on the transfer path is in the open position or no pressure; If any of the above conditions exist, the route cannot be used as a guide.

6. The load transfer method of the distribution network according to claim 1, characterized in that: The process of performing load transfer is specifically as follows: Disconnect the switches on each side of the main transformer to isolate the main transformer; Disconnect all 10kV outgoing switches on the busbar; Restore the outgoing line with inter-station connection through the tie switch and supply power to the outgoing line switch; In order of priority, close the outgoing line switches of the interconnecting lines without different stations one by one to restore power supply. Stop power transfer when the maximum load capacity is reached or all loads have been transferred.

7. A distribution network load transfer device, including and deployable in a distribution automation system, characterized in that: The device further comprises: A signal acquisition module is used to obtain distribution network fault signals, including bus voltage, main transformer low-voltage side switch, each outgoing line current and main transformer protection signal; A power transfer processing module is used to collect load section data of the leading line and the transferred line after the fault signal meets the preset conditions, eliminate the situation where the line cannot serve as the leading line, and obtain several power transfer plans with priority; A load transfer execution module, which executes load transfer according to the load transfer plan based on a preset load transfer mode; The device further includes a verification module, the verification module being used to perform a transfer mode verification and a safety verification on the transfer scheme; The transfer mode verification is specifically as follows: Track the power source points of the transfer line and the power supply line to determine whether there is a phase angle difference between the two lines. Based on the judgment result, select the closed-loop power regulation mode or the power outage power regulation mode; For cross-regional lines that are not allowed to be looped, trace back the 220V busbars of the transfer line and the belt line, and determine whether the transfer line and the belt line are in the same power grid partition based on the partition maintained by the 220V busbar. If so, adopt the loop power regulation mode, otherwise adopt the power outage power regulation mode.

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