Multi-scene power distribution network fault visual self-healing method

Abstract

The invention discloses a multi-scene power distribution network fault visual self-healing method, which comprises the following steps: on the basis of a basic database formed in a basic data collection stage, aiming at the condition of an accident in a corresponding maintenance scene, firstly, monitoring the state of power distribution network equipment in real time according to all calculation results of topology; the method comprises the following steps of: firstly, selecting a line with a relatively large margin and a relatively good comprehensive condition as a reverse tape and transfer line, secondly, considering related conditions, optimizing a transfer path, checking and revising a transfer scheme in a transfer scheme actual control stage, providing all alternative schemes, and providing two reverse power modes of cold reverse and hot reverse during actual control, the method comprises the following steps: automatically generating FA of a back-carrying line and a transfer line and a protection adjustment strategy of a related line, displaying information such as line topology coloring and switching states through a system panoramic contact diagram, recovering a power supply line and highlighting, and finally, automatically finishing fault area isolation and non-fault area power supply recovery, increasing the elasticity of a power grid, ensuring the reliability of power supply, and improving the safety of the power grid. And the electricity utilization perception of customers is improved.

Description

Technical Field

[0001] The present invention relates to the field of power grid dispatching, and in particular to a multi-scenario distribution network fault visualization self-healing method. Background Art

[0002] Extreme events can easily damage distribution networks 110 kV and below, and reliable power supply is crucial for social and economic development. Currently, when a large-scale power outage occurs, controllers must manually develop load transfer plans offline and perform on-site operations to transfer loads. This approach is both time-consuming and labor-intensive, and it fails to tailor optimal load transfer plans to the grid's real-time operating environment and different outage scenarios. Furthermore, it cannot automatically execute these plans and control switches in real time to restore power, resulting in prolonged outages and poor user experience.

[0003] At present, when the main transformer is overloaded, the entire station loses power, the busbar fails, or the busbar is under maintenance, the dispatcher needs to manually search the topology, calculate the load to be transferred, determine the load transfer path, and finally generate a complete load transfer plan, which is time-consuming. In the actual implementation of the plan, the dispatcher needs to give manual phone orders, which takes a long time. In addition, when unexpected situations occur, the re-optimization and formulation of the transfer plan is slow, resulting in a slow power restoration time. In the plan preparation stage, the dispatcher needs to consider the actual load and system operation mode manually, and it takes a long time to manually query the topology and load information of each line, so the plan preparation time is long. In the plan execution stage, the dispatcher's manual phone orders are inefficient, resulting in a long execution time. If the plan needs to be changed due to special circumstances, the preparation steps need to be repeated, which further reduces efficiency and extends the execution time. Summary of the Invention

[0004] In response to the problems existing in the above-mentioned prior art, the present invention provides a multi-scenario distribution network fault visualization self-healing method, which automatically queries relevant line topology and load information, and automatically compiles plans, saving a lot of time in manually searching for various types of information and compiling plans. Assisted execution improves execution efficiency and ensures that the original plan can be quickly changed and optimized under special circumstances.

[0005] Based on the basic database formed during the basic data collection phase, this method addresses accidents such as main transformer overload, upstream power loss, busbar fault, and main transformer or busbar maintenance. First, based on all topology calculation results, the status of distribution network equipment is monitored in real time. Lines with large margins and good overall conditions are selected as reverse and transfer lines. Second, the transfer path is optimized by fully considering various equipment defects, the availability of three-remote switches, and the penetration rate of distributed power sources. Finally, during the actual control phase of the transfer plan, the transfer plan can be reviewed and revised, and all alternative options are provided. During actual control, two power-off modes, cold and hot, are provided, and the FA for reverse and transfer lines and protection adjustment strategies for related lines are automatically generated. A panoramic system connection diagram displays information such as line topology coloring and switch status, with restored power lines highlighted. Ultimately, faulty areas are isolated and power is restored to non-faulty areas.

[0006] The intelligent compilation and actual control method of distribution network transfer plans under multiple application scenarios proposed in the present invention has effectively solved the problem of time-consuming and labor-intensive multi-scenario accident handling mode and the inability to accurately consider the difficulty of plan compilation under the real-time operation environment of the power grid, reduced the load loss under the power grid accident mode, and has certain promotion value.

[0007] To achieve the above objectives, the present invention adopts a technical solution: a multi-scenario distribution network fault visualization self-healing method, comprising the following steps:

[0008] S1. Basic data collection: Search the grid topology connection diagram through the power dispatching control system, dispatch the static data of the technical parameters of all electrical equipment within the jurisdiction, and establish a historical and real-time measurement basic database based on the dynamic data of voltage, current, and protection signals;

[0009] S2. Fault type analysis: Based on the basic database, combined with the power failure scope and the power failure equipment, the fault type is classified;

[0010] S3. Prepare a load transfer plan: Based on a clear assessment of the fault type, ensuring safe power supply and rapidly restoring power, intelligently generate load transfer plans for different fault scenarios.

[0011] S4. Actual control of the power transfer plan: Based on the power transfer plan, the power transfer path is visualized and the power restoration line is highlighted as a reminder.

[0012] Furthermore, the dispatching and control system includes: a smart grid dispatching and control system and a distribution network smart dispatching and control system. The smart grid dispatching and control system is used to monitor and control the operation of the power grid in real time, and the distribution network smart dispatching and control system is used to monitor and control the operation of the distribution network in real time.

[0013] Furthermore, the step S1 specifically comprises the following steps:

[0014] 1.1 Obtain a list of buses in the substation and count the outgoing line switches under the bus. If the bus tie switch between two buses is in the open state, any bus can be used to supply the other bus.

[0015] 1.2 Collect information on the power supply radius, current carrying capacity, operating conditions, tie-switch attributes, and historical maximum loads for the year, the past month, and the past week for all 10kV lines and their tie-lines under the dispatching jurisdiction;

[0016] 1.3 Analysis of the contact line, the definition of the contact switch: a real-time contact switch. When the power supply at both ends of the split switch is different feeders, the split switch is a tie switch;

[0017] 1.4 Topology analysis: Through topology analysis, the communication path between the outgoing line switch under the bus and the outgoing line switch at the opposite end is obtained.

[0018] 1.5 Switch type analysis: Analyze the primary switch. According to the contact path, analyze the primary switch of the distribution network of the outgoing switch and determine whether the primary switch is a three-remote switch. Combined with the contact switch and primary switch type of the outgoing switch, classify the outgoing switch:

[0019] (1) Lines without tie switches;

[0020] (2) The first switch is not a three-way remote control or there is no first switch, but there is communication;

[0021] (3) The primary switch is a three-way remote control, but the contact switch is not;

[0022] (4) The primary switch is a three-way remote control, and the contact switch is a three-way remote control.

[0023] Furthermore, the specific steps of step S2 are as follows: the scenarios in which the power grid needs to perform large-scale load transfer are divided into four types: station-wide power outage, busbar failure, busbar maintenance, and main transformer overload; fault information is collected from the dispatching and control system to determine the type of fault scenario, or the scenario type is manually selected to formulate an accident plan.

[0024] Furthermore, in step S3, a load transfer plan is prepared based on the type selected in S1 and the information collected in S2. Specifically, the steps are as follows:

[0025] 3.1 Calculate and select the line for supplying busbar

[0026] Calculation principles:

[0027] (1) The contact switch is three-remote;

[0028] (2) The line margin is the largest;

[0029] Line margin = opposite-end outgoing line switch current upper limit * coefficient - opposite-end outgoing line switch current value - local-end outgoing line switch current value. The opposite-end outgoing line switch current value is: daily maximum / weekly maximum / monthly maximum / yearly maximum / real-time value; the local-end outgoing line switch current value is: daily maximum / weekly maximum / monthly maximum / yearly maximum / real-time value. Line margin P = OP × F - OC - C.

[0030] Where OP is the upper limit of the switch current of the opposite-end outgoing line switch, F is the load factor, OC is the current value of the opposite-end outgoing line switch, and C is the current value of the local-end outgoing line switch;

[0031] If P ≥ 0, it can be used as an alternative route;

[0032] 3.2 Calculate the lines to be supplied

[0033] The priority of selecting the line to be supplied is as follows:

[0034] (5) For lines without tie switches, the current value set is denoted as C1;

[0035] (6) The first switch is not a three-way remote switch or there is no first switch, and the current value set is recorded as C2;

[0036] (7) If the tie switch is not a three-way remote control, the current value set is recorded as C3;

[0037] (8) The first switch is three-way remote and the tie switch is three-way remote, the current value set is recorded as C4;

[0038] Calculation logic:

[0039] According to the priority of the line to be supplied, the current values ​​of the line outgoing switches are accumulated in sequence to calculate whether the line can be supplied by the designated supply line;

[0040] (5) If ∑C1+∑C2+∑C3+∑C4≤P, then the alternative line can supply all loads under the busbar;

[0041] (6) If ∑C1+∑C2+∑C3+∑C4>P, then the lines without tie switches, the lines with non-three-remote first switches and the lines without first switches need to be supplied by the busbar, and ∑C1+∑C2≤P must be satisfied;

[0042] (7) If the conditions are still not met, try to shed the load by switching on the supply line;

[0043] (8) If the load shedding attempt still fails to meet the supply conditions, the designated line (C1) needs to be unloaded;

[0044] Note: The lines with non-three-remote control (C3) tie switches and three-remote control (C4) primary switches and tie switches can be partially supplied by the opposite end;

[0045] 3.3 Load shedding of power supply lines

[0046] Since the margin of the substitute supply line cannot meet the load of the substitute supply busbar, part of the load of the line at the opposite end of the substitute supply line is transferred through the interconnection line of the opposite end line to release the margin of the opposite end line, thereby increasing the margin of the substitute supply line and meeting the current substitute supply demand;

[0047] 3.4 Supply to other end

[0048] For lines that cannot be restored through busbar power supply, the opposite line will provide power. Since there may be multiple opposite-end interconnection lines, the selection of the opposite-end line is based on the following principles:

[0049] (1) The margin of the opposite end line meets the supply demand;

[0050] (2) Prioritize the circuit breaker with three remote controls;

[0051] 3.5 In the event of a total station power outage, busbar reverse transmission lines are selected. Taking the 10 kV busbar as the power supply unit, distribution lines are comprehensively ranked based on power supply radius, line current carrying capacity, original line load, and whether the tie switch is a three-remote switch. This creates a reverse transmission line ranking table. After the reverse transmission line is selected, the remaining lines are routed out using a cold reverse method, that is, first pulling the substation switch, then closing the distribution network tie switch to restore power.

[0052] 3.6 In the event of a busbar failure, if the busbar is not in operation, a transfer plan must be provided for all lines that can transfer power, and the remaining lines must be shut down. When transferring power, a cold shutdown method should be used;

[0053] 3.7 In the event of busbar maintenance, a power transfer plan must be provided for all lines that can be transferred, and the remaining lines must be shut down. When transferring power, a hot-swap method should be adopted, that is, first closing the distribution network interconnector and then opening the substation switch. If there is a distributed photovoltaic line outgoing from the outage busbar, the photovoltaic system should be notified to decouple and the substation switch of the line should be opened.

[0054] 3.8 In case of main transformer overload, the dispatcher shall input the load to be transferred and provide a transfer plan for all transferable lines. When transferring, the hot-reverse method shall be adopted.

[0055] Furthermore, when reversing the power supply of the distribution network, the status of the distribution network equipment should be monitored in real time, and the defects of various equipment should be considered to optimize the selection of the transfer path. When selecting the transfer path, the three-remote distribution network switch should be given priority. When formulating the plan, a 10% margin should be left for the load rate of the reverse line and the transfer line, and the penetration rate of distributed power sources should be fully considered. The actual load should include the load supplied by the connected distributed power sources.

[0056] In the scenario of total station power outage and main transformer overload, after all transferable lines have been transferred, there will still be a power shortage. In addition to providing the transfer plan and operation switch information of all transfer lines, the power shortage and power outage line information after the transfer, as well as the power outage line operation plan, must also be provided;

[0057] Make corresponding adjustments to the feeder automation FA mode, reclosing and protection; FA adjustment requires a lot of operations, so in order to quickly realize FA mode switching, a FA mode adjustment assistant is developed; this assistant establishes a mapping relationship between eight common application scenarios and FA execution strategies, realizing one-click switching of line FA mode execution strategies.

[0058] Furthermore, the step S4 specifically comprises the following steps:

[0059] 4.1 The dispatcher can choose between two modes: automatic execution and item-by-item execution;

[0060] 4.2 Operation of the outgoing line switch of the substation. When generating the power transfer plan, if the type is selected as total station power failure or busbar failure, the outgoing line switch of the substation will be given a control signal by the distribution automation system;

[0061] If the type is selected as busbar maintenance or main transformer overload, the substation outgoing line switch is operated by monitoring; the call order items that require monitoring operation are transferred to the OMS system to generate an operation ticket; during the operation, operation information is collected in real time;

[0062] 4.3 If the interconnecting switch of a certain transfer line is not a three-remote switch, the operation will be transferred to the OMS system to generate an operation ticket; during the operation, the operation information will be collected in real time;

[0063] 4.4 During the operation, the operation interface can monitor the bus voltage of the substation involved, the load rate of the transfer and reverse lines, and the power supply status of the line load in real time;

[0064] 4.5 During the actual control process, in addition to the operation interface, a wiring diagram visualization interface is launched; when operating a certain line, the line becomes brighter, and the switch position information can be collected and set in real time;

[0065] 4.6 The plan can be adjusted in real time. During the execution process, if an operation fails, the reason for the failure and the backup plan of the operation will be given. The dispatcher will decide whether to execute the backup plan. If not, the next step will be skipped. During the entire plan execution process, the dispatcher can decide whether to recalculate. If recalculation is chosen, a new plan will be generated according to the actual method for operation;

[0066] 4.7 Operation records can be synchronized to the OMS dispatch log power grid accident module. After the plan is executed, the historical records can be queried.

[0067] The beneficial effects of the present invention are: this method fully considers four different application scenarios, and proposes scenario identification, plan preparation, and time control methods for each scenario; it can automatically analyze the transfer line topology and load conditions, and fully consider the controllable reliability of the distribution network equipment, give priority to relying on three remote switches, give priority to lines with good operating conditions and short power supply paths, avoid defective equipment, and quickly and intelligently generate load transfer plans; during the plan execution stage, the dispatcher can control the execution in real time, and can change the plan execution order or generate a new plan in real time according to the on-site situation, and the plan execution is fast and flexible; the time for restoring power supply after a large-scale power outage can be shortened from hours to minutes, greatly improving the user's power consumption experience; this method increases the flexibility of the power grid, ensures power supply reliability, and improves customers' power consumption perception. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 It is a schematic diagram of the process of the present invention;

[0069] Figure 2 Schematic diagram of the calculation process in step 3.2;

[0070] Figure 3 This is the Xiaqiao substation 10kV 1 busbar outgoing line and its connection diagram;

[0071] Figure 4 This is the load transfer scheme diagram for 10kV1 busbar of 35kV Xiaqiao substation;

[0072] Figure 5 This is the actual control interface diagram of the Xiaqiao power supply transfer plan;

[0073] Figure 6 This is the visualization interface diagram of the Xiaqiao transformer wiring diagram. DETAILED DESCRIPTION

[0074] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0075] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention pertains. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0076] Distribution automation technology can effectively solve the problems of rapid isolation of fault points and rapid power restoration in non-fault areas in the event of power grid failure. However, due to the current dispersion of fault signals and insufficient fusion of multi-source data elements in the handling of large-scale power outages, complex faults and derivative faults, a single fault automation handling method is still adopted, and there is a lack of preparation of power transfer plans and visual control methods for multi-scenario distribution network faults.

[0077] D5000 system: The D5000 system is a smart grid dispatching and control system that can monitor and control grid operations in real time. D5200 system: The D5200 system is a distribution network smart dispatching and control system that can monitor and control distribution network operations in real time. FA (Feeder Automation) is an automation system that monitors, coordinates, and controls equipment on distribution lines in real time. It can automatically detect and isolate faulty sections and quickly restore power to non-faulty sections, improving power supply reliability and power quality.

[0078] Based on the application of automation technology, the present invention provides a multi-scenario distribution network fault visualization self-healing method, such as Figure 1 As shown, it mainly includes the following steps:

[0079] S1. Basic data collection: In the D5000 and D5200 systems, search for grid topology connection diagrams, dispatch static data such as technical parameters of all electrical equipment within the jurisdiction, and establish a historical and real-time measurement database for dynamic data such as voltage, current, and protection signals;

[0080] S1 specific steps:

[0081] 1.1 Obtain a list of buses in the substation and count the outgoing line switches under each bus. If the bus tie switch between two buses is in the open state, any bus can be used to supply the other bus.

[0082] 1.2 Collect information on the power supply radius, current carrying capacity, operating conditions, tie-switch attributes, and historical maximum loads for the year, the past month, and the past week for all 10kV lines and their tie-lines under the dispatching jurisdiction;

[0083] 1.3 Analysis of the contact line: Definition of contact switch: real-time contact switch. When the power supply at both ends of the split switch is different feeders, the split switch is a tie switch;

[0084] The main distribution network equipment is modeled by the connection point number. The graph model GM can be represented by a triple, GM=<N,R,L> Where N = {n1, n2, ... nt} is a non-empty finite number of node sets, and t represents the number of nodes;

[0085] R = {r1, r2, ...rs} is a relationship set consisting of ordered node pairs (ni, nj) in the node set N. The s elements in R are called s relations and satisfy

[0086] L is a set of node attributes and relationship attributes;

[0087] Through the topological analysis of the graph model, the communication path between the outgoing line switch under the bus and the outgoing line switch at the opposite end is obtained;

[0088] 1.4 Topology analysis: Through topology analysis, the communication path between the outgoing line switch under the bus and the outgoing line switch at the opposite end is obtained;

[0089] 1.5 Switch type analysis: Analyze the primary switch. Based on the connection path, analyze the primary switch of the distribution network of the outgoing switch and determine whether the primary switch is a three-remote switch. Combined with the connection switch and primary switch type of the outgoing switch, classify the outgoing switch:

[0090] (1) Lines without tie switches;

[0091] (2) The first switch is not a three-way remote control or there is no first switch, but there is communication;

[0092] (3) The primary switch is a three-way remote control, but the contact switch is not;

[0093] (4) The primary switch is a three-way remote control, and the contact switch is a three-way remote control.

[0094] S2. Fault Type Analysis: Based on the basic database, the fault type is classified in combination with the power outage scope and the power-lost equipment. Scenarios requiring large-scale load transfer are categorized into four types: station-wide power outage, busbar failure, busbar maintenance, and main transformer overload. Fault information is collected from the D5000 and D5200 systems to determine the fault scenario type, or a scenario type can be manually selected for accident response planning.

[0095] S3. Prepare a load transfer plan: Based on a clear assessment of the fault type, ensuring safe power supply and rapidly restoring power, intelligently generate load transfer plans for different fault scenarios.

[0096] S3: Prepare a load transfer plan based on the type selected in S1 and the information collected in S2. The specific steps are as follows:

[0097] 3.1 Calculate and select the line for supplying busbar

[0098] Calculation principles:

[0099] (1) The contact switch is three-remote;

[0100] (2) The line margin is the largest;

[0101] Line margin = switch current upper limit of the outgoing line switch at the opposite end * coefficient - current value of the outgoing line switch at the opposite end (optional: daily maximum / weekly maximum / monthly maximum / yearly maximum / real-time value) - current value of the outgoing line switch at the local end (optional: daily maximum / weekly maximum / monthly maximum / yearly maximum / real-time value);

[0102] Line margin P = OP × F - OC - C;

[0103] Where OP is the upper limit of the switch current of the opposite-end outgoing line switch, F is the load factor, OC is the current value of the opposite-end outgoing line switch, and C is the current value of the local-end outgoing line switch;

[0104] If P ≥ 0, it can be used as an alternative route;

[0105] 3.2 Calculate the lines to be supplied

[0106] The priority of selecting the line to be supplied is as follows:

[0107] (9) For lines without tie switches, the current value set is denoted as C1;

[0108] (10) The first switch is not a three-way remote switch or there is no first switch, and the current value set is recorded as C2;

[0109] (11) If the tie switch is not a three-way remote control, the current value set is recorded as C3;

[0110] (12) The first switch is a three-way switch and the tie switch is a three-way switch. The current value set is recorded as C4.

[0111] like Figure 2 As shown, the calculation logic is:

[0112] According to the priority of the line to be supplied, the current values ​​of the line outgoing switches are accumulated in sequence to calculate whether it can be supplied by the designated supply line.

[0113] (9) If ∑C1+∑C2+∑C3+∑C4≤P, then the alternative line can supply all loads under the busbar;

[0114] (10) If ∑C1+∑C2+∑C3+∑C4>P, then the lines without tie switches, the lines with non-three-remote first switches and the lines without first switches need to be supplied by the busbar, and ∑C1+∑C2≤P must be satisfied;

[0115] (11) If the conditions are still not met, try to shed the load by switching on the supply line;

[0116] (12) If the load shedding attempt still fails to meet the supply conditions, it is necessary to specify the line (C1) to lose the load.

[0117] Note:

[0118] The lines where the tie switch is not three-remote (C3) and the first switch is three-remote and the tie switch is three-remote (C4) can be partially supplied by the opposite end.

[0119] 3.3 Load shedding of power supply lines

[0120] Since the margin of the substitute supply line cannot meet the load of the substitute supply bus, part of the load of the line at the opposite end of the substitute supply line is transferred to the substitute supply line through the connecting line of the opposite end line to release the margin of the opposite end line, thereby increasing the margin of the substitute supply line and meeting the current substitute supply demand.

[0121] 3.4 Supply to other end

[0122] For lines that cannot be restored through busbar power supply, the opposite line can be used to provide power. Since there may be multiple opposite-end connection lines, the selection of the opposite-end line should follow the following principles:

[0123] (1) The margin of the opposite end line meets the supply demand

[0124] (2) Prioritize the circuit breaker with three remote controls

[0125] 3.5 In the event of a complete station power outage, busbar reverse transmission lines are selected. Using the 10kV busbar as the power supply unit, distribution lines are ranked comprehensively based on factors such as power supply radius, line current carrying capacity, original line load, and whether the tie switch is a three-remote switch. This creates a reverse transmission line ranking table. After the reverse transmission line is selected, the remaining lines are routed using a cold reverse method, that is, first pulling the substation breaker, then closing the distribution network tie switch to restore power.

[0126] 3.6 In the event of a busbar failure, if the busbar is no longer operational, a transfer plan must be developed for all available lines, with the remaining lines shut down. A cold shutdown method should be used when transferring power.

[0127] 3.7 During busbar maintenance, a plan must be developed for all lines capable of transferring power, with all other lines shut down. A hot-swap method should be used during transfer: first close the distribution network interconnector, then open the substation breaker. If a distributed photovoltaic line is connected to the outage busbar, the photovoltaic system should be disconnected and the substation breaker for that line should be opened.

[0128] 3.8 In case of main transformer overload, the dispatcher shall input the load to be transferred and provide a transfer plan for all transferable lines. When transferring, the hot-reverse method shall be adopted.

[0129] When implementing a power reversal on the distribution network, the status of distribution network equipment should be monitored in real time, and defects in various types of equipment should be considered to optimize the transfer path selection. When selecting a transfer path, priority should be given to three-remote distribution network switches. When formulating the plan, a 10% margin should be allowed for the load factor of the reversal and transfer lines, and the penetration rate of distributed power sources should be fully considered. The actual load should include the load supplied by the connected distributed power sources.

[0130] In the scenario of total station power outage and main transformer overload, there will still be a power shortage after all transferable lines have been transferred. In addition to providing the transfer plan, operating switches and other information of all transfer lines, it is also necessary to provide the power shortage and power outage line information after the transfer, as well as the power outage line operation plan.

[0131] Adjust the feeder automation (FA) mode, reclosing, and protection accordingly. FA adjustments require extensive operations and, if performed manually, can be time-consuming. To quickly switch FA modes, an FA Mode Adjustment Assistant was developed. This assistant maps eight common application scenarios to FA execution strategies, enabling one-click switching of line FA execution strategies. Specific feeder automation mode adjustments are shown in Table 1, and reclosing and protection adjustments are shown in Table 2.

[0132] Table 1 Busbar series supply FA adjustment method

[0133]

[0134] Table 2 Busbar series supply reclosing and protection adjustment mode

[0135]

[0136] S4. Control the power transfer plan. Based on the power transfer plan, the power transfer path is visualized and the restored power line is highlighted as follows:

[0137] 4.1 The dispatcher can choose between two modes: automatic execution and item-by-item execution;

[0138] 4.2 Operation of the outgoing line switch of the substation. When generating the power transfer plan, if the type is selected as total station power failure or busbar failure, the outgoing line switch of the substation will be given a control signal by the distribution automation system;

[0139] If the type is selected as busbar maintenance or main transformer overload, the substation outgoing line switch is operated by monitoring; the call order items that need monitoring operation are transferred to the OMS system to generate an operation ticket. During the operation, the operation information is collected in real time;

[0140] 4.3 If the interconnecting switch of a certain transfer line is not a three-remote switch, the operation will be transferred to the OMS system to generate an operation ticket; during the operation, the operation information will be collected in real time;

[0141] 4.4 During the operation, the operation interface can monitor the bus voltage of the substation involved, the load rate of the transfer and reverse lines, and the power supply status of the line load in real time;

[0142] 4.5 During the actual control process, in addition to the operation interface, a wiring diagram visualization interface is launched; when operating a certain line, the line becomes brighter, and the switch position information can be collected and set in real time;

[0143] 4.6 The plan can be adjusted in real time. During the execution process, if the operation fails, the reason for the failure will be given, and an alternative plan for the operation will be given. The dispatcher will decide whether to execute the alternative plan. If the alternative plan is not executed, the execution will be skipped. During the entire plan execution process, the dispatcher can decide whether to recalculate. If recalculation is chosen, a new plan will be generated according to the actual method and the operation will be carried out.

[0144] 4.7 Operation records can be synchronized to the OMS dispatch log power grid accident module. After the plan is executed, the history records can be queried.

[0145] like Figure 3 As shown in the figure, taking the power outage of the entire Xiaqiao substation as an example, a large-scale power outage plan was prepared;

[0146] Table 3 Xiaqiao Substation 10kV 1 busbar outgoing line reverse sequence table

[0147]

[0148] In addition, when a busbar fault occurs or part of the line needs to be transferred due to power shortage, if there are two or more connecting lines to be transferred, the transfer path of the line needs to be selected. Taking the 10kV 1 busbar outgoing line of Xiaqiao substation as an example, the transfer path order of the transfer line is shown in Table 4.

[0149] Table 4 Xiaqiao Substation 10kV Busbar 1 Outgoing Line Connection Sequence

[0150]

[0151] The final power supply transfer plan for Xiaqiao Substation is as follows Figure 4 In addition, the solution can be exported on the Web, and the output format is shown in Table 5.

[0152] Table 5 Load transfer scheme output interface

[0153]

[0154] Xiaqiao transformer actual control interface is as follows Figure 5 As shown, in the actual control process, in addition to the operation interface, a wiring diagram visualization interface should be launched, such as Figure 6 As shown, when a line operation is being performed, the line becomes brighter, and switch position information is collected and set in real time. The operation record can be synchronized to the OMS dispatch log power grid accident module. After the plan is executed, the historical records can be queried.

[0155] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A multi-scenario distribution network fault visualization self-healing method, characterized in that: The steps include: S1. Basic data collection: Search the topological connection diagram of the power grid through the power dispatching control system, dispatch the static data of technical parameters of all electrical equipment within the jurisdiction, and establish a historical and real-time measurement basic database based on the dynamic data of voltage, current and protection signals; S2. Fault type analysis: Based on the basic database, combined with the power failure scope and the power failure equipment situation, the fault type is classified; S3. Prepare a power transfer plan: On the premise that the fault type is clearly identified, with safe power supply as the premise and rapid power restoration as the goal, intelligently generate a load transfer plan for different fault scenarios; S4. Actual control of the power transfer plan: Based on the power transfer plan, the power transfer path is visualized and the power restoration line is highlighted.

2. According to claim 1, a multi-scenario distribution network fault visualization self-healing method is characterized in that: The dispatching and control system includes: a smart grid dispatching and control system and a distribution network smart dispatching and control system. The smart grid dispatching and control system is used to monitor and control the operation of the grid in real time, and the distribution network smart dispatching and control system is used to monitor and control the operation of the distribution network in real time.

3. According to the multi-scenario distribution network fault visualization self-healing method of claim 1, it is characterized in that: The specific steps of step S1 are as follows: 1.1 Obtain the busbar list in the substation and count the outgoing line switches under the busbars. If the busbar tie switch between two busbars is in the open state, any busbar can be used to supply the other busbar; 1.2 Collect the power supply radius, current carrying capacity, operating conditions, interconnection switch attributes, and historical maximum load information for the current year, the past month, and the past week for all 10kV lines and their interconnection lines under the dispatching jurisdiction; 1.3 Analysis of the contact line, the definition of the contact switch: real-time contact switch, when the power supply at both ends of the split switch is different feeders, the split switch is a contact switch; 1.4 Topology analysis: Through topology analysis, the communication path between the outgoing line switch under the bus and the outgoing line switch at the opposite end is obtained. 1.5 Switch type analysis: Analyze the primary switch. According to the contact path, analyze the primary switch of the distribution network of the outgoing switch, and obtain whether the primary switch is a three-remote switch. Combined with the contact switch and the primary switch type of the outgoing switch, classify the outgoing switch: (1) Lines without tie switches; (2) The first switch is not a three-way remote control or there is no first switch, but there is communication; (3) The primary switch is a three-way remote control, but the contact switch is not a three-way remote control; (4) The primary switch is a three-way remote control and the contact switch is a three-way remote control.

4. According to claim 1, a multi-scenario distribution network fault visualization self-healing method is characterized in that: The specific steps of step S2 are as follows: the scenarios where the power grid needs to perform large-scale load transfer are divided into four types: station-wide power outage, bus failure, bus maintenance, and main transformer overload; fault information is collected from the dispatching and control system to determine the type of fault scenario, or the scenario type is manually selected to formulate an accident plan.

5. According to the multi-scenario distribution network fault visualization self-healing method of claim 1, it is characterized in that: The step S3 prepares a load transfer plan according to the type selected by S1 and the information collected by S2, and the specific steps are: 3.1 Calculate and select the line for the substitute busbar Calculation principle: (1) The contact switch is three-remote; (2) The line margin is the largest; Line margin = switch current upper limit of the outgoing line switch at the opposite end * coefficient - current value of the outgoing line switch at the opposite end - current value of the outgoing line switch at the local end, where the outgoing line switch current value at the opposite end: daily maximum / weekly maximum / monthly maximum / yearly maximum / real-time value, and the outgoing line switch current value at the local end: daily maximum / weekly maximum / monthly maximum / yearly maximum / real-time value; Line margin P = OP × F-OC-C; Where OP is the upper limit of the switch current of the opposite-end outgoing line switch, F is the load factor, OC is the current value of the opposite-end outgoing line switch, and C is the current value of the local-end outgoing line switch; If P ≥ 0, it can be used as an alternative route; 3.2 Calculate the lines to be supplied The priority of selecting the line to be replaced is as follows: (1) For lines without tie switches, the current value set is denoted as C1; (2) The first switch is not a three-way remote switch or has no first switch, and the current value set is recorded as C2; (3) The tie switch is not three-way remote control, and the current value set is recorded as C3; (4) The primary switch is a three-way switch and the tie switch is a three-way switch, and the current value set is recorded as C4; Calculation logic: According to the priority of the line to be supplied, the current values ​​of the line outgoing switches are accumulated in sequence to calculate whether the line can be supplied by the designated supply line; (1) If ∑C1+∑C2+∑C3+∑C4≤P, then the alternative line can supply all loads under the bus; (2) If ∑C1+∑C2+∑C3+∑C4>P, then the line without tie switch, the first switch is non-three-remote and no first switch The related lines need to be supplied by the busbar and need to satisfy ∑C1+∑C2≤P; (3) If the conditions are still not met, try to shed the load by switching on the supply line; (4) If the load shedding attempt still fails to meet the supply conditions, the specified line (C1) needs to be unloaded; Note: The lines with non-three-remote control (C3) tie switches and three-remote control (C4) primary switches can be partially supplied by the opposite end; 3.3 Load shedding of power supply lines Since the margin of the substitute supply line cannot meet the load of the substitute supply busbar, part of the load of the line at the opposite end of the substitute supply line is transferred through the contact line of the opposite end line to release the margin of the opposite end line, thereby increasing the margin of the substitute supply line and meeting the substitute supply demand this time; 3.4 Supply to other end For lines that cannot be restored through busbar supply, the opposite line of the line will be used for supply. Since there may be multiple opposite-end contact lines, the selection of the opposite-end line is based on the following principles: (1) The margin of the opposite end line meets the demand for power supply; (2) Priority should be given to lines with three-remote interconnection switches; 3.5 In the case of power outage of the entire station, the busbar reverse line is selected. The 10 kV busbar is used as the power supply unit. The distribution lines are comprehensively sorted according to the power supply radius, line current carrying capacity, original line load, and whether the connecting switch is a three-remote switch to form a reverse line ranking table; after the reverse line is selected, the remaining lines are derived in a cold reverse manner, that is, the substation switch is pulled first, and then the distribution network connecting switch is closed to restore power; 3.6 In case of busbar failure, the busbar is not in operation condition, and a transfer plan for all the lines that can be transferred must be given, and the other lines will be shut down; when transferring, a cold shutdown method should be adopted; 3.7 In case of busbar maintenance, a transfer plan for all transferable lines shall be given, and the remaining lines shall be shut down. When transferring, a hot reversal method shall be adopted, that is, first close the distribution network contact switch, and then pull the substation switch. If there is a distributed photovoltaic line outgoing from the power outage busbar, the photovoltaic power generation shall be notified to be de-listed, and the substation switch of the line shall be opened. 3.8 In case of main transformer overload, the dispatcher shall input the load to be transferred and provide a transfer plan for all the lines that can be transferred. When transferring, the hot transfer method should be adopted.

6. A multi-scenario distribution network fault visualization self-healing method according to claim 5, characterized in that: When reversing the power supply of the distribution network, the status of the distribution network equipment should be monitored in real time, the defects of various equipment should be considered, and the selection of the transfer path should be optimized; when selecting the transfer path, the three-remote distribution network switch should be given priority; when formulating the plan, a 10% margin should be left for the load rate of the reverse line and the transfer line, and the penetration rate of distributed power sources should be fully considered. The actual load should include the power supply load of the connected distributed power sources; In the scenario of power outage of the entire station and overload of the main transformer, after all transferable lines have been transferred, there is still a power shortage. In addition to the transfer plan and operation switch information of all transfer lines, the power shortage and power outage line information after the transfer, as well as the power outage line operation plan, should also be given; Make corresponding adjustments to the feeder automation FA mode, reclosing and protection; FA adjustment requires a lot of operations, and in order to quickly realize FA mode switching, a FA mode adjustment assistant is developed; the assistant establishes a mapping relationship between eight common application scenarios and FA execution strategies, and realizes one-click switching of line FA mode execution strategies.

7. According to claim 1, a multi-scenario distribution network fault visualization self-healing method is characterized in that: The specific steps of step S4 are as follows: 4.1 The dispatcher can choose between two modes: automatic execution and item-by-item execution; 4.2 Operation of the outgoing line switch of the substation. When the power transfer plan is generated, if the type is selected as the whole station power failure or bus failure, the outgoing line switch of the substation will be given a control signal by the distribution automation system; If the type is selected as busbar maintenance or main transformer overload, the substation outgoing line switch is operated by monitoring; the order items that need monitoring operation are transferred to the OMS system to generate an operation ticket; during the operation, the operation information is collected in real time; 4.3 If the interconnecting switch of a transfer line is not a three-remote switch, the operation will be transferred to the OMS system to generate an operation ticket; during the operation, the operation information will be collected in real time; 4.4 During the operation, the operation interface can monitor the bus voltage of the substation involved, the load rate of the transfer and reverse lines, and the power supply situation of the line load in real time; 4.5 During the actual control process, in addition to the operation interface, a wiring diagram visualization interface is launched; when operating a certain line, the line becomes brighter, and the switch position information can be collected and set in real time; 4.6 The plan can be adjusted in real time. During the execution process, if the operation fails, the reason for the failure is given, and the backup plan for the operation is given. The dispatcher decides whether to execute the backup plan. If the backup plan is not executed, the next plan will be executed. During the execution of the entire plan, the dispatcher can decide whether to recalculate. If recalculation is chosen, a new plan will be generated according to the actual method for operation; 4.7 Operation records can be synchronized to the OMS dispatch log power grid accident module. After the plan is executed, the operation records can be queried in the historical records.

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