Station domain level fault processing method

Abstract

The invention discloses a station domain level fault processing method. In order to solve the problem of limited real-time response capability caused by low processing efficiency when a main transformer N-1 fault and a low-voltage bus fault of a transformer substation are processed in the prior art, the method comprises the steps of monitoring main transformer load and bus voltage operation in an area under administration, identifying the main transformer N-1 fault and classifying the low-voltage bus fault; under a main transformer N-1 fault, adjusting resources by synthesizing main transformer scheduling information to reduce the load rate of a target main transformer, and adopting load transfer and line gap regulation and control step by step for load rate out-of-limit; when a low-voltage bus has a fault, a full-stop and full-transfer process is formulated by combining a topological structure of a feeder line of a main transformer station, and a transfer and resource adjustment mode is adopted step by step according to the fault degree for regulation and control. For a main transformer N-1 fault and a low-voltage bus fault of a transformer substation, transformer substation level resources are preferentially utilized to carry out load regulation, and when necessary, a line gap response module is called to carry out load voltage drop, so that power supply is quickly recovered.

Description

Technical Field

[0001] The present invention relates to the field of substation fault processing, and in particular to a substation-level fault processing method. Background Art

[0002] As the scale of power grids continues to expand and the complexity increases, substations, as key nodes in the power system, are crucial to the safe and stable operation of the entire power grid. During the operation of substations, main transformer N-1 faults and low-voltage bus faults are two common types of faults, which refer to the failure of the low-voltage line to automatically switch to another main transformer for power supply when the main transformer of the substation fails, and the failure of the low-voltage bus to automatically switch power supply when the main transformer or low-voltage bus fails, resulting in a loss of pressure in the low-voltage bus.

[0003] Under existing technical conditions, when a transformer N-1 fault or a low-voltage bus fault occurs in a substation, dispatchers usually need to manually analyze the fault situation and formulate a transfer plan and resource adjustment strategy to ensure that the power supply after the fault is not affected. However, this process often relies on the experience and judgment of dispatchers, which is not only inefficient, but also may have the risk of misjudgment or omission. In addition, since many factors need to be considered in the fault handling process, such as the main transformer load rate, line load rate, etc., traditional processing methods are often difficult to achieve comprehensive optimization and real-time response.

[0004] For example, a method for automatically transferring loads online when a feeding substation is completely shut down, disclosed in Chinese patent literature, has the publication number CN115549309A, and includes (1) detecting characteristic quantities of a feeding substation complete shutdown fault; (2) determining whether a feeding substation complete shutdown fault has occurred; if no feeding substation complete shutdown fault has occurred, returning to step (7); if a feeding substation complete shutdown fault has occurred, continuing to step (3); (3) obtaining data from the main grid control system; (4) obtaining data from the distribution grid control system; (5) updating an execution table for a feeding substation complete shutdown fault handling plan; (6) executing a feeding substation complete shutdown fault power supply recovery procedure; and (7) determining whether the feeding substation complete shutdown fault has been restored. Although this solution covers multiple links such as detection, judgment, data acquisition, updating execution tables and power restoration when dealing with the failure of the feeding substation, it has defects such as insufficient automation and intelligence, inaccurate fault detection and judgment, incomplete and real-time data processing, lack of priority and flexibility in fault handling, insufficient optimization of power restoration procedures, and problems with the accuracy of fault recovery judgment. Further optimization is needed to improve processing efficiency and accuracy. Summary of the invention

[0005] The present invention mainly solves the problem of low processing efficiency and limited real-time response capability in the prior art when processing substation main transformer N-1 fault and low-voltage bus fault; provides a station-level fault processing method, for substation main transformer N-1 fault and low-voltage bus fault, through a one-key optimization processing function, preferentially using substation-level resources for load adjustment, and then adjusting the line operation mode through one-key transfer, and calling the line gap response module for load voltage reduction when necessary, to ensure that the main transformer and line load rate are not overloaded after the fault, and quickly restore power supply.

[0006] The above technical problems of the present invention are mainly solved by the following technical solutions: The present invention includes: monitoring the operation of the main transformer load and bus voltage within the jurisdiction, identifying the main transformer N-1 fault and low-voltage bus fault classification; in the case of main transformer N-1 fault, comprehensively adjusting the resources of the main transformer dispatch information to reduce the target main transformer load rate, and taking step-by-step transfer and line gap control for load rate exceeding the limit; in the case of low-voltage bus fault, combining the topological structure of the feeder line carried by the main transformer to formulate a full stop and full transfer process, and taking step-by-step transfer and resource adjustment methods according to the degree of fault. The present invention monitors the main transformer load and bus voltage, intelligently responds to N-1 faults and low-voltage bus faults, and improves the stability of the power grid and the efficiency of fault response through resource scheduling and transfer strategies.

[0007] Preferably, the main transformer load and bus voltage operating data within the comprehensive monitoring area are calculated to determine the main transformer overload situation. If the number of overloaded main transformers is not less than 1, it is determined that the main transformer N-1 fault occurs. If the number of substations with power outages within the main transformer's jurisdiction is greater than n, the corresponding substation bus voltage loss situation is checked to determine the low-voltage bus fault. An independent module for monitoring the main transformer load status is set. Comprehensively monitor the main transformer load and bus voltage within the jurisdiction, accurately monitor the main transformer load status through an independent module, quickly identify and respond to the main transformer N-1 fault and low-voltage bus fault, and improve the timeliness and accuracy of power grid fault handling.

[0008] Preferably, the main transformer load rate is calculated as follows: read the transformer table, obtain the transformer winding table information through the association relationship, filter and select the low-voltage winding of the target monitoring voltage level, and calculate the current load rate according to "current value i / rated current"; according to the corresponding high-voltage winding, calculate the power load rate according to "active value p / normal rated power of winding". By associating the transformer table and winding table information, the current load rate and power load rate are accurately calculated, the monitoring of the main transformer load rate is optimized, and the reliability and economy of the power grid operation are ensured.

[0009] Preferably, the fault of the main transformer N-1 causes the single transformer to be overloaded and exceeds the limit, and the overload is handled in a hierarchical manner: basic regulation: search for the substation-level adjustable distributed resources under the overloaded main transformer, and reduce the target main transformer load rate by comprehensively considering the current main transformer overload and the adjustable margin of distributed resources; level I regulation: after the basic regulation, if the main transformer load rate is still over the limit, call the line transfer, search for the topological connection of the feeder under the main transformer, and adjust the feeder / main transformer current load transfer; level II regulation: obtain the line gap response of the feeder carried by the main transformer, and adjust the line load to reduce the load of the main transformer. For the overload caused by the fault of the main transformer N-1, a hierarchical processing strategy is used, combined with distributed resource regulation, line transfer and line gap response, to effectively reduce the main transformer load rate and ensure the safe and stable operation of the power grid.

[0010] Preferably, the low-voltage bus fault is adjusted step by step: basic adjustment: analyze the topological structure of the feeder under the main transformer, formulate and verify the full stop and full transfer process in combination with the current load of the feeder, and determine whether all lines can be transferred. If they can be fully transferred, directly execute the plan; advanced adjustment: if the transfer causes some lines to be overloaded, use adjustable distributed resource adjustment, search for line-level distributed resources such as energy storage and adjustable load under the current target line, and perform resource adjustment in the order of energy storage adjustment and load adjustment. The low-voltage bus fault step-by-step adjustment strategy ensures the effectiveness of line transfer through basic full stop and full transfer analysis and advanced distributed resource adjustment, while reducing line overload pressure and improving the fault response capability of the power grid.

[0011] Preferably, the described full stop and full transfer process for low-voltage bus failure in the target substation includes: isolating the faulty bus, acquiring all power-off lines, dividing the connected areas, and calculating the path for each power-off line to restore power; verifying all paths, adjusting the energy storage resources for the successfully verified paths to add them to the queue to be executed, and regenerating the paths for the failed verification paths based on the regional topology and the overload margin of the target line by relying on adjustable distributed resources; executing resource allocation according to the path, and adjusting the low-voltage bus failure according to the real-time operating status. The full stop and full transfer process for low-voltage bus failures ensures the accuracy and efficiency of power restoration of the line after the failure through intelligent path calculation and verification, combined with energy storage and distributed resource adjustment.

[0012] As a preferred embodiment, the full stop and full transfer process specifically includes: isolating the faulty busbar includes: isolating all lines under the busbar from the busbar, and transferring the load under the line through the lines; calculating the path includes: calculating the available capacity of the power supply, and prioritizing the paths according to whether they are in the same plant and station and the number of controllable operation switches, combined with the degree of load balancing, etc. The full stop and full transfer process efficiently isolates the faulty busbar, ensures rapid load transfer and power supply restoration by accurately calculating and sorting the power supply restoration path, and improves the level of intelligence in responding to power grid faults.

[0013] Preferably, the adjustment of the adjustable distributed resources includes: relying on the equipment topology subordinate relationship of the distributed resources, aggregating the controllable distributed resources of the substation and the line, and analyzing their adjustable capacity; forming an adjustment control instruction according to the overload of the main transformer and the adjustable capacity, remotely adjusting and issuing the target distributed resource equipment, tracking and displaying the adjustment status, displaying the active power change of the target equipment and the execution status of the adjustment instruction, and alarming for abnormal adjustment operations. The intelligent adjustment of adjustable distributed resources ensures the accuracy and efficiency of resource adjustment through equipment topology analysis, capacity aggregation, instruction issuance and status tracking, and provides strong support for the stable operation of the power grid.

[0014] Preferably, the transfer process includes: based on topological transfer and flow calculation, for main transformers and lines exceeding the limit, by taking the feeder as the minimum transfer unit for cyclic calculation, giving priority to ensuring that the opposite main transformer / feeder is not overloaded, while pursuing the optimal transfer amount and controllable operation switch, and after obtaining the transfer plan, sorting and preferentially implementing it until the limit is completely transferred out or all feeders are circulated; after each plan is generated, the data section is updated according to the latest transfer plan. The transfer process is based on topological transfer and flow calculation, and through intelligent cyclic calculation and plan sorting, it ensures the safety and efficiency of the transfer process, realizes optimal resource allocation, and improves the ability of the power grid to cope with faults.

[0015] Preferably, the transfer process also includes: for the generated transfer plan, adapting the one-key remote control command issuing function, the setting includes dual login of the operating user and the operating guardian, and the account information is inconsistent; verifying the selected line operation mode adjustment plan, including checking the operation mode and operation information. If the verification passes, the remote control command is issued to the target device in a sequential control mode to update the real-time status. If the verification fails, the executed operation is restored. The transfer process uses the one-key remote control command issuing function to achieve dual login security verification, ensure the accurate execution of the transfer plan, restore the faulty equipment in time, and improve the automation and safety of power grid fault response.

[0016] The beneficial effects of the present invention are: 1. A station-level fault handling method of the present invention can accurately identify and respond to main transformer N-1 faults and low-voltage bus faults through intelligent monitoring and adjustment strategies, realize rapid power supply restoration after faults, and improve the stability and reliability of the power grid. 2. A station-level fault handling method of the present invention, with the help of advanced distributed resource regulation, power transfer plan calculation and one-key remote control command issuance functions, can optimize resource allocation, improve the automation and intelligence level of fault response, reduce the impact of faults on power grid operation, and improve operation and maintenance efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1The present invention discloses a flow chart of a substation main transformer N-1 fault processing method according to a station-level fault processing method.

[0018] Figure 2 The present invention discloses a low-voltage bus fault processing flow chart of a station-level fault processing method.

[0019] Figure 3 It is a full stop and full rotation flow chart of a station-level fault handling method of the present invention.

[0020] Figure 4 It is a schematic diagram of Example 2 of a station domain level fault handling method of the present invention. DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further specifically described below through embodiments and in conjunction with the accompanying drawings.

[0022] Embodiment 1: A site-level fault handling method of this embodiment is as follows: Figure 1 , Figure 2 and Figure 3 As shown in the figure, the one-key optimization processing function of substation faults monitors the faults of each substation in the jurisdiction in real time through the main transformer N-1 fault, low-voltage bus power outage fault and main transformer overload monitoring module. When the main transformer N-1 fault occurs and the load rate of the related main transformer exceeds the limit, the subsequent main transformer overload limit processing process is started. When the substation low-voltage bus fault occurs, the subsequent substation low-voltage bus fault processing process is started.

[0023] The processing flow for the overload of a single transformer caused by the N-1 fault of the main transformer is as follows: first, the adjustable distributed resource adjustment module is called to search for the adjustable substation-level distributed resources under the overloaded main transformer, and the distributed resource adjustment strategy is formed based on the specific information such as the current main transformer overload, the adjustable margin of distributed resources, etc., to reduce the target main transformer load rate. If the main transformer load rate is still over the limit after adjustment, the line one-key transfer module is called to search for the topological connection of the feeder under the main transformer, and the line one-key transfer plan is formed in combination with the current load conditions of the feeder / main transformer to further reduce the target main transformer load rate. If the load condition of the main transformer still does not meet the requirements, the line gap response (module) function is called to adjust the line load to meet the target main transformer load reduction requirements.

[0024] like Figure 1As shown in the figure, this flowchart describes the processing flow when the main transformer N-1 fails and the main transformer is overloaded. The process starts at the "main transformer N-1 failure and main transformer overload monitoring" link. The system monitors the status of the entire network equipment. Once the main transformer N-1 fails or the main transformer is overloaded, it will enter the processing stage. In the processing stage, the adjustable distributed resources are first searched and aggregated, and the adjustable capacity of these resources is analyzed. Then, based on the analysis of the transfer amount and adjustable resources, a series of adjustment control instructions are formed. These instructions are sent to the target distributed resource equipment through remote control to execute the corresponding resource adjustment. During the adjustment process, the system will track and display the adjustment status, including the active power changes of the target equipment and the execution status of the adjustment instructions. If an abnormal adjustment operation is found, the system will alarm.

[0025] After resource adjustment, if the main transformer is still overloaded, the system will enter the transfer stage. The transfer process is based on topological transfer and flow calculation, and the feeder is used as the minimum transfer unit for cyclic calculation. The system will give priority to ensuring that the main transformer / feeder on the opposite side is not overloaded, while pursuing the optimal transfer amount and controllable operation of the switch. After obtaining the transfer plan, the system will sort and implement it preferentially until the over-limit is completely transferred out or all feeders are cycled. After each transfer plan is generated, the system will update the data section according to the latest transfer plan. In general, this flowchart describes a complete processing process for main transformer N-1 faults and main transformer overloads, including monitoring, resource adjustment, and transfer, etc., to ensure the stable operation of the power grid and the rapid recovery of faults.

[0026] Low-voltage bus fault processing flow: First, call the line full stop and full transfer module to analyze the topological connection of the feeder under the main transformer, and form a full stop and full transfer plan in combination with the current load of the feeder. When verifying the plan, determine whether all lines can be transferred. If they can be fully transferred, directly execute the plan. If the transfer will cause some lines to overload, enable the adjustable distributed resource adjustment module, search for line-level distributed resources such as energy storage and adjustable load under the line, and perform resource adjustment according to the principle of moving energy storage first and then moving load, and finally achieve full stop and full transfer when the low-voltage bus fails.

[0027] like Figure 2As shown in the figure, the processing flow for the busbar fault, that is, the processing flow chart for the large-scale power outage fault of the substation, starts with "substation large-scale power outage fault monitoring", which is a warning and monitoring stage, used to monitor the operating status of the substation in real time. Once a large-scale power outage fault is found, the processing flow will be immediately entered. Entering the "full equipment status monitoring" stage, this is a comprehensive inspection and evaluation of the status of all equipment in the substation after the fault occurs to determine the specific location and cause of the fault. If it is confirmed that the fault involves the "substation low-voltage busbar", the "substation low-voltage busbar fault handling" process will be triggered. At this stage, the measures that may need to be taken include "line operation adjustment", that is, adjusting the operation mode of the line according to the fault situation; "distributed and adjustable distribution", which may refer to the use of distributed power sources or energy storage equipment to balance and adjust the supply and demand of the power system; "line crossing port", which may be a professional term, refers to crossing or bypassing the fault point through specific operations or equipment to ensure the normal supply of electricity.

[0028] The monitoring process for substation failures and main transformer overload is as follows: Among them, monitor the equipment operation information in the area under jurisdiction, comprehensively monitor and judge the main transformer active power, bus voltage, standby automatic operation, switch operation and other information, and judge whether the main transformer N-1 or low-voltage bus failure occurs. If the main transformer N-1 failure occurs, check whether the current main transformers are overloaded. If overloaded, start the subsequent main transformer overload limit processing process. If a large-scale power outage occurs in the substation, check the corresponding substation bus pressure loss. For the pressure loss, call the full stop and full transfer module, combine the accident emergency plan, start the substation low-voltage bus fault processing process to adjust the line operation.

[0029] The main transformer load factor is calculated as follows: read the transformer table 416 powertransformer, obtain the transformer winding table 417 transformerwinding information through the association relationship, filter out the low-voltage windings of the target monitoring voltage level, and calculate the current load factor according to "current value i / rated current amprating". According to the corresponding high-voltage winding, calculate the power load factor according to "active value p / winding normal rated power mvanom".

[0030] The main transformer load status monitoring function is designed as an independent sub-module, which is resident in the DSCADA host in the corresponding monitoring area, and monitors and updates the main transformer load information in real time and writes it into a specific table.

[0031] The process of adjusting adjustable distributed resources is as follows: relying on the equipment topology affiliation of distributed resources, the controllable distributed resources such as energy storage and converter stations at the substation and line levels are aggregated, and their adjustable capacity information such as adjustable margin, response speed, and active power characteristic curve are analyzed.

[0032] According to the regulation target (main transformer overload) and adjustable capacity, the regulation control command is generated to remotely regulate the target distributed resource equipment, track and display the regulation status, display the active power changes of related equipment and the execution status of the regulation command, and alarm for abnormal regulation operations.

[0033] For the power transfer process applied to both the main transformer N-1 fault and the low-voltage bus fault, this embodiment provides a one-key power transfer, and the process is as follows: mainly relying on the topology power transfer and power flow calculation service, for the specific over-limit of the main transformer and the line, the equipment under it is cyclically calculated, and integrated to form an overall power flow over-limit control solution combination. The specific logic is as follows: Taking the feeder as the smallest transfer unit, a feeder transfer scheme set is formed under the current data section, and the relevant schemes are sorted according to the priority of no overload of the opposite main transformer / feeder-optimal transfer quantity-controllable operation switch, and the current single optimal feeder transfer scheme is selected as the operator adjustment strategy (this scheme must ensure that the opposite main transformer / feeder is not overloaded, otherwise the circulation process will be terminated in advance) until all over-limit quantities are transferred out or all feeders under the main transformer are circulated. Among them, each time the operator adjustment strategy is formed, the current data section is updated according to the operation content of the latest selected transfer scheme, and subsequent strategy generation is calculated and analyzed in the latest data section.

[0034] For the generated transport adjustment strategy, a one-key remote control command issuing function is provided: Supports the security remote control function of dual login of the operating user and the operating guardian. The two types of login account information must remain inconsistent. If all logins are not successful as required, subsequent operation functions will be prohibited; Supports the verification function for the selected line operation mode adjustment plan, including verification of multiple types of information such as operation mode, operation safety, diagram change, and controllability of operation switches. If the verification fails, the corresponding failure reason will be returned to the substation main transformer N-1 fault one-key optimization processing function interface and subsequent remote control operations will be prohibited; Supports the execution / recovery function for the verified operation schemes. It sends the corresponding remote control instructions to the operation devices in accordance with the specific contents of the selected operation scheme in a sequential control manner, updates the remote control status in real time, and allows subsequent operations to be interrupted in case of failure. At the same time, the operation timeout limit, number of attempts and mode can be manually configured; Supports the recovery function for the operations that have been attempted to be executed, generates a recovery operation sequence according to the order in which the operations are executed, and provides corresponding recovery operation functions.

[0035] For the full stop and full transfer process of the line: When a large-scale power outage occurs in a substation, the full transfer and full stop module is called. For the bus failure of the target substation, relying on the topology transfer and network reconstruction services, the controllable energy storage resources and the line gap response load adjustment function are integrated to form a bus failure recovery combination plan by integrating the calculation and analysis results. The specific logic is as follows: Generation of full stop and full transfer plan: For the faulty busbar, all lines under the busbar are isolated from the busbar, and the load under the line is transferred between lines: Topological analysis is performed with the de-energized busbar as the starting point to obtain all de-energized lines and the first operable distribution network switch downstream of the outgoing switch of the de-energized line, and the plan operation status of the switch is set to achieve safe isolation; first, the de-energized lines are divided into several connected areas according to the connected areas, and the recoverable power supply plan for each de-energized line is calculated separately; the power supply recovery plans of several lines in each connected area are combined and analyzed, the power supply capacity is calculated, and the plan priorities are sorted according to whether they are in the same plant or station, the number of controllable operating switches, the degree of load balancing, etc., to form an operation mode adjustment plan.

[0036] Plan verification: Verify the generated adjustment plan. If the verification passes, it will be included in the list of plans to be executed. Otherwise, it will be displayed as verification failure. The verification content includes remote signal quality code verification, power supply capacity verification (to determine whether the opposite side line is overloaded), operation mode verification (whether the switch status meets the requirements), and safety verification (whether the maintenance equipment will be energized after the power transfer).

[0037] Adjustment of adjustable energy storage resources: For lines where plan verification fails due to line overload, the line adjustable energy storage resources are recorded based on the topological affiliation of distributed resource equipment, and the adjustable capacity information such as adjustable margin and response speed is analyzed. Combined with the target line overload load margin, a record of the plan to be executed is formed, and the plan is verified. The plans that pass the verification are added to the list to be executed.

[0038] Line gap response load adjustment: If the line load situation still does not meet the requirements through controllable energy storage adjustment, it can also rely on the real-time operating status to further perform interruptible load control by calling the corresponding demand platform (demand response module to accurately cut load), and reduce the line load to meet the target line load reduction requirements. A record of the plan to be executed is formed, and the plan is verified. The plan that passes the verification is added to the list to be executed.

[0039] After the operation plan is generated, the remote control method of the successful verification line can be flexibly adjusted. The processing software provides three remote control methods: single-step execution, sequential execution, and concurrent execution. The dispatcher can choose the corresponding remote control mode according to the actual on-site control needs.

[0040] Implement dual login security for the operator and the guardian to ensure remote control. After clicking confirm, the system will perform remote control according to the operation list.

[0041] Send corresponding remote control commands to the operating device, update the remote control status in real time, and allow subsequent operations to be interrupted when failed. At the same time, the operation timeout limit, number of attempts and mode can be manually configured.

[0042] For adjustable energy storage equipment, the target distributed resource equipment is remotely adjusted and issued according to the formed adjustment control instructions, the adjustment status is tracked and displayed, the active power changes of related equipment and the execution status of the adjustment instructions are displayed, and an alarm is issued for abnormal adjustment operations.

[0043] like Figure 3 As shown in the figure, a process sent from a Quanke device to a demand response platform is detailed. First, the system monitors the status of the Quanke device to ensure its normal operation. Once a situation that requires response is found, the process enters the next step, which is the contact switch setting and power outage. These two steps may be to isolate the fault or adjust the power supply. The system will perform a series of analyses and calculations based on the current power situation. This includes evaluating the load that can compensate for overloads and short-circuit detection of the routes of distributed energy systems. At the same time, the system will also pay attention to the operating status of the lines under the bus, including whether the load is overloaded and whether there are risks to the bus or lines.

[0044] Based on these analyses, the system will generate corresponding treatment plans. These plans may involve adjustments to line loads, changes in bus or line operation modes, etc. After generating the plan, the system will verify the plan to ensure its feasibility and safety. If the verification passes, the system will execute the plan. Throughout the process, the system will continuously calculate the constant margin of the line load to grasp the operating status of the power system in real time. At the same time, the system will maintain close contact with the demand response platform and make corresponding adjustments according to the platform's needs. In the end, the system ensures the stable and safe operation of the power system through a series of precise operations and controls.

[0045] In this embodiment, the data interaction process also applied to the invention itself includes: (1) Input data: Distributed resource data: Energy storage data: Topological affiliation of energy storage devices; Measured data of energy storage equipment: active power, reactive power, voltage, current; Energy storage margin information of energy storage equipment; Energy storage device status and historical information.

[0046] Flexible DC device data: Topological dependencies of flexible DC devices; Measured data of flexible DC device: active power, reactive power, voltage and current; Flexible DC device regulation margin information; Flexible DC device status and history information.

[0047] Intrinsic distribution network equipment information and measurement data: Serial number Mainnet equipment Static model data Real-time measurement data 1 transformer Device Affiliation Active power, reactive power, current, voltage 2 breaker Device Affiliation Active power, reactive power, current, voltage, remote signaling 3 load Device Affiliation Active power, reactive power, current, voltage 4 Distribution switch Device Affiliation Active power, reactive power, current, voltage, remote signaling (2) Output data Main transformer load monitoring information: power flow, load rate; One-key optimization processing strategy for substation main transformer N-1 fault; One-click optimization and handling strategy for substation low-voltage busbar faults.

[0048] Embodiment 2: A site-level fault handling method of this embodiment is as follows: Figure 4 As shown in FIG. 1 , this embodiment depicts a power system configuration named Jianshan Substation, which includes three main transformers (#1, #2, #3) and 34 lines (21 20kV lines and 13 10kV lines) under its jurisdiction. Figure 4 The following description is made in conjunction with the methods and processes mentioned in Example 1.

[0049] Jianshan Substation has three main transformers, namely #1 main transformer (50MVA), #2 main transformer (80MVA) and #3 main transformer (80MVA). These main transformers are responsible for providing power to the 21 20kV lines and 13 10kV lines under its jurisdiction.

[0050] Its available resources include: main transformer-level adjustable resources and line-level adjustable resources. The main transformer level includes energy storage facilities and Phoenix Converter Station located on Xianxia Road. These resources can provide additional power support or regulation at the main transformer level. The second line level includes four specific lines equipped with user-level energy storage facilities, namely the Hejin Electronic Energy Storage on the North Shore Line, the Core Energy Microgrid Energy Storage on the Anjiang Line, the Haiding Mechanical Energy Storage on the Tingchao Line, and the Jiatong Expressway Energy Storage on the Huangshan Line. These energy storage facilities can provide power support or regulation at the line level.

[0051] The scenario implementation logic includes: For the main transformer N-1 fault, when the #2 main transformer has an N-1 fault, the main transformer standby automatic transfer system will automatically transfer the load of the #2 main transformer to the #3 main transformer. This may cause the load rate of the #3 main transformer to exceed its limit. The substation fault and main transformer overload monitoring module will immediately detect this situation and start the main transformer overload limit handling process. First, the flexible direct current converter station (Phoenix converter station) will be called to transfer part of the load of the #3 main transformer to the #1 main transformer to reduce the load rate of the #3 main transformer. If the load rate still exceeds the limit, the Xianxia Road energy storage will be called to support the load rate adjustment demand by discharging. If the load rate still exceeds the limit after adjustment, the system will enable the line one-key transfer function to quickly transfer part of the line under the #3 main transformer to other substations. If the above measures still cannot meet the requirements, the line gap will be forwarded to the demand response platform, and the line adjustable load will be called for voltage drop processing.

[0052] For low-voltage bus failure, when a low-voltage bus failure occurs in the #2 main transformer, the substation fault monitoring module will detect a large-scale power outage and start the low-voltage bus fault handling process. First, the system will call the line full stop and full transfer module to generate a full stop and full transfer plan to transfer all low-voltage lines of the #3 main transformer to the opposite substation. Then, the system will verify the plan to determine whether all lines can be successfully transferred. If all can be transferred, the plan will be executed directly. If the transfer will cause some lines to overload, the system will enable the adjustable distributed resource regulation module. First, the user energy storage of the line is called for discharge. If it still does not meet the requirements, the line load is subjected to voltage drop processing, and finally the full stop and full transfer when the low-voltage bus fails is achieved.

[0053] It should be understood that the embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope limited by the appended claims of the application.

Claims

1. A site-level fault handling method, characterized in that: The specific steps include: S1: Monitor the main transformer load and bus voltage operation within the jurisdiction, identify the main transformer N-1 fault and low-voltage bus fault classification; S2: When the main transformer N-1 fails, the resources are adjusted based on the main transformer dispatch information to reduce the target main transformer load rate. When the load rate exceeds the limit, the power transfer and line gap control are carried out step by step. S3: In the event of a low-voltage busbar fault, a full-stop and full-restart process is formulated in combination with the topological structure of the feeder provided by the main transformer, and the power supply and resource adjustment methods are adopted step by step according to the severity of the fault.

2. A site-level fault handling method according to claim 1, characterized in that: In S1: the main transformer load and bus voltage operating data in the area under comprehensive monitoring are calculated to determine the main transformer overload situation. If the number of overloaded main transformers is not less than 1, it is determined that the main transformer N-1 fault has occurred. If the number of substations with power outages within the scope of the main transformer is greater than n, the corresponding substation bus voltage loss situation is checked to determine the low-voltage bus fault. An independent module for main transformer load status monitoring is set.

3. A station-level fault handling method according to claim 2, characterized in that: The main transformer load factor is calculated as follows: read the transformer table, obtain the transformer winding table information through the association relationship, filter out the low-voltage windings of the target monitoring voltage level, and calculate the current load factor according to "current value i / rated current"; according to the corresponding high-voltage winding, calculate the power load factor according to "active value p / normal rated power of winding".

4. A site-level fault handling method according to claim 1, characterized in that: The fault of main transformer N-1 causes the overload of a single transformer to exceed the limit. The overload is handled in stages: S2.1: Basic regulation: Search for substation-level adjustable distributed resources under overloaded main transformers, and reduce the target main transformer load rate by comprehensively considering the current main transformer overload and the adjustable margin of distributed resources; S2.2: Level I regulation: After basic regulation, if the load rate of the main transformer is still over the limit, the line is called for supply transfer, the topological connection of the feeder under the main transformer is searched, and the supply transfer adjustment is combined with the current load of the feeder / main transformer; S2.3: Level II regulation: Obtain the line gap response of the feeder provided by the main transformer and adjust the line load to reduce the load of the main transformer.

5. A site-level fault handling method according to claim 1, characterized in that: Low voltage bus fault step-by-step adjustment: S3.1: Basic regulation: Analyze the topological structure of the feeder under the main transformer, formulate and verify the full stop and full transfer process based on the current load of the feeder, and determine whether all lines can be transferred. If they can be fully transferred, directly implement the plan; S3.2: Advanced regulation: If the transfer causes some lines to be overloaded, the adjustable distributed resource regulation is adopted to search for line-level distributed resources such as energy storage and adjustable load under the current target line, and the resource regulation is performed in the order of energy storage regulation and load regulation.

6. A site-level fault handling method according to claim 5, characterized in that: For low-voltage bus failures in target substations, the full stop and full transfer process includes: Isolate the faulty busbar, obtain all power-lost lines, divide the connected areas, and calculate the path for restoring power to each power-lost line; Verify all paths. For paths that have successfully been verified, adjust the energy storage resources and add them to the queue to be executed. For paths that have failed to be verified, use the adjustable distributed resources to regenerate the paths according to the regional topology and the target line overload margin. Resource allocation is performed according to the path, and low-voltage bus faults are adjusted according to the real-time operating status.

7. A site-level fault handling method according to claim 6, characterized in that: The full stop and full transfer process also includes: Isolating the faulty bus includes: isolating all the lines under the bus from the bus, and transferring the load under the line through the lines; calculating the path includes: calculating the available capacity of the power supply, and prioritizing the paths according to whether they are in the same plant and station and the number of controllable operating switches, combined with the degree of load balancing.

8. A station-level fault handling method according to claim 4, 5 or 6, characterized in that: Adjustments to adjustable distributed resources include: Relying on the equipment topology subordinate relationship of distributed resources, the controllable distributed resources of substations and lines are aggregated and their adjustable capacity is analyzed; according to the overload and adjustable capacity of the main transformer, the regulation control instructions are formed, and the target distributed resource equipment is remotely adjusted and issued, the regulation status is tracked and displayed, the active power changes of the target equipment and the execution status of the regulation instructions are displayed, and alarms are issued for abnormal regulation operations.

9. A station-level fault handling method according to claim 1, 4 or 5, characterized in that: The transfer process includes: Based on topological transfer and flow calculation, for main transformer and line over-limit, cyclic calculation is performed with feeder as the minimum transfer unit, giving priority to ensuring that the opposite main transformer / feeder is not overloaded, while pursuing optimal transfer and controllable operation of switches. After the transfer plans are obtained, they are sorted and implemented preferentially until the over-limit is completely transferred out or all feeders are cycled; after each plan is generated, the data section is updated according to the latest transfer plan.

10. A site-level fault handling method according to claim 9, characterized in that: The transfer process also includes: For the generated power transfer plan, a one-key remote control command issuing function is adapted, and its settings include dual login of the operating user and the operating supervisor, and the account information is inconsistent; the operation mode adjustment plan of the selected line is verified, including the inspection of the operation mode and operation information. If the verification passes, the remote control command is issued to the target device in a sequential control manner to update the real-time status. If the verification fails, the executed operations are restored.

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