Ring main unit line ledger sorting method based on ground capacitance current
By analyzing ground capacitance current and applying Kirchhoff's current law, the ground capacitance current of the ring main unit lines is monitored in real time, and the records are automatically sorted out. This solves the problem of misjudgment of faults caused by the complex topology of the ring main unit, and improves the accuracy of fault assessment and the level of power grid management.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2026-04-03
AI Technical Summary
The multi-input and multi-output wiring method of traditional ring main units leads to a complex power grid topology. Existing fault monitoring and diagnosis systems have low accuracy, manual record management is inefficient and prone to errors, increases the burden on operation and maintenance personnel, and affects power supply reliability and intelligent management level.
By analyzing the ground capacitance current and combining it with Kirchhoff's current law, the ground capacitance current values of each incoming and outgoing line of the ring main unit are monitored and calculated in real time. The line ledger is automatically sorted out, and changes in topology are identified and calibrated.
It improves the accuracy and efficiency of fault diagnosis, reduces operation and maintenance costs, enhances power supply reliability, and promotes the in-depth application of distribution automation systems and the intelligentization of power grid management.
Smart Images
Figure CN121790933A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of power technology and relates to a method for sorting out the ledgers of switchgear for cable lines in the power industry, such as switching stations, ring main units, switching stations, and step-up substations. In particular, it relates to a method for sorting out the ledgers of ring main units based on the ground capacitance current. Background Technology
[0002] As power systems continue to evolve and grid reliability standards continue to improve, ring main units (RMMs), as key nodes in urban distribution networks, are facing increasingly complex design and operation strategies. Traditional RMM configurations widely employ flexible multi-input, multi-output wiring patterns to enhance the redundancy and scalability of regional power supply, deploying multiple backup lines to anticipate future increases in power demand and facilitate rapid recovery from sudden faults. However, while this highly flexible wiring method improves grid resilience, it also presents more stringent challenges to fault monitoring and diagnosis systems.
[0003] In particular, the widely used Distribution Terminal Units (DTUs) are encountering unprecedented challenges when performing fault location and assessment tasks. Frequent changes in grid operating conditions, including but not limited to dynamic load transfers, timely commissioning of backup lines, role changes of existing lines (such as switching from primary to backup), loop closing operations, and flexible switching of tie switches, can all lead to drastic changes in the grid topology, resulting in a series of technical difficulties. Specifically, this manifests as increased inconsistencies in transformer polarity configurations, and a more complex relationship between line detection parameters and actual operating conditions. The direct consequence is a significant decrease in the accuracy of fault assessment, even leading to misjudgments, greatly increasing the workload of maintenance personnel and posing a potential threat to the continuity and reliability of power supply.
[0004] Faced with this technological bottleneck, the traditional reliance on manual recording and management is increasingly proving inadequate. Manual recording is not only inefficient but also highly susceptible to loss of valuable information due to personnel turnover, incomplete records, or the passage of time. This makes it difficult to quickly and accurately pinpoint the root cause of problems when they occur, prolonging troubleshooting and repair time and further exacerbating the decline in power supply reliability. Furthermore, the inefficiency of this management method limits the in-depth application of distribution automation systems in fault diagnosis, maintenance scheduling, and other areas, hindering the effective improvement of the intelligent management level of the distribution network.
[0005] Therefore, it is particularly important to develop a new method that can effectively address topology anomalies in ring main units and achieve accurate fault diagnosis. Summary of the Invention
[0006] To address the problems existing in the prior art, this invention provides a method for organizing the ring main unit (RNB) line ledger based on ground capacitance current analysis. This method aims to accurately capture the dynamic changes in the power grid topology through scientific data acquisition and analysis, combined with real-time monitoring of the key electrical parameter, ground capacitance current, to achieve intelligent organization and dynamic updating of the RNB line ledger. This not only helps improve the accuracy and efficiency of fault diagnosis and reduce the workload of maintenance personnel, but also provides solid data support for the in-depth application of distribution automation systems, propelling the level of intelligent power grid management to a new height.
[0007] To achieve the above objectives, the present invention provides the following technical solution:
[0008] A method for organizing the line ledger of ring main unit based on ground capacitance current, the steps of which are as follows:
[0009] S1: Collect three-phase current data in each ring main unit of the cable line, and use the terminal to analyze and identify the opening and closing information;
[0010] S2: Based on the tripping information, collect the three-phase current data of each ring main unit in the cable line before tripping;
[0011] S3: Based on the closing information, collect the three-phase current data of each ring main unit in the cable line after closing;
[0012] S4: Based on the information collected by the equipment, determine the incoming and outgoing lines of the ring main unit, including information on the backup lines, and establish a ledger;
[0013] S5: Based on the three-phase current data of each ring main unit in the cable line collected before the circuit breaker is tripped, determine the ground capacitance current value of each incoming and outgoing line.
[0014] S6: Based on the three-phase current data of each ring main unit in the cable line after the switch is closed, analyze the ground capacitance current value of each incoming and outgoing line, and calculate the sum of the ground capacitance current values of all incoming and outgoing lines under the ring main unit.
[0015] S7: Output all node information that meets the requirements of the ring network counter ledger anomaly and recalibrate the ledger, continuing steps S1 to S6.
[0016] Furthermore, the method for determining the tripping information in step S2 is as follows: if there is a sudden change in the three-phase current of one incoming and one outgoing line under the ring main unit that is greater than α and the effective value is less than β, the line is tripped, where α represents the effective value of the sinusoidal power frequency of the next cycle minus the effective value of the sinusoidal power frequency of the previous cycle, and β represents the effective value of a single sinusoidal power frequency.
[0017] Furthermore, the method for determining the closing information in step S3 is as follows: if there is a sudden change in the three-phase current of one incoming and one outgoing line under the ring network cabinet that is greater than γ, and the initial three-phase current value is less than δ, then the line is closed. Here, γ represents the effective value of the sinusoidal power frequency of the next cycle minus the effective value of the sinusoidal power frequency of the previous cycle, and δ represents the effective value of a single sinusoidal power frequency.
[0018] Furthermore, in step S5, if there is no closing information and at least one incoming line and one outgoing line have no ground capacitance current value, then the ring main unit is considered to have an abnormal ledger.
[0019] Furthermore, in step S6, the difference between the sum of the obtained line-to-ground capacitance current values and the sum of the corresponding line-to-ground capacitance current values is calculated. When this difference meets a preset threshold, the ring main unit is considered to have an abnormal ledger.
[0020] Furthermore, the preset threshold for the difference in step S6 is set to 2A.
[0021] Furthermore, the ledger information output in step S7 includes the ring main unit name, the time of opening and closing, the names of each incoming and outgoing line of the ring main unit, and the information name of the standby line, including the polarity of the transformers for incoming line to outgoing line, outgoing line to incoming line, standby line commissioning, and the conversion of used lines to standby.
[0022] Furthermore, the method for calculating the ground capacitance current value is as follows: based on the sampled values of the three-phase phase currents, taking the A-phase current as the standard, the reactive current value is calculated using the Fourier transform method, which is the ground capacitance current value of that phase.
[0023] Furthermore, the method for identifying abnormal ledger entries is as follows: According to Kirchhoff's current law, the relative ground capacitance current value of all incoming lines is equal to the relative ground capacitance current value of all outgoing lines. If they are not equal, then the ledger entries of the ring main unit are abnormal. The ledger information is then re-examined based on the line load transfer, the commissioning of standby lines, the conversion of used lines to standby, the closing of loops, and the commissioning of tie switches.
[0024] Furthermore, the method for reorganizing the ledger is as follows: based on Kirchhoff's current law, according to the principle that the relative ground capacitance current value of all incoming lines is equal to the relative ground capacitance current value of all outgoing lines, whether there is a ground capacitance value, and information before the circuit breaker is opened or closed, the incoming and outgoing lines are adjusted, and the ledger information is reorganized according to the line load transfer, the commissioning of standby lines, the conversion of used lines to standby, the closing of loops, and the commissioning of tie switches.
[0025] The beneficial effects of this invention are:
[0026] The ring main unit line ledger sorting method based on ground capacitance current provided by this invention utilizes the topological Kirchhoff current law relationship to detect abnormal relationships in the line ledger caused by line load transfer, standby line commissioning, used line transfer to standby, loop closing and tie switch commissioning, etc., so as to better sort out the ledger and conduct fault analysis. The judgment method of this application embodiment is simple and has high practicality.
[0027] Compared with existing technologies, the ring main unit line ledger sorting method based on ground capacitance current described in this invention has the following technical features and beneficial effects:
[0028] (1) Improve the accuracy of fault assessment: By real-time monitoring and calculation of the ground capacitance current values of each incoming and outgoing line of the ring network cabinet, the present invention can accurately identify changes in the power grid topology, effectively avoid the problem of chaotic line detection correspondence caused by complex operations such as load transfer and standby line commissioning, thereby significantly improving the accuracy and reliability of fault assessment.
[0029] (2) Reduced operation and maintenance costs and workload: Automated and intelligent ledger sorting methods replace traditional manual recording and management methods, reducing data loss and errors caused by human factors, reducing the workload of operation and maintenance personnel, and improving work efficiency. At the same time, timely ledger updates and anomaly detection can reduce power outage time caused by untimely fault diagnosis, further reducing operation and maintenance costs.
[0030] (3) Enhanced power supply reliability: This invention ensures the accuracy of the power grid topology by continuously monitoring and calibrating the ring main unit line ledger, providing strong support for quickly locating and resolving power grid faults. When a power grid fault occurs, the fault point can be quickly identified and corresponding measures can be taken to reduce the scope and duration of power outages and improve power supply reliability.
[0031] (4) Promoting the development of distribution automation: The implementation of this invention provides a solid data foundation for the in-depth application of distribution automation systems. Through accurate and real-time line ledger information, distribution automation systems can more efficiently perform functions such as fault analysis, load forecasting, and optimized scheduling, thus promoting the development of distribution networks towards intelligence and automation.
[0032] (5) Improve power grid management efficiency: The method of this invention is not only applicable to the sorting and management of ring main unit line ledgers, but can also be extended to the topology management and maintenance of the entire distribution network. Through standardized data processing and anomaly detection processes, the efficiency and standardization of power grid management are achieved, thereby improving the overall management level.
[0033] In summary, the ring main unit line ledger sorting method based on ground capacitance current of the present invention has shown significant beneficial effects in improving the accuracy of fault diagnosis, reducing operation and maintenance costs and workload, enhancing power supply reliability, promoting the development of distribution automation, and improving power grid management efficiency. Attached Figure Description
[0034] To more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:
[0035] Figure 1 This is a schematic diagram of the method for sorting out the line ledger of ring main unit based on ground capacitance current according to the present invention.
[0036] Figure 2 This is a schematic diagram illustrating the logic of the ring main unit line ledger sorting based on the ground capacitance current of the present invention.
[0037] Figure 3 This is a schematic diagram of the basic structure of the ring main unit circuit of the present invention;
[0038] Figure 4 This is a schematic diagram of Kirchhoff's current law for the capacitance current to ground of the ring main unit line in this invention. Detailed Implementation
[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The following description, in conjunction with the accompanying drawings... Figure 1-4 The method for sorting out the ring main unit line ledger based on the ground capacitance current is further explained.
[0040] Example 1
[0041] To address the shortcomings of existing technologies, the present invention aims to provide a method for sorting out the ledger of ring main unit lines based on ground capacitance current, which can better solve the problem of misjudgment of faults caused by changes in the ledger.
[0042] The objective of this invention is achieved through the following technical solution:
[0043] A method for organizing the line ledger of ring main unit based on ground capacitance current includes the following steps:
[0044] S1: Collect three-phase current data in each ring main unit of the cable line, and use the terminal to analyze and identify the opening and closing information;
[0045] S2: Based on the tripping information, collect the three-phase current data of each ring main unit in the cable line before tripping;
[0046] S3: Based on the closing information, collect the three-phase current data of each ring main unit in the cable line after closing;
[0047] S4: Based on the information collected by the equipment, determine the incoming and outgoing lines of the ring main unit, including information on the backup lines, and establish a ledger;
[0048] S5: Based on the three-phase current data of each ring main unit in the cable line collected before the circuit breaker is tripped, determine the ground capacitance current value of each incoming and outgoing line.
[0049] If there is no closing information and at least one incoming and outgoing line has no ground capacitance current value, the ring main unit is considered to have an abnormal ledger.
[0050] S6: Based on the three-phase current data of each ring main unit in the cable line after the switch is closed, analyze the ground capacitance current value of each incoming and outgoing line, and calculate the sum of the ground capacitance current values of all incoming and outgoing lines under the ring main unit.
[0051] The difference between the sum of the line-to-ground capacitance current values and the sum of the corresponding line-to-ground capacitance current values is calculated. When this difference meets a preset threshold, the ring main unit is considered to have an abnormal ledger.
[0052] S7: Output all node information that meets the requirements of the ring network counter ledger anomaly and recalibrate the ledger, continuing steps S1 to S6.
[0053] Preferably, the method for determining the tripping information in step 2 is as follows: if there is a sudden change in the three-phase current of one incoming and one outgoing line under the ring main unit that is greater than 1A (the effective value of the sinusoidal power frequency of the next cycle minus the effective value of the sinusoidal power frequency of the previous cycle) and the effective value is less than 0.2A (the effective value of a single sinusoidal power frequency), the line is tripped.
[0054] Preferably, the method for determining the closing information in step 3 is as follows: if there is a sudden change in the three-phase current of one incoming and outgoing line under the ring main unit that is greater than 100A (the effective value of the sinusoidal power frequency of the next cycle minus the effective value of the sinusoidal power frequency of the previous cycle) and the initial three-phase current value is less than 0.2A (the effective value of a single sinusoidal power frequency), the line is closed.
[0055] Preferably, the preset threshold for the difference in step 6 is set to 2A.
[0056] Preferably, the ledger information output in step 7 should include the name of the ring main unit, the time of opening and closing, the names of each incoming and outgoing line of the ring main unit, the information name of the standby line, including the polarity of the transformers for incoming line to outgoing line, outgoing line to incoming line, standby line commissioning, and the conversion of used lines to standby.
[0057] Preferably, the method for calculating the ground capacitance current value is as follows: based on the sampled values of the three-phase phase currents, taking the A-phase current as the standard, the reactive current value is calculated by the Fourier transform method, which is the ground capacitance current value of that phase.
[0058] Preferably, the method for identifying abnormal ledger entries is as follows: According to Kirchhoff's current law, the relative ground capacitance current value of all incoming lines is equal to the relative ground capacitance current value of all outgoing lines. If they are not equal, then the ledger entries of the ring main unit are abnormal. The ledger information is then re-sorted based on the line load transfer, the commissioning of standby lines, the conversion of used lines to standby, the closing of loops, and the commissioning of tie switches.
[0059] Preferably, the method for reorganizing the ledger is as follows: based on Kirchhoff's current law, according to the principle that the relative ground capacitance current value of all incoming lines is equal to the relative ground capacitance current value of all outgoing lines, whether there is a ground capacitance value, and information before the circuit breaker is opened or closed, the incoming and outgoing lines are adjusted, and the ledger information is reorganized according to the line load transfer, the commissioning of standby lines, the conversion of used lines to standby, the closing of loops, and the commissioning of tie switches.
[0060] Example 2
[0061] This embodiment is either a new embodiment or a supplement to Embodiment 1.
[0062] Combined with appendix Figure 1 and appendix Figure 2 A method for organizing the line ledger of ring main unit based on ground capacitance current, which includes the following steps:
[0063] S1: Collect three-phase current data in each ring main unit of the cable line, and use the terminal to analyze and identify the opening and closing information;
[0064] S2: Based on the tripping information, collect the three-phase current data of each ring main unit in the cable line before tripping;
[0065] S3: Based on the closing information, collect the three-phase current data of each ring main unit in the cable line after closing;
[0066] S4: Based on the information collected by the equipment, determine the incoming and outgoing lines of the ring main unit, including information on the backup lines, and establish a ledger;
[0067] S5: Based on the three-phase current data of each ring main unit in the cable line collected before the circuit breaker is tripped, determine the ground capacitance current value of each incoming and outgoing line.
[0068] If there is no closing information and at least one incoming and outgoing line has no ground capacitance current value, the ring main unit is considered to have an abnormal ledger.
[0069] S6: Based on the three-phase current data of each ring main unit in the cable line after the switch is closed, analyze the ground capacitance current value of each incoming and outgoing line, and calculate the sum of the ground capacitance current values of all incoming and outgoing lines under the ring main unit.
[0070] The difference between the sum of the line-to-ground capacitance current values and the sum of the corresponding line-to-ground capacitance current values is calculated. When this difference meets a preset threshold, the ring main unit is considered to have an abnormal ledger.
[0071] S7: Output all node information that meets the requirements of the ring network counter ledger anomaly and recalibrate the ledger, continuing steps S1 to S6.
[0072] Preferably, the method for determining the tripping information in step 2 is as follows: if there is a sudden change in the three-phase current of one incoming and one outgoing line under the ring main unit that is greater than 1A and the effective value is less than 0.2A, the line is tripped.
[0073] Preferably, the method for determining the closing information in step 3 is as follows: if there is a sudden change in the three-phase current of one incoming and one outgoing line under the ring main unit that is greater than 100A and the initial three-phase current value is less than 0.2A, the line is closed.
[0074] Preferably, the preset threshold for the difference in step 6 is set to 2A.
[0075] Preferably, the ledger information output in step 7 should include the name of the ring main unit, the time of opening and closing, the names of each incoming and outgoing line of the ring main unit, the information name of the standby line, including the polarity of the transformers for incoming line to outgoing line, outgoing line to incoming line, standby line commissioning, and the conversion of used lines to standby.
[0076] Preferably, the method for calculating the ground capacitance current value is as follows: based on the sampled values of the three-phase phase currents, taking the A-phase current as the standard, the reactive current value is calculated by the Fourier transform method, which is the ground capacitance current value of that phase.
[0077] Preferably, the method for identifying abnormal ledger entries is as follows: According to Kirchhoff's current law, the relative ground capacitance current value of all incoming lines is equal to the relative ground capacitance current value of all outgoing lines. If they are not equal, then the ledger entries of the ring main unit are abnormal. The ledger information is then re-sorted based on the line load transfer, the commissioning of standby lines, the conversion of used lines to standby, the closing of loops, and the commissioning of tie switches.
[0078] Preferably, the method for reorganizing the ledger is as follows: based on Kirchhoff's current law, according to the principle that the relative ground capacitance current value of all incoming lines is equal to the relative ground capacitance current value of all outgoing lines, whether there is a ground capacitance value, and information before the circuit breaker is opened or closed, the incoming and outgoing lines are adjusted, and the ledger information is reorganized according to the line load transfer, the commissioning of standby lines, the conversion of used lines to standby, the closing of loops, and the commissioning of tie switches.
[0079] For Example 2, the line topology diagram is as follows: Figure 3 As shown, there are a total of 6 topology nodes. Since the methods for judging topology anomalies are similar for each node, ... Figure 3 For example.
[0080] Based on the tripping information, data is collected to determine the effective data collection nodes in the topology. All nodes are traversed, and a sampling time for phase A is selected. The sum of the ground capacitance currents of all effective outgoing nodes under each node with an incoming line is calculated. For line 1, the sum of the ground capacitance currents of all effective outgoing nodes of lines 2, 3, 4, 5, and 6 is equal to the value of line 1, indicating that the incoming line node has no topological anomaly. If the ground capacitance current of incoming line 1 is equal to the sum of the ground capacitances of lines 2, 3, 4, and 5, then line 6 has been separated, and the topology is abnormal. If the ground capacitance current of line 6 is equal to the sum of the ground capacitances of lines 1, 2, 3, 4, and 5, then outgoing line 6 is an incoming line, and line 1's incoming line becomes an outgoing line, indicating a topological anomaly, and the ledger is modified. Similarly, Kirchhoff's current law is applied based on the line load transfer, standby line commissioning, used line conversion to standby, loop closing, and tie switch commissioning status to re-organize the ledger information.
[0081] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A method for organizing the line ledger of ring main unit based on ground capacitance current, characterized in that, The steps are as follows: S1: Collect three-phase current data in each ring main unit of the cable line, and use the terminal to analyze and identify the opening and closing information; S2: Based on the tripping information, collect the three-phase current data of each ring main unit in the cable line before tripping; S3: Based on the closing information, collect the three-phase current data of each ring main unit in the cable line after closing; S4: Based on the information collected by the equipment, determine the incoming and outgoing lines of the ring main unit, including information on the backup lines, and establish a ledger; S5: Based on the three-phase current data of each ring main unit in the cable line collected before the circuit breaker is tripped, determine the ground capacitance current value of each incoming and outgoing line. S6: Based on the three-phase current data of each ring main unit in the cable line after the switch is closed, analyze the ground capacitance current value of each incoming and outgoing line, and calculate the sum of the ground capacitance current values of all incoming and outgoing lines under the ring main unit. S7: Output all node information that meets the requirements of the ring network counter ledger anomaly and recalibrate the ledger, continuing steps S1 to S6.
2. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, The method for determining the tripping information in step S2 is as follows: if there is a sudden change in the three-phase current of one incoming and one outgoing line under the ring network cabinet that is greater than α and the effective value is less than β, the line is tripped. Here, α represents the effective value of the sinusoidal power frequency of the next cycle minus the effective value of the sinusoidal power frequency of the previous cycle, and β represents the effective value of a single sinusoidal power frequency.
3. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, The method for determining the closing information in step S3 is as follows: if there is a sudden change in the three-phase current of one incoming and one outgoing line under the ring network cabinet that is greater than γ, and the initial three-phase current value is less than δ, then the line is closed. Here, γ represents the effective value of the sinusoidal power frequency of the next cycle minus the effective value of the sinusoidal power frequency of the previous cycle, and δ represents the effective value of a single sinusoidal power frequency.
4. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, In step S5, if there is no closing information and at least one incoming line and one outgoing line have no ground capacitance current value, then the ring main unit is considered to have an abnormal ledger.
5. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, In step S6, the difference between the sum of the obtained line-to-ground capacitance current values and the sum of the corresponding line-to-ground capacitance current values is calculated. When this difference meets a preset threshold, the ring main unit is considered to have an abnormal ledger.
6. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, The preset threshold for the difference in step S6 is set to 2A.
7. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, The ledger information output in step S7 includes the ring main unit name, the time of opening and closing, the names of each incoming and outgoing line of the ring main unit, the information name of the standby line, including incoming line to outgoing line, outgoing line to incoming line, standby line commissioning, and the polarity of the current transformer for the used line to be converted to standby.
8. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, The method for calculating the ground capacitance current value is as follows: based on the sampled values of the three-phase phase currents, taking the A-phase current as the standard, the reactive current value is calculated using the Fourier transform method, which is the ground capacitance current value of that phase.
9. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, The method for identifying abnormal ledger entries is as follows: According to Kirchhoff's current law, the relative ground capacitance current value of all incoming lines is equal to the relative ground capacitance current value of all outgoing lines. If they are not equal, then the ledger entries of the ring main unit are abnormal. The ledger information is then re-examined based on the line load transfer, the commissioning of standby lines, the conversion of used lines to standby, the closing of loops, and the commissioning of tie switches.
10. The method for sorting out ring main unit line ledgers based on ground capacitance current as described in claim 1, characterized in that, The method for reorganizing the ledger is as follows: Based on Kirchhoff's current law, and according to the principle that the relative ground capacitance current value of all incoming lines is equal to the relative ground capacitance current value of all outgoing lines, the presence or absence of ground capacitance value, and information before opening or closing the switch, the incoming and outgoing lines are adjusted. The ledger information is reorganized based on the transfer of line load, commissioning of standby lines, conversion of used lines to standby, loop closing, and commissioning of tie switches.