Automatic feeder fault processing system based on 5G network

Abstract

The invention discloses an automatic feeder fault processing method based on a 5G network, and the method improves the fault processing capability of a power distribution network through the high speed, low delay and high safety of the 5G communication network, can quickly position a fault region through the information exchange between power distribution terminals in combination with the fault signals of the power distribution terminals and adjacent terminals, and improves the fault processing efficiency. Therefore, quick isolation of a fault section is achieved, when a fault occurs, the power failure range is controlled within the minimum range, the power failure time is shortened, fault positioning and control decision making are completely and autonomously completed by the power distribution terminal, the whole processing process does not depend on a power distribution main station, and the main station only needs to receive a fault processing result afterwards; according to the method, the network topology structure can be automatically updated when part of power distribution terminals have communication faults, the operation states of all nodes and circuit breakers in a power distribution line can be monitored in real time, remote measurement can be conducted on voltage, current, power factors and the like, and operation parameter curves of all the nodes can be displayed in real time.

Description

Technical Field

[0001] The present invention belongs to the technical field of distribution network automation and relates to a feeder fault processing system, specifically a feeder fault automation processing system based on a 5G network. Background Art

[0002] Feeder automation is the core component of distribution system automation and the basis for achieving efficient and stable power supply. Distribution system automation covers five main aspects: feeder automation, substation automation, power consumption automation, distribution management automation and automated communication system.

[0003] Among these aspects, feeder automation is of unique importance. Its equipment is distributed in the distribution line and is specifically responsible for fault detection, location, automatic isolation of faulty sections, and restoration of power supply to non-faulty sections. Under normal circumstances, the feeder automation system can monitor the status of feeder section switches and tie switches in real time, as well as the current and voltage of the feeder. Through these real-time data, the system can remotely control the line switches to achieve closing and opening operations, thereby optimizing the operation mode of the distribution network and making full use of the capacity of existing equipment. The system can also quickly obtain fault information when a fault occurs, automatically identify the fault type and isolate the faulty section, and restore power supply to non-faulty areas. This rapid response can significantly reduce the area of ​​power outages and shorten the power outage time. In addition, in abnormal situations such as single-phase grounding, the system can assist in locating the problem area, further improve the reliability and quality of power supply, and reduce the operation and maintenance costs of the distribution network.

[0004] However, the current 10kV distribution network feeder automation faces some problems, including slow response speed, cumbersome operation and low system intelligence. These problems may lead to power outages, low operating efficiency and safety hazards. Therefore, improving the intelligence level and reliability of 10kV distribution network fault handling has become the current research focus.

[0005] At present, feeder automation technology mainly adopts two modes: local type and centralized type. Local feeder automation locates and isolates faulty sections and restores power supply to non-faulty sections through communication, timing or logic coordination between terminals. Its configuration methods include voltage-time type and intelligent distributed type. Voltage-time type usually takes a long time to isolate faults and restore power supply, and is suitable for urban and rural junctions where power supply reliability is not required. Intelligent distributed type has higher requirements for network communication, and generally requires optical fiber Ethernet to achieve fast communication between terminal devices. The centralized feeder automation mode relies on the distribution automation master station to locate the faulty section, isolate the fault and restore power supply to non-faulty areas by collecting fault information from the distribution terminal. The centralized mode has high requirements for network delay, and usually uses optical fiber Ethernet to achieve fast communication between equipment and the master station. Although the communication requirements of intelligent distributed and centralized modes are high, the laying and maintenance costs of optical fiber are high, especially inconvenient to promote in urban areas; while the voltage-time type may take a long time in the fault handling process, and may cause frequent power outages in non-faulty areas, affecting user experience.

[0006] With the development of 5G wireless communication technology, its advantages such as simple and flexible networking, high-speed communication rate, long-distance transmission capability, and high security and reliability provide fast and reliable transmission and timing channels for feeder automation. The high speed, wide coverage, low power consumption, and low latency characteristics of 5G networks make it possible to combine 5G networks with feeder automation technology. This combination will greatly reduce the cost of laying and improve the operation, maintenance, and management level of distribution network automation.

[0007] In traditional distribution networks, feeder automation systems locate faults by monitoring the current size or direction of switches upstream and downstream of the fault point. However, with the access of distributed power sources, fault currents become more complex and currents may flow in multiple directions, causing traditional fault location methods to fail. Therefore, exploring and developing new fault location methods to adapt to complex distribution network environments has become an important research direction. Summary of the invention

[0008] In order to solve the technical problems existing in the background technology, the present invention proposes an automatic feeder fault processing method based on 5G network, which can realize the rapid isolation of the fault section, control the power outage scope to the minimum range, and shorten the power outage time.

[0009] The purpose of the present invention can be achieved by the following technical solutions:

[0010] The feeder fault automatic processing method based on 5G network includes the following steps:

[0011] Step S1, firstly, stipulate that the direction of the inflow current from the power supply side to the load side is the positive direction, and the multiple distribution terminals are numbered in sequence according to the current flow direction, and the multiple distribution terminals and the multiple distribution terminals are connected to the host computer through 5G network communication, and a network topology structure is established, and the topology structure is input into the host computer to form network structure data;

[0012] Step S2: When the communication of a distribution terminal is interrupted, the host computer deletes the topology of the distribution terminal and sends information to the next numbered distribution terminal. The next numbered distribution terminal receives the information and replies to confirm, updates the number and uploads the updated topology information to the host computer. If it is not the terminal distribution terminal, it continues to send information to the adjacent distribution terminal and updates the number, and updates the network topology until it is updated to the terminal distribution terminal, and the network topology update is completed.

[0013] Step S3, when a network fault occurs, data is collected through multiple distribution terminals. When the current collected by the distribution terminal is greater than the set current, it can be regarded as a fault on the line where the distribution terminal is located. Through communication and logical judgment between different distribution terminals, the fault area is determined on the main line;

[0014] Step S4, after the fault area is determined, the fault type is determined, an alarm is sent to the operation and maintenance personnel, and the operation and maintenance personnel are notified to check and handle the fault. The alarm method for sending an alarm to the operation and maintenance personnel includes SMS alarm and mobile application notification.

[0015] Furthermore, the distribution terminal is composed of a lower computer, a circuit breaker and a transformer located in an intelligent terminal box, wherein the transformer is installed on the power supply side of the circuit breaker, that is, the current inflow side. The intelligent terminal box is also provided with an energy storage power supply that can maintain the normal operation of the distribution terminal for a specified time. The circuit breaker is installed at the power substation or distributed power supply outlet or intermediate line node.

[0016] Furthermore, in step S2, when the power distribution terminal operates normally, the operating parameters are uploaded to the host computer, and when the power distribution terminal fails, the parameters and tripping information are uploaded to the host computer.

[0017] Furthermore, in step S3, after data analysis and logical judgment, the circuit breaker action of a certain distribution terminal is determined, and the action information and state parameters at the time of failure are uploaded to the host computer. The host computer can remotely control multiple distribution terminals and manage and schedule network flows at the same time.

[0018] Furthermore, the method for determining the fault type in step S4 includes:

[0019] If there are no other branches containing distributed power sources in the fault area, the upper computer commands the distribution terminal circuit breaker with a smaller number to reclose once. If it is a transient fault, the network current is lower than the set value and returns to normal, and an information alarm is sent to the operation and maintenance personnel; if the current collected by the distribution terminal is still greater than the set value after reclosing once, the distribution terminal circuit breaker is automatically disconnected, and the fault is determined to be a permanent fault, and an information alarm is sent to the operation and maintenance personnel;

[0020] If there are other branches containing distributed power sources in the fault area, the host computer commands the distribution terminal circuit breaker on the distributed power source side to perform a tripping action first, and then commands the distribution terminal circuit breaker with a smaller number on the main line to immediately perform a reclosing action once to determine whether the fault type is a transient fault or a permanent fault.

[0021] Furthermore, in step S1, when the plurality of distribution terminals are numbered, the distribution terminals on the main line are numbered Q according to the current flow direction. i , connect the remaining branches containing distributed power sources, that is, the distribution terminals Q on the main line i and distribution terminal Q i+1 The distribution terminal containing distributed power generation is numbered D according to the current flow direction. i , where i is the number.

[0022] Further, in step S2, when the number is Q k When a communication failure occurs in the power distribution terminal, the next level numbered Q k+1 The distribution terminal is updated to Q k , followed by Q k+2 , Q k+3 ...Q k+i The distribution terminal is updated to Q k+1 , Q k+2 ...Q k+i-1 , and upload the new topology to the host computer.

[0023] Further, in step S2, when the number is Q k When the distribution terminal communication fails, if there is a line numbered D k The distribution terminal is updated to A k-1 , and upload the new topology to the host computer.

[0024] Furthermore, when determining the fault area, first search according to the current flow direction to determine the main line distribution terminal where the overcurrent data is detected. The distribution terminal with the largest number is the basic distribution terminal. If the basic distribution terminal of the main line is numbered Q k , then we assume that Q k-1 , Q k , Q k+1 , D k+1 , Ak-1 , D k As the basic fault area; determine whether the current detected by the circuit breaker is in the positive direction. If it is in a fixed positive direction, calculate the inflow current and outflow current according to Kirchhoff's inflow law. calculate

[0025] in Q k-1 The current phase detected by the power distribution terminal, Q k The current phase detected by the power distribution terminal, D k-1 The current phase detected by the distribution terminal, if If it exceeds the set value, the fault interval is judged to be Q k-1 , Q k and D k-1 , A k-1 In the region composed of If the set value is not exceeded, Q k-1 and Q k+1 For the basic distribution terminal, follow the above steps again to determine the actual fault area.

[0026] Beneficial effects of the present invention: The feeder fault automation processing method provided by the present invention utilizes the high speed, low latency and high security of the 5G communication network to improve the fault handling capability of the distribution system. Through the information exchange between the distribution terminals, the fault signals of itself and the adjacent terminals can be combined to quickly locate the fault area, thereby realizing the rapid isolation of the fault section, so that when a fault occurs, the power outage range is controlled within the minimum range, and the power outage time is also shortened. The fault location and control decisions are completely completed independently by the distribution terminal. The entire processing process does not depend on the distribution master station. The master station only needs to receive the fault handling results afterwards. In addition, the method can automatically update the network topology when some distribution terminals have communication failures, and can also monitor the operating status of each node and circuit breaker in the distribution line in real time, perform telemetry on voltage, current, power factor, etc., and can display the operating parameter curve of each node in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a connection diagram of the distribution terminal in the 10kV distribution network of the present invention.

[0028] Figure 2 It is a schematic diagram of the process of the present invention.

[0029] Figure 3 This is a schematic diagram of updating the topology when handling a fault in the process of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The present invention provides a feeder fault automation processing method based on 5G network, which is used in a 10kV distribution network. The distribution network includes multiple distribution terminals, and the distribution terminal is composed of a lower computer, a circuit breaker and a mutual inductor located in an intelligent terminal box. Figure 1 As shown, multiple distribution terminals are connected to each other in communication, and multiple distribution terminals are connected to the upper computer in communication. A 5G network is established in the line, and the communication between the lower computers and the communication between the lower computer and the upper computer are all completed through the 5G network. Among them, the circuit breaker is installed in each distribution terminal installed in the power substation, distributed power outlet and intermediate line, the mutual inductor is installed on the power supply side of the circuit breaker, that is, the current inflow side, and the intelligent terminal box is also provided with an energy storage power supply that can maintain the normal operation of the equipment for 3 minutes. The upper computer can monitor the operating status of each distribution terminal and circuit breaker in the distribution network in real time, perform telemetry on voltage, current, power factor, etc., and can display the operating parameter curve of each distribution terminal in real time.

[0032] like Figure 2 As shown, the feeder fault automatic processing method includes the following steps:

[0033] Step S1, establishing a network topology.

[0034] First, the direction of the current flowing from the power supply side to the load side is defined as the positive direction, and multiple distribution terminals are numbered according to the positive direction of the current flow, such as Figure 3 As shown, the distribution terminal on the main line is numbered as Q i , the remaining branches containing distributed power sources, that is, at the distribution terminal Q i and Q i+1 The distribution terminal containing distributed power generation is numbered D according to the positive direction of current flow. i , where i is a number, and the above topological structure is input into the host computer to form network structure data.

[0035] Step S2: updating the network topology when a communication failure occurs.

[0036] When the communication of a distribution terminal is interrupted, the host computer deletes the topology of the distribution terminal, sends information to the next numbered distribution terminal and obtains relevant parameters. The next numbered distribution terminal receives the information and replies to confirm, updates the number and uploads the updated topology information to the host computer. If it is not the end distribution terminal, it continues to send information to the adjacent distribution terminal and update the number, updating the network topology until it is updated to the end distribution terminal and the network topology update is completed.

[0037] Specifically, when Figure 3 (A) is numbered Q k When a communication failure occurs in the power distribution terminal, the next level numbered Q k+1 The distribution terminal is updated to Q k , followed by Q k+2 , Q k+3 ...Q k+i The distribution terminal is updated to Q k+1 , Q k+2 ...Q k+i-1 At the same time, the existing number D in the line k The number of the distribution terminal is updated to A k-1 The updated topology is as follows: Figure 3 As shown in (B), the new topology is uploaded to the host computer.

[0038] Step S3, determining the fault area.

[0039] When a network failure occurs, data is collected through multiple distribution terminals. When the current collected by the distribution terminal is greater than the set current, it can be considered that a fault has occurred on this line. Through communication and logical judgment between different terminals, the fault area is determined on the main line.

[0040] Specifically, when determining the fault area, first search in the positive direction of the current flow to determine the main line distribution terminal where the overcurrent data is detected, where the distribution terminal with the largest number is the basic distribution terminal. k , then we assume that Q k-1 , Q k , Q k+1 , D k-1 , A k-1 As the basic fault area; determine whether the current detected by the circuit breaker is in the positive direction. If it is in a fixed positive direction, calculate the inflow current and outflow current according to Kirchhoff's current law, as shown in calculate in Q k-1 The current phase detected by the power distribution terminal, Q k The current phase detected by the power distribution terminal, D k-1 The current phase detected by the distribution terminal; if If the set value is exceeded, the set value should be set to the minimum short-circuit current during the fault, then the actual fault interval is determined to be Q k-1 , Q k and D k-1 , A k-1 In the region composed of If the set value is not exceeded, Q k-1 and Q k+1 For the basic distribution terminal, follow the above steps again to determine the actual fault area.

[0041] Step S4, handle the fault and generate an alarm.

[0042] After the real fault area is determined, the fault type is judged as a transient fault or a permanent fault, and the operation and maintenance personnel are alerted via SMS alarm and mobile application notification alarm to check the cause of the fault in time.

[0043] The specific operations for determining the fault type are as follows:

[0044] If there are no other branches containing distributed generation in the fault area, that is, no D k-1 , A k-1 When the power distribution terminal circuit breaker is connected, the host computer commands the main line power distribution terminal Q with a smaller number k-1 The circuit breaker is reclosed once; if it is a transient fault, the network current is lower than the set value and returns to normal, and an information alarm is sent to the operation and maintenance personnel; if the current collected by the distribution terminal is still greater than the set value after reclosing once, the circuit breaker of the distribution terminal is automatically disconnected, and the fault is determined to be a permanent fault, and an information alarm is sent to the operation and maintenance personnel.

[0045] If there are other branches containing distributed generation in the fault area, that is, branches containing D k-1 , A k-1 When the power distribution terminal circuit breaker is on, the host computer commands the power distribution terminal D on the distributed power supply side. k-1 , A k-1 The circuit breaker of the main line will trip first, and then the main line distribution terminal Q k-1 The circuit breaker immediately performs reclosing once, determines whether the fault type is a transient fault or a permanent fault, and uploads each action information and state parameters at the time of the fault to the host computer.

[0046] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. The method for automatically handling feeder faults based on 5G network is characterized in that: The steps include: Step S1, multiple power distribution terminals are numbered in sequence according to the current flow direction, multiple power distribution terminals and multiple power distribution terminals and a host computer are connected through 5G network communication, a network topology structure is established, and the topology structure is input into the host computer to form network structure data; Step S2: When the communication of a distribution terminal is interrupted, the host computer deletes the topology of the distribution terminal and sends information to the next numbered distribution terminal. The next numbered distribution terminal receives the information and replies to confirm, updates the number and uploads the updated topology information to the host computer. If it is not the terminal distribution terminal, it continues to send information to the adjacent distribution terminal and updates the number, and updates the network topology until it is updated to the terminal distribution terminal, and the network topology update is completed. Step S3, when a network fault occurs, data is collected through multiple distribution terminals. When the current collected by the distribution terminal is greater than the set current, it can be regarded as a fault on the line where the distribution terminal is located. Through communication and logical judgment between different distribution terminals, the fault area is determined on the main line; Step S4, after the fault area is determined, the fault type is determined, an alarm is sent to the operation and maintenance personnel, and the operation and maintenance personnel are notified to check and handle the fault.

2. The feeder fault automatic processing method according to claim 1, characterized in that: The power distribution terminal is composed of a lower computer, a circuit breaker and a transformer located in an intelligent terminal box. The transformer is installed on the power supply side of the circuit breaker, that is, the current inflow side. The intelligent terminal box is also equipped with an energy storage power supply that can maintain the normal operation of the power distribution terminal for a specified time.

3. The feeder fault automatic processing method according to claim 1, characterized in that: In step S2, when the power distribution terminal operates normally, the operating parameters are uploaded to the host computer, and when the power distribution terminal fails, the parameters and tripping information are uploaded to the host computer.

4. The feeder fault automatic processing method according to claim 1, characterized in that: In step S3, after data analysis and logical judgment, the circuit breaker action of a certain distribution terminal is determined, and the action information and state parameters at the time of failure are uploaded to the host computer. The host computer can remotely control multiple distribution terminals and manage and schedule network flows at the same time.

5. The feeder fault automatic processing method according to claim 1, characterized in that: The method for determining the fault type in step S4 includes: If there are no other branches containing distributed power sources in the fault area, the upper computer commands the distribution terminal circuit breaker with a smaller number to reclose once. If it is a transient fault, the network current is lower than the set value and returns to normal, and an information alarm is sent to the operation and maintenance personnel; if the current collected by the distribution terminal is still greater than the set value after reclosing once, the distribution terminal circuit breaker is automatically disconnected, and the fault is determined to be a permanent fault, and an information alarm is sent to the operation and maintenance personnel; If there are other branches containing distributed power sources in the fault area, the host computer commands the distribution terminal circuit breaker on the distributed power source side to perform a tripping action first, and then commands the distribution terminal circuit breaker with a smaller number on the main line to immediately perform a reclosing action once to determine whether the fault type is a transient fault or a permanent fault.

6. The feeder fault automatic processing method according to claim 1, characterized in that: In step S1, when multiple distribution terminals are numbered, the distribution terminals on the main line are numbered Q according to the current flow direction. i , connect the remaining branches containing distributed power sources, that is, the distribution terminals Q on the main line i and distribution terminal Q i+1 The distribution terminal containing distributed power generation is numbered D according to the current flow direction. i , where i is the number.

7. The feeder fault automatic processing method according to claim 6, characterized in that: In step S2, when the number is Q k When a communication failure occurs in the power distribution terminal, the next level numbered Q k+1 The distribution terminal is updated to Q k , followed by Q k+2 , Q k+3 ...Q k+i The distribution terminal is updated to Q k+1 , Q k+2 ...Q k+i-1 , and upload the new topology to the host computer.

8. The feeder fault automatic processing method according to claim 7, characterized in that: In step S2, when the number is Q k When the distribution terminal communication fails, if there is a line numbered D k The distribution terminal is updated to A k-1 , and upload the new topology to the host computer.

9. The feeder fault automatic processing method according to claim 8, characterized in that: When determining the fault area, first search according to the current flow direction to determine the main line distribution terminal where overcurrent data is detected. The distribution terminal with the largest number is the basic distribution terminal. If the basic distribution terminal of the main line is numbered Q k , then we assume that Q k-1 , Q k , Q k+1 , Q k-1 , A k-1 , D k As the basic fault area; determine whether the current detected by the circuit breaker is in the positive direction. If it is in a fixed positive direction, calculate the inflow current and outflow current according to Kirchhoff's inflow law. calculate in Q k-1 The current phase detected by the power distribution terminal, Q k The current phase detected by the power distribution terminal, D k-1 The current phase detected by the distribution terminal, if If it exceeds the set value, the fault interval is judged to be Q k-1 , Q k and D k-1 , A k-1 In the region composed of If the set value is not exceeded, Q k-1 and Q k+1 For the basic distribution terminal, follow the above steps again to determine the actual fault area.

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