A regional protection reclosing method based on distributed new energy access

Abstract

The present invention discloses a regional protection reclosing method based on distributed new energy access, including: the main machine is installed at the outgoing circuit breaker, the sub-machine is installed at each distributed new energy branch and load branch, and the main machine and each sub-machine communicate through a wireless channel; if the values ​​of the trip relays received by all sub-machines are 1, the longitudinal reclosing switch is fully charged, there is no current, and the longitudinal protection is tripped, the main machine determines to execute the start of the longitudinal reclosing switch. If the longitudinal reclosing switch start and reclosing switch synchronous voltage conditions are met at the same time, the delay t triggers the longitudinal reclosing switch action and triggers the host reclosing switch outlet. Through the comprehensive judgment of the longitudinal reclosing switch, the reclosing accuracy is improved, thereby improving the regional power supply reliability of the distributed new energy network.

Description

Technical Field

[0001] The invention relates to a regional protection reclosing method based on distributed new energy access, belonging to the technical field of power system relays. Background Art

[0002] With the proposal of the dual carbon goals, the construction of new energy power generation has entered every corner of my country's power grid construction. Among them, distributed photovoltaics are the most prominent, but with the grid connection of distributed photovoltaics and other new energy generators, a large number of distributed new energy generators and users share a transmission and distribution line. In areas rich in new energy resources such as wind and light, there will be multiple distributed power generation projects connected to the same transmission line. The existing protection and control technology is limited by factors such as signal transmission channels, point-to-point communication transmission, and the inability to integrate intelligent control. It is impossible to achieve regional protection reclosing in the distributed energy area of ​​the distribution network. When the sub-line system of the distributed new energy grid-connected line fails, each branch determines the reclosing logic. Most new energy branch faults are permanent faults. If the protection is reclosed, it will cause a secondary impact on the system; while transmission and distribution line faults are mostly instantaneous faults, and the power supply reliability needs to be improved through the reclosing function. However, relying solely on the reclosing logic of each feeder protection itself cannot take into account both sides of the contradiction. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a regional protection reclosing method based on distributed new energy access. By designing a one-master-multiple-slave regional protection reclosing logic, wireless network communication is used to achieve peer-to-peer communication between the host and each slave, which is more convenient for mutual transmission of information of multiple protection devices and transmission of key signal quantities, the regional protection reclosing method is optimized, and the reclosing function is maximized to improve power supply reliability.

[0004] To achieve the above object, the present invention provides a regional protection reclosing method based on distributed renewable energy access, comprising:

[0005] The host is installed at the outgoing circuit breaker, and the slave is installed at each distributed new energy branch and load branch. The host and each slave communicate through a wireless channel;

[0006] If the values ​​of the trip relays of all slave machines are 1, the longitudinal reclosing switch is fully charged, there is no current, and the longitudinal protection is tripped, the host determines to start the longitudinal reclosing switch.

[0007] Preferentially, if the longitudinal reclosing start-up and reclosing synchronous voltage conditions are met at the same time, the delay t triggers the longitudinal reclosing action and triggers the host reclosing output.

[0008] Prioritize, after the host triggers the longitudinal reclosing action, the t1 time is widened. If the post-acceleration protection is not activated within the widened t1 time, and there is no abnormality in the wireless channel, the host sends the reclosing command after a delay of t2 time and sends it to each slave through the wireless channel, where t1>t2.

[0009] Preferably, each sub-machine performs independent judgment after receiving the reclosing command. If the sub-machine simultaneously meets the following conditions: the longitudinal reclosing switch is fully charged, the trip relay is 1, there is no current, and the wireless channel is put into operation, the sub-machine triggers the reclosing switch output.

[0010] Prior to this, the host determines that the pilot recloser is fully charged only if any of the following conditions are met:

[0011] The longitudinal reclosing switch did not discharge; the host trip relay was 0; the host's own post-closing relay was 1; the longitudinal reclosing switch did not start.

[0012] Prior to this, the host determines that the longitudinal reclosing circuit breaker discharge must meet any of the following conditions:

[0013] The control word for disabling longitudinal reclosing is put into operation; the soft pressure plate for disabling reclosing is put into operation; the discharge conditions for voltage transformer disconnection are met; the discharge conditions for synchronous voltage abnormality are met; the spring has no energy stored and the longitudinal reclosing is not started; the main machine trip relay is 1 and the longitudinal reclosing is not started; the reclosing is locked; manual tripping; permanent tripping of protection; control circuit disconnection; tripping failure; longitudinal reclosing failure; longitudinal reclosing action; wireless channel abnormality.

[0014] Prior to this, the slave unit determines that the pilot recloser is fully charged only when all of the following conditions are met at the same time:

[0015] The slave machine longitudinal reclosing switch did not discharge, the trip relay was 0, the closing relay was 1, and the slave machine reclosing switch did not operate.

[0016] Prioritize that the slave machine longitudinal reclosing circuit breaker has not discharged if any of the following conditions cannot be met:

[0017] The sub-machine reclosing action; the wireless channel is abnormal; the spring has no energy storage; the manual trip; the protection is permanently tripped; the control circuit is broken; the sub-machine is a distributed new energy branch and the sub-machine overcurrent protection is activated and the post-expansion t3 time is met.

[0018] An electronic device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the above methods when executing the program.

[0019] A computer-readable storage medium stores a computer program, which implements the steps of any of the above methods when executed by a processor.

[0020] The beneficial effects achieved by the present invention are:

[0021] (1) Applicable to distribution network lines with new energy branches. The main machine collects the signal quantity of each slave machine, comprehensively executes the longitudinal reclosing logic judgment, and sends the reclosing signal to the slave machine.

[0022] (2) The slave receives the reclosing signal from the master and implements reclosing logic judgment based on its own collected information.

[0023] (3) For instantaneous faults in the transmission and distribution lines, the branches can be automatically reclosed. For permanent faults in the transmission and distribution lines, the sub-machines will not be reclosed. For faults in the branches on the renewable energy side, the reclosing function of the sub-machine on this branch will be temporarily locked, but it will not affect the reclosing of sub-machines on other branches.

[0024] By adopting the method of the present invention, the accuracy of reclosing is improved through comprehensive judgment of longitudinal reclosing, thereby improving the regional power supply reliability of the distributed new energy network. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a logical schematic diagram of the present invention;

[0026] Figure 2 It is a logic diagram of the host computer of the present invention;

[0027] Figure 3 It is a logic diagram of the slave of the present invention;

[0028] Figure 4 It is a schematic diagram of the distributed new energy network topology structure described in the present invention. DETAILED DESCRIPTION

[0029] The following embodiments are only used to more clearly illustrate the technical solutions of the present invention, and are not intended to limit the protection scope of the present invention.

[0030] With the development and improvement of wireless network communication technology, wireless communication can achieve fast and reliable data interaction with millisecond-level delay and has high signal transmission quality, which can fully meet the application requirements of protection control signal transmission for communication channels. The advantages of wireless network communication in signal transmission provide new solutions to the problems existing in distributed new energy networks. Through wireless network communication, signal quantity communication between feeder protections can be realized, and the logical coordination of feeder protection in reclosing function can be realized. By developing a regional protection reclosing method based on distributed new energy access, the contradiction between the need for reclosing of transmission and distribution line faults and the non-reclosing of new energy branch faults can be solved, and the optimization method of regional protection reclosing can be realized to improve power supply reliability.

[0031] Regional protection devices are divided into two types of devices: host and slave. In the distributed new energy network, the host is installed on the outgoing circuit breaker, and the slave is installed on each distributed new energy branch and load branch. There is one host and multiple slaves in a distributed new energy network.

[0032] Each host or slave is connected to its own wireless communication terminal through optical fiber or network cable. The host transmits information to each slave through the 5G wireless channel, and the slaves do not communicate with each other.

[0033] The host machine distinguishes the start and action logic of the longitudinal reclosing. When the values ​​of the trip relays (TWJ) receiving all slave machines are 1, the longitudinal reclosing is fully charged, there is no current, and the longitudinal protection is tripped, the longitudinal reclosing is judged to be started; after the longitudinal reclosing is started, when the synchronous voltage conditions of the reclosing are met, the delay t triggers the longitudinal reclosing action and triggers the host reclosing output; t can be set by the reclosing time setting.

[0034] After the host triggers the longitudinal reclosing action, it will be extended by 4s. If there is no post-acceleration protection started during this period and there is no 5G wireless channel abnormality, the host will send a reclosing command after a delay of 3s and send it to each slave through the 5G wireless channel.

[0035] After receiving the reclosing command through the 5G wireless channel, the sub-machine will make independent judgments. If the sub-machine simultaneously meets the conditions that the longitudinal reclosing switch is fully charged, the sub-machine's own trip relay (TWJ) is 1, there is no current, and the 5G wireless channel is put into operation, the sub-machine will trigger the sub-machine reclosing outlet.

[0036] The conditions for the host to judge that the longitudinal reclosing switch is fully charged are that there is no discharge of the longitudinal reclosing switch, the host's trip relay is 0, the host's after-closing relay is 1, and there is no longitudinal reclosing switch started. After the above conditions are met, it will be judged that the longitudinal reclosing switch is fully charged after a delay of 15s.

[0037] The host determines that the conditions for the longitudinal reclosing to discharge are any of the following conditions: the control word for disabling the longitudinal reclosing is put into operation, the soft pressure plate for disabling the reclosing is put into operation, the discharge conditions for the voltage transformer break are met, the discharge conditions for the synchronous voltage abnormality are met, the spring has no energy stored and the longitudinal reclosing is not started, the host trip relay is 1 and the longitudinal reclosing is not started, the reclosing is locked, the manual trip, the permanent trip of the protection, the control circuit is broken, the tripping fails, the longitudinal reclosing fails, the longitudinal reclosing operates, and the wireless channel is abnormal.

[0038] To determine whether the slave machine longitudinal reclosing switch is fully charged, the following conditions must be met at the same time: the slave machine has no longitudinal reclosing switch discharge, the trip relay is 0, the relay after closing is 1, and there is no slave machine reclosing switch action. After the above conditions are met, it will be judged that the longitudinal reclosing switch is fully charged after a delay of 15s.

[0039] The condition for the slave machine to determine the discharge of the longitudinal reclosing switch is to meet any of the following conditions: the slave machine reclosing switch is actuated, the wireless channel is abnormal, the spring has no energy storage, manual tripping, permanent protection tripping, control circuit disconnection, the slave machine is a distributed new energy branch and the slave machine overcurrent protection is activated. If all the conditions are met at the same time, the time will be extended by 10 minutes.

[0040] The wireless channel in the present invention adopts 5G technology, and the regional protection device is divided into two types of devices: a host and a slave. One host is matched with multiple slaves. Both the host and the slave support the Ethernet standard communication protocol and can send and receive wireless data by matching with a wireless communication terminal, such as Figure 4 As shown, a wireless communication module can also be integrated to perform wireless data conversion inside the area protection device.

[0041] An electronic device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the above methods when executing the program.

[0042] A computer-readable storage medium stores a computer program, which implements the steps of any of the above methods when executed by a processor.

[0043] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0044] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0045] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0046] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A regional protection reclosing method based on distributed new energy access, characterized in that: include: The host is installed at the outgoing circuit breaker, and the slave is installed at each distributed new energy branch and load branch. The host and each slave communicate through a wireless channel; If the values ​​of the trip relays of all slave units are 1, the pilot reclosing switch is fully charged, there is no current, and the pilot protection is tripped, the host determines to start the pilot reclosing switch; After receiving the reclosing order sent by the host, each slave machine makes an independent judgment. If the slave machine simultaneously meets the conditions that the longitudinal reclosing switch is fully charged, the trip relay is 1, there is no current, and the wireless channel is put into operation, the slave machine will trigger the reclosing switch output.

2. A regional protection reclosing method based on distributed renewable energy access according to claim 1, characterized in that: If the longitudinal reclosing start-up and reclosing synchronous voltage conditions are met at the same time, the delay t will trigger the longitudinal reclosing action and trigger the host reclosing output.

3. A regional protection reclosing method based on distributed new energy access according to claim 2, characterized in that: After the host triggers the longitudinal reclosing action, the t1 time is extended. If the post-acceleration protection is not activated within the extended t1 time, and there is no abnormality in the wireless channel, the host sends a reclosing command after a delay of t2 time and sends it to each slave through the wireless channel, where t1>t2.

4. A regional protection reclosing method based on distributed new energy access according to claim 1, characterized in that: The host determines that the longitudinal reclosing circuit breaker is fully charged only if any of the following conditions are met: The longitudinal reclosing switch did not discharge; the host trip relay was 0; the host's post-closing relay was 1; the longitudinal reclosing switch did not start.

5. A regional protection reclosing method based on distributed renewable energy access according to claim 4, characterized in that: The host determines that the longitudinal reclosing circuit breaker discharges when any of the following conditions are met: The control word for disabling longitudinal reclosing is enabled; the soft pressure plate for disabling reclosing is enabled; the discharge conditions for voltage transformer disconnection are met; the discharge conditions for synchronous voltage abnormality are met; the spring has no energy storage and the longitudinal reclosing is not started; the main machine trip relay is 1 and the longitudinal reclosing is not started; the reclosing is locked; Manual trip; permanent trip of protection; disconnection of control circuit; tripping failure; longitudinal reclosing failure; longitudinal reclosing action; abnormality of wireless channel.

6. A regional protection reclosing method based on distributed renewable energy access according to claim 1, characterized in that: The slave unit determines that the longitudinal reclosing circuit breaker is fully charged only when all the following conditions are met: The slave machine longitudinal reclosing switch did not discharge, the trip relay was 0, the closing relay was 1, and the slave machine reclosing switch did not operate.

7. A regional protection reclosing method based on distributed renewable energy access according to claim 6, characterized in that: To determine that the slave machine longitudinal reclosing circuit breaker has not discharged, any of the following conditions must not be met: The sub-machine reclosing action; the wireless channel is abnormal; the spring has no energy storage; the manual trip; the protection is permanently tripped; the control circuit is broken; the sub-machine is a distributed new energy branch and the sub-machine overcurrent protection is activated and the post-expansion t3 time is met.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the method according to any one of claims 1 to 7 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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