阅读说明：本技术 一种基于无线通信的配电网自适应差动保护自愈方法 (Self-healing method for power distribution network self-adaptive differential protection based on wireless communication ) 是由 陈宏山 余江 乔峰 徐骏 缪秋滚 汤斐挺 许健 孙泉 陆明 史泽兵 高宏慧 万 于 2021-07-12 设计创作，主要内容包括：一种基于无线通信的配电网自适应差动保护自愈方法,其特征在于,包括以下步骤：步骤1,基于无线通信系统连接的智能分布式平台,多个智能分布式终端DTU中的一个基于采样点插值同步法和IRIG全局对时法接收并同步来自其他DTU的差动保护数据,以检测所述智能分布式平台中的差动电流；步骤2,基于所述差动电流依次检测所述平台中的过流开关,待检测到过流断路器后对所述过流断路器执行跳闸操作以实现故障隔离；步骤3,待故障隔离完成,所述故障点下游开关向下游侧传送遥信,并基于联络开关数据和自愈策略选择最优的负荷转供方案。本发明中的方案能够实现配电网运行状态的监视控制和配电网故障的快速定位、隔离与恢复,可靠性高、成本低。(A self-healing method of power distribution network self-adaptive differential protection based on wireless communication is characterized by comprising the following steps: step 1, based on an intelligent distributed platform connected by a wireless communication system, one of a plurality of intelligent distributed terminal DTUs receives and synchronizes differential protection data from other DTUs based on a sampling point interpolation synchronization method and an IRIG global time synchronization method so as to detect differential current in the intelligent distributed platform; step 2, sequentially detecting overcurrent switches in the platform based on the differential current, and performing tripping operation on the overcurrent breakers after the overcurrent breakers are detected to realize fault isolation; and 3, after the fault isolation is completed, transmitting a remote signal to the downstream side by the downstream switch of the fault point, and selecting an optimal load transfer scheme based on the data of the interconnection switch and the self-healing strategy. The scheme of the invention can realize the monitoring control of the running state of the power distribution network and the rapid positioning, isolation and recovery of the fault of the power distribution network, and has high reliability and low cost.)

1. A self-healing method of power distribution network self-adaptive differential protection based on wireless communication is characterized by comprising the following steps:

step 1, based on an intelligent distributed platform connected by a wireless communication system, one of a plurality of intelligent distributed terminal DTUs receives and synchronizes differential protection data from other intelligent distributed terminal DTUs based on a sampling point interpolation synchronization method and an IRIG global time synchronization method so as to detect differential current in the intelligent distributed platform;

step 2, sequentially detecting overcurrent switches in the platform based on the differential current, and performing tripping operation on the overcurrent breakers after the overcurrent breakers are detected to realize fault isolation;

and 3, after the fault isolation is completed, transmitting a remote signal to the downstream side by the downstream switch of the fault point, and selecting an optimal load transfer scheme based on the data of the interconnection switch and the self-healing strategy.

2. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication as claimed in claim 1, wherein:

the intelligent distributed platform comprises a plurality of power distribution master stations connected based on a wireless communication system;

the power distribution main station comprises an intelligent distributed terminal DTU and is used for connecting the intelligent distributed terminal DTU to CPE in the wireless communication system;

the intelligent distributed terminal DTU is connected to a wireless communication system based on CPE and sends or receives the differential protection data based on CPE.

3. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication as claimed in claim 1, wherein:

the sampling point interpolation synchronization method specifically comprises the following steps:

step 1.1, the receiving end DTU receives differential protection data from the sending end DTU, and calculates sampling time of the sending end DTU based on time scale data in the differential protection data;

step 1.2, the receiving end DTU recovers the analog quantity of the differential protection data collected by the sending end DTU based on the sampling time and the sampling value;

and step 1.3, the receiving end DTU generates interpolation point information based on a local clock, and performs interpolation operation on the differential protection data of the sending end DTU based on the interpolation point information and the analog quantity of the differential protection data, so as to synchronize the differential protection data of the sending end DTU to the receiving end DTU.

4. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication as claimed in claim 1, wherein:

the step 2 further comprises the following steps:

step 2.1, judging the type of the current switch where the differential current is located;

step 2.2, if the current switch is a breaker, executing tripping operation, and if the current switch is a load switch, detecting the overcurrent state of an adjacent switch in the local ring main unit;

step 2.3, if the adjacent switch is in an overcurrent state, continuously judging the type of the adjacent switch;

and 2.4, if the adjacent switch is a breaker, executing tripping operation, if the adjacent switch is a load switch, continuously searching the next adjacent switch in the upstream direction, and repeating the step 2.3 and the step 2.4 until the overcurrent breaker is found, and executing tripping operation on the overcurrent breaker.

5. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication as claimed in claim 1, wherein:

the step 3 further comprises:

after fault isolation is realized, the downstream switch of the fault point sends a remote signaling of successful isolation to the downstream;

after all tie switches positioned on the downstream side of the downstream switch of the fault point receive the isolation success remote signaling, the opposite-side index of the tie switches is transmitted back to the downstream switch of the fault point;

and the downstream switch of the fault point selects the opposite-side indexes returned by all the interconnection switches based on a self-healing strategy so as to obtain the optimal interconnection switch.

6. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication as claimed in claim 5, wherein:

and the interconnection switch is used for transmitting the power supply residual capacity value data to the opposite side after receiving the power supply information of one side.

7. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication as claimed in claim 5, wherein:

the contralateral indices include: the value of the remaining capacity of the side power supply, the switching priority of the interconnection switch and the recovery delay time.

8. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication as claimed in claim 1, wherein:

the step 3 further comprises:

the downstream switch of the fault point generates an optimal load transfer scheme based on the optimal interconnection switch;

and the downstream switch of the fault point sends the optimal load transfer scheme to a related interconnection switch, and after receiving the load transfer scheme, the related interconnection switch executes closing operation according to the scheme.

9. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication as claimed in claim 1, wherein:

the intelligent distributed platform also comprises a distribution automation master station system, and the distribution automation master station system is used for periodically detecting system topology change and generating an SCD file;

wherein the system topology change is caused by the intelligent distributed platform executing the load transfer scheme.

10. The self-healing method for the adaptive differential protection of the power distribution network based on the wireless communication according to claim 9, wherein:

the SCD file is used for adaptively updating GOOSE and SV configuration files in the DTU of the intelligent distributed terminal in the intelligent distributed platform;

the GOOSE and SV configuration files are used for configuring the collected data of the intelligent distributed terminal DTU into differential protection data for transmission, or for analyzing the received differential protection data from other intelligent distributed terminal DTUs.

Technical Field

The invention relates to the field of power distribution of a power system, in particular to a self-healing method of self-adaptive differential protection of a power distribution network based on wireless communication.

Background

At present, as a large number of distributed power supplies are connected into a power distribution network, the fault current level and the power flow direction of the power distribution network are greatly changed. The traditional three-section type overcurrent protection is difficult to meet the index requirement of power distribution network protection. The line current differential protection has high action speed and high reliability, and can accurately position and quickly remove the faults of the power distribution network.

However, the optical fiber differential protection scheme is difficult to implement due to the problems that the optical fiber laying cost in urban areas is too high, no optical fiber coverage exists at distribution points and the like, and the implementation cost is high and is difficult. Although the technical scheme of using a wireless communication system to realize differential protection exists in the prior art, the prior scheme has the disadvantages of low reliability, heavy workload, easy occurrence of communication abnormity, slow self-healing recovery time and difficult guarantee of time synchronization between devices.

Therefore, a new self-healing method for adaptive differential protection of a power distribution network based on wireless communication is needed.

Disclosure of Invention

In order to solve the defects in the prior art, the invention aims to provide a power distribution network self-adaptive differential protection self-healing method based on wireless communication, which can synchronize differential protection data among a plurality of different intelligent distributed terminal devices in a platform, realize fault isolation based on detection of an overcurrent breaker, and select an optimal load transfer scheme based on contact switch data and a self-healing strategy.

The invention adopts the following technical scheme.

A self-healing method of power distribution network self-adaptive differential protection based on wireless communication comprises the following steps: step 1, based on an intelligent distributed platform connected by a wireless communication system, one of a plurality of intelligent distributed terminal DTUs receives and synchronizes differential protection data from other intelligent distributed terminal DTUs based on a sampling point interpolation synchronization method and an IRIG global time synchronization method so as to detect differential current in the intelligent distributed platform; step 2, sequentially detecting overcurrent switches in the platform based on the differential current, and performing tripping operation on the overcurrent breakers after the overcurrent breakers are detected to realize fault isolation; and 3, after the fault isolation is completed, transmitting a remote signal to the downstream side by the downstream switch of the fault point, and selecting an optimal load transfer scheme based on the data of the interconnection switch and the self-healing strategy.

Preferably, the intelligent distributed platform comprises a plurality of power distribution master stations connected based on a wireless communication system; the power distribution main station comprises an intelligent distributed terminal DTU and is used for connecting the intelligent distributed terminal DTU to CPE in the wireless communication system; the intelligent distributed terminal DTU is connected to a wireless communication system based on the CPE and sends or receives differential protection data based on the CPE.

Preferably, the sampling point interpolation synchronization method specifically includes: step 1.1, a receiving end DTU receives differential protection data from a sending end DTU, and calculates sampling time of the sending end DTU based on time scale data in the differential protection data; step 1.2, the receiving end DTU recovers the analog quantity of the differential protection data collected by the sending end DTU based on the sampling time and the sampling value; and step 1.3, the receiving end DTU generates interpolation point information based on the local clock, and performs interpolation operation on the differential protection data of the sending end DTU based on the interpolation point information and the analog quantity of the differential protection data, so that the differential protection data of the sending end DTU is synchronized to the receiving end DTU.

Preferably, step 2 further comprises: step 2.1, judging the type of the current switch where the differential current is located; step 2.2, if the current switch is a breaker, executing tripping operation, and if the current switch is a load switch, detecting the overcurrent state of an adjacent switch in the local ring main unit; step 2.3, if the adjacent switch is in an overcurrent state, continuously judging the type of the adjacent switch; and 2.4, if the adjacent switch is a breaker, executing tripping operation, if the adjacent switch is a load switch, continuously searching the next adjacent switch in the upstream direction, and repeating the step 2.3 and the step 2.4 until the overcurrent breaker is found, and executing tripping operation on the overcurrent breaker.

Preferably, step 3 further comprises: after fault isolation is realized, a fault point downstream switch sends a remote signaling of successful isolation to the downstream; after all tie switches positioned on the downstream side of the downstream switch of the fault point receive the remote signals of successful isolation, the opposite-side indexes of the tie switches are transmitted back to the downstream switch of the fault point; and the downstream switch of the fault point selects the opposite-side indexes returned by all the interconnection switches based on a self-healing strategy so as to obtain the optimal interconnection switch.

Preferably, the interconnection switch is configured to transmit the power supply remaining capacity value data to the opposite side after receiving the power supply information of the one side.

Preferably, contralateral criteria include: the value of the residual capacity of the side power supply, the switching priority of the interconnection switch and the recovery delay time.

Preferably, step 3 further comprises: the downstream switch of the fault point generates an optimal load transfer scheme based on the optimal interconnection switch; and the downstream switch of the fault point sends the optimal load transfer scheme to the related interconnection switch, and the related interconnection switch executes closing operation according to the scheme after receiving the load transfer scheme.

Preferably, the intelligent distributed platform further comprises a power distribution automation master station system, and the power distribution automation master station system is used for regularly detecting system topology changes and generating an SCD file; wherein, the system topology change is caused by the intelligent distributed platform executing the load transfer scheme.

Preferably, the SCD file is used for adaptively updating GOOSE and SV configuration files in a DTU of the intelligent distributed terminal in the intelligent distributed platform; the GOOSE and SV configuration files are used for configuring the collected data of the intelligent distributed terminal DTU into differential protection data for transmission, or for analyzing the received differential protection data from other intelligent distributed terminals DTUs.

Compared with the prior art, the self-healing method for the self-adaptive differential protection of the power distribution network based on the wireless communication has the beneficial effects that the monitoring control of the running state of the power distribution network and the rapid positioning, isolation and recovery of the fault of the power distribution network can be realized. Compared with the prior art, the scheme provided by the invention has the advantages of high reliability and low cost.

The beneficial effects of the invention also include:

1. the problem of frequent transformation of the power distribution network in the prior art is solved, and the workload of operation and maintenance debugging is greatly reduced by adaptively adjusting the topological model and the relevant parameters in the model;

2. the power supply recovery of a millisecond-level non-fault area is realized by utilizing a distributed self-healing technology, and the power failure time is shortened;

3. the sampling point interpolation synchronization technology based on global time synchronization is utilized to realize accurate positioning of the power distribution network fault in an unstable communication environment; meanwhile, reliable fault location within 70ms of the power distribution network is achieved by utilizing a 5G communication network environment with large bandwidth.

Drawings

Fig. 1 is a schematic diagram of a method flow in a self-healing method for power distribution network adaptive differential protection based on wireless communication according to the present invention;

fig. 2 is a schematic network topology diagram of an intelligent distributed platform in the self-healing method for self-adaptive differential protection of a power distribution network based on wireless communication according to the present invention;

fig. 3 is a schematic diagram illustrating a principle of a sampling point interpolation synchronization method in the self-adaptive differential protection self-healing method for the power distribution network based on wireless communication according to the present invention;

fig. 4 is a flowchart of a method for detecting an overcurrent breaker in a power distribution network adaptive differential protection self-healing method based on wireless communication according to the present invention;

fig. 5 is a schematic diagram of a judgment logic of a tie switch in the self-healing method for self-adaptive differential protection of a power distribution network based on wireless communication according to the present invention;

fig. 6 is a schematic diagram of the logic of transfer power supply in the power distribution network adaptive differential protection self-healing method based on wireless communication according to the present invention;

fig. 7 is a schematic diagram of a topology adaptive interface of a distribution network master station in the self-healing method for self-adaptive differential protection of a distribution network based on wireless communication according to the present invention;

fig. 8 is a schematic network topology diagram of an intelligent distributed platform in an embodiment of a self-healing method for self-adaptive differential protection of a power distribution network based on wireless communication.

Detailed Description

The present application is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present application is not limited thereby.

Fig. 1 is a schematic diagram of a method flow in a self-healing method of power distribution network adaptive differential protection based on wireless communication according to the present invention. As shown in fig. 1, a self-healing method for adaptive differential protection of a power distribution network based on wireless communication includes steps 1 to 3.

Step 1, based on an intelligent distributed platform connected by a wireless communication system, one of a plurality of intelligent distributed terminal DTUs receives and synchronizes differential protection data from other intelligent distributed terminal DTUs based on a sampling point interpolation synchronization method and an IRIG global time synchronization method so as to detect differential current in the intelligent distributed platform.

Preferably, the intelligent distributed platform comprises a plurality of power distribution master stations connected based on a wireless communication system; the power distribution main station comprises an intelligent distributed terminal DTU and is used for connecting the intelligent distributed terminal DTU to CPE in the wireless communication system; the intelligent distributed terminal DTU is connected to a wireless communication system based on the CPE and sends or receives differential protection data based on the CPE.

Fig. 2 is a schematic network topology diagram of an intelligent distributed platform in the self-healing method for self-adaptive differential protection of a power distribution network based on wireless communication. As shown in fig. 2, the method in the present invention may be a self-healing system for adaptive distributed differential protection of a power distribution network based on 5G wireless communication, where the system is capable of carrying data related to power distribution automation and data related to adaptive differential protection. From a business perspective, the traffic in the system may include distribution automation traffic and differential protection traffic. In terms of a cylinder communication network, the system can be divided into a protection network, an automation network and a time synchronization network. The protection network is used for realizing fault positioning and isolating functions based on distributed differential protection. The automation network can be used for completing the three-remote function of power distribution automation, the issuing of the global network topology information scd file, the control of related protection commands and the like. The time synchronization network is used for carrying out time synchronization and sampling frequency synchronization on a plurality of wireless DTU terminals. Specifically, the system can be formed by a single power distribution master station and a plurality of intelligent distributed terminals integrating protection, measurement and control through a 5G wireless network on the basis of a multi-service transmission communication platform.

Under the IEC61968/61970 standard framework, the self-adaptive distribution network master station takes a CIM (City Information Modeling) model as a support, extracts the topological structure Information of the distribution network in real time, quickly tracks the topological change, realizes the updating of the model of the intelligent distributed terminal influenced by the topological change and the publishing subscription relationship, realizes self-adaptive differential protection, realizes quick fault positioning and search isolation, and simultaneously realizes the self-healing of the distribution network and the recovery of power supply in a non-fault area through peer-to-peer communication between adjacent terminals after the isolation is successful.

One of the intelligent distributed terminal DTUs receives and synchronizes differential protection data from other intelligent distributed terminal DTUs based on a sampling point interpolation synchronization method and an IRIG global time synchronization method. Preferably, the sampling point interpolation synchronization method specifically includes: step 1.1, a receiving end DTU receives differential protection data from a sending end DTU, and calculates sampling time of the sending end DTU based on time scale data in the differential protection data; step 1.2, the receiving end DTU recovers the analog quantity of the differential protection data collected by the sending end DTU based on the sampling time and the sampling value; and step 1.3, the receiving end DTU generates interpolation point information based on the local clock, and performs interpolation operation on the differential protection data of the sending end DTU based on the interpolation point information and the analog quantity of the differential protection data, so that the differential protection data of the sending end DTU is synchronized to the receiving end DTU.

Fig. 3 is a schematic diagram illustrating a principle of a sampling point interpolation synchronization method in the self-adaptive differential protection self-healing method for the power distribution network based on wireless communication. As shown in fig. 3, the conventional differential protection generally uses the ping-pong principle to adjust the sampling time, so that the DTUs participating in the two-terminal protection sample at the same time. The method can realize the synchronization of the two-end system without depending on an external clock. However, as the number of DTUs in the system increases to three-or multi-terminal systems, both device communication interface and channel operation and maintenance add complexity. In order to realize the differential protection function of the power distribution network, the invention can adopt a sampling point interpolation synchronization method to realize that the two-end or multi-end DTU equipment for differential protection backtracks the data of synchronous sampling time under the condition that no master equipment and slave equipment are arranged.

As shown in step 1.1 to step 1.3, the sampling point interpolation synchronization method generally follows the principle that the DTU on the local side, which needs to use other DTUs for sampling, performs interpolation synchronization on the sampling data sent by other DTUs. The DTU device on the local side can calculate the sampling time on the opposite side according to the received data on the opposite side and the time scale data carried in the data on the opposite side. And then, synchronizing the data on the two sides by adopting an interpolation synchronization method according to the sampling interval of the side.

The time stamp carried in the message on the opposite side indicates the delay time from when the sample value is sampled from one side to when it is sent from the device. In the method of the present invention, the residual differential protection data and different DTU devices have the same time reference frame, and the time reference frame is used as the global time, so that interpolation point information can be regenerated, and interpolation operation can be performed based on the information.

Specifically, the data synchronization may use a B format in an IRIG (range Instrumentation Group) time-coding sequence as a global time synchronization technique. The technology can solve the synchronization problem of the differential protection data of the multi-end line, and also can solve the data synchronization problem of regional differential protection. For the problem of unstable channel transmission delay, the sampling buffer protected on each side can be increased to cover the maximum delay of the channel. Therefore, the differential protection realized by the method can adapt to the analysis of error codes caused by the transmission change of the communication route.

And 2, sequentially detecting the over-current switches in the platform based on the differential current, and performing tripping operation on the over-current circuit breaker after the over-current circuit breaker is detected to realize fault isolation.

Preferably, step 2 further comprises: step 2.1, judging the type of the current switch where the differential current is located; step 2.2, if the current switch is a breaker, executing tripping operation, and if the current switch is a load switch, detecting the overcurrent state of an adjacent switch in the local ring main unit; step 2.3, if the adjacent switch is in an overcurrent state, continuously judging the type of the adjacent switch; and 2.4, if the adjacent switch is a breaker, executing tripping operation, if the adjacent switch is a load switch, continuously searching the next adjacent switch in the upstream direction, and repeating the step 2.3 and the step 2.4 until the overcurrent breaker is found, and executing tripping operation on the overcurrent breaker.

Fig. 4 is a flowchart of a method for detecting an overcurrent breaker in the power distribution network adaptive differential protection self-healing method based on wireless communication according to the present invention. Generally, in order to reduce the investment cost of primary equipment in a power distribution network, an operation mode in which a circuit breaker and a load switch are used in a mixed manner is generally adopted in the power distribution network. Therefore, in the process of detecting the overcurrent switch and realizing fault isolation, the type of the overcurrent switch should be judged. The specific judgment process is as in step 2.1 to step 2.4.

And 3, after the fault isolation is completed, transmitting a remote signal to the downstream side by the downstream switch of the fault point, and selecting an optimal load transfer scheme based on the data of the interconnection switch and the self-healing strategy.

Preferably, step 3 further comprises: after fault isolation is realized, a fault point downstream switch sends a remote signaling of successful isolation to the downstream; after all tie switches positioned on the downstream side of the downstream switch of the fault point receive the remote signals of successful isolation, the opposite-side indexes of the tie switches are transmitted back to the downstream switch of the fault point; and the downstream switch of the fault point selects the opposite-side indexes returned by all the interconnection switches based on a self-healing strategy so as to obtain the optimal interconnection switch.

Preferably, the interconnection switch is configured to transmit the power supply remaining capacity value data to the opposite side after receiving the power supply information of the one side. Specifically, each time the interconnection switch receives power supply information from one side, the interconnection switch immediately transmits power supply effective remote signaling to the opposite side, and the power supply effective remote signaling is transmitted to the power supply point outgoing switch or another interconnection switch and then stops transmitting, so that each switch knows that the downstream side has a plurality of effective interconnections.

Fig. 5 is a schematic diagram of a judgment logic of a tie switch in the self-healing method for self-adaptive differential protection of a power distribution network based on wireless communication according to the present invention. As shown in fig. 5, in order to obtain data for tie switches, it is first determined which switches in the distribution network are tie switches. In an embodiment of the invention, whether the communication of the current switch is normal, the on-off condition of the switch and the voltage conditions of the power supply side and the load side can be judged within the default 2s time, so that the current switch is confirmed to be the interconnection switch. If the current switch is in an unlocked state, the switch is in a position division position, and the power supply side and the load side are continuously pressed within 2s, the current switch can be determined as a communication switch.

Preferably, the contralateral criteria of the tie switch include: the value of the remaining capacity of the side power supply, the switching priority of the interconnection switch and the recovery delay time. That is, in the self-healing strategy, the interconnection switch with the higher value of the residual capacity of the side power supply is preferentially selected to carry out the power transfer, the interconnection switch with the higher priority in the pre-ranking is preferentially selected to carry out the power transfer, and the interconnection switch with the short recovery delay time is preferentially selected to carry out the power transfer. The three-point information can be comprehensively utilized as self-healing parameters to realize self-healing of the power distribution network according to different application scenes.

Fig. 6 is a logic diagram of transfer power supply in the power distribution network adaptive differential protection self-healing method based on wireless communication according to the present invention. As shown in fig. 6, the load transfer scheme may be implemented according to the acquisition of the contact switch data and the selection of the optimal contact switch.

Preferably, step 3 further comprises: the downstream switch of the fault point generates an optimal load transfer scheme based on the optimal interconnection switch; and the downstream switch of the fault point sends the optimal load transfer scheme to the related interconnection switch, and the related interconnection switch executes closing operation according to the scheme after receiving the load transfer scheme.

As shown in fig. 6, in the present invention, it is necessary to first confirm that the present switch is in "tie switch mode" and the communication is normal, and the switch on the left side and the switch on the right side do not detect a fault; secondly, ensuring that one side of the two sides of the switch is in a pressure state and one side of the switch is in a non-pressure state, namely ensuring that the power supply side is in pressure and the load side is not in pressure or the power supply side is not in pressure and the load side is in pressure; and under the condition of meeting the two points, the switch receives a residual capacity value sent by a power supply point to meet the load transfer demand, and after receiving an isolation success signal, the switch enters switch-on delay, if the switch state is detected to be in an on position after the delay, the power transfer success is indicated, and if the switch state is detected to be in an off position after the delay, the power transfer failure is indicated. The above is the logic of the transfer power in the present invention.

Preferably, the intelligent distributed platform further comprises a power distribution automation master station system, and the power distribution automation master station system is used for regularly detecting system topology changes and generating an SCD file; wherein, the system topology change is caused by the intelligent distributed platform executing the load transfer scheme.

Specifically, in the intelligent distributed platform, fault location and isolation technology is realized between interval layer terminals through a distributed differential protection technology based on peer-to-peer communication, and publication and subscription between adjacent terminals depend on a topological structure. Because the transformation of the power distribution network is frequent, the topology change is inevitable, and in order to reduce the workload of on-site operation and maintenance debugging, configuration change and upgrading procedures, the existing ring main unit or the terminal device of the power distribution room can be intelligently and automatically upgraded, so that the automation of the terminal layer is realized.

Fig. 7 is a schematic diagram of a topology adaptive interface of a distribution network master station in the self-healing method for self-adaptive differential protection of a distribution network based on wireless communication. As shown in fig. 7, according to the adaptive interface of the distribution network master station, the protection adaptive control function of the distribution network mop change can be realized. The master station can be used for realizing functions of protection locking, SCD file issuing, protection activation and the like, and can realize functions of topology self-adaptive analysis, topology refreshing display, SCD display, operation log display and the like.

In particular the distribution network master station may periodically detect changes in the topology of the system. When the master station detects a topology change of the system, a file describing a static connection relationship between switches may be generated by using a series of techniques such as tracking, extracting, and converting, where the file may be an SCD (Substation Configuration Description) file of the IEC61850 standard. And a dispatcher of a workstation in the master station system can send a differential protection command of the intelligent protection terminal affected by the locking based on the webservice according to the judgment, then sends a file, and sends a differential protection command for activating the intelligent protection terminal after the feedback is successful. And after receiving the SCD file, the intelligent protection terminal adaptively updates the GOOSE and SV configuration files for distributed differential protection.

Preferably, the SCD file is used for adaptively updating GOOSE and SV configuration files in a DTU of the intelligent distributed terminal in the intelligent distributed platform; the GOOSE and SV configuration files are used for configuring the collected data of the intelligent distributed terminal DTU into differential protection data for transmission, or for analyzing the received differential protection data from other intelligent distributed terminals DTUs.

Fig. 8 is a schematic network topology diagram of an intelligent distributed platform in an embodiment of a self-healing method for self-adaptive differential protection of a power distribution network based on wireless communication. As shown in FIG. 8, an embodiment is selected in the invention to verify the method in the invention. In the embodiment, a Shenzhen power distribution network 5G differential protection demonstration project is selected. In the project, 2 in-station 10kV feeders and 4 out-station ring main units are covered. Wherein 2 10kV feeders in the station are 110kV positive hole station and 110kV post head station respectively, and 4 out-of-station ring main units are respectively Corona ring net cage, rural area ring net cage, Highui ring net cage and positive sea ring net cage. A set of 5G differential protection terminal and 5G CPE are configured on the in-station outgoing switch, the ring main unit of the station is at 4 intervals, and a DTU (digital television Unit) containing 5G differential protection and the 5G CPE are respectively installed in the protection screen. The 5G communication provides accurate time service for the DTU terminal integrating differential protection, the time service precision is less than 1 mu s, three-remote automatic service and differential protection service are simultaneously borne through a slicing technology, the transmission delay is less than 15ms, and the related delay characteristic, bandwidth capacity and transmission reliability meet the requirements of distribution network wireless differential protection service.

Table 1 is a table of the differential protection service test results in the examples. As shown in Table 1, the results of the test items are passed and verified.

Table 1 table of differential protection service test results in the embodiment

Compared with the prior art, the self-healing method for the self-adaptive differential protection of the power distribution network based on the wireless communication has the beneficial effects that the monitoring control of the running state of the power distribution network and the rapid positioning, isolation and recovery of the fault of the power distribution network can be realized. Compared with the prior art, the scheme provided by the invention has the advantages of high reliability and low cost.

The beneficial effects of the invention also include:

1. the problem of frequent transformation of the power distribution network in the prior art is solved, and the workload of operation and maintenance debugging is greatly reduced by adaptively adjusting the topological model and the relevant parameters in the model;

2. the power supply recovery of a millisecond-level non-fault area is realized by utilizing a distributed self-healing technology, and the power failure time is shortened;

3. the sampling point interpolation synchronization technology based on global time synchronization is utilized to realize accurate positioning of the power distribution network fault in an unstable communication environment; meanwhile, reliable fault location within 70ms of the power distribution network is achieved by utilizing a 5G communication network environment with large bandwidth.

The present applicant has described and illustrated embodiments of the present invention in detail with reference to the accompanying drawings, but it should be understood by those skilled in the art that the above embodiments are merely preferred embodiments of the present invention, and the detailed description is only for the purpose of helping the reader to better understand the spirit of the present invention, and not for limiting the scope of the present invention, and on the contrary, any improvement or modification made based on the spirit of the present invention should fall within the scope of the present invention.