CN107611939A - A kind of block supply ring network fault quickly isolates and load transfer method - Google Patents

Abstract

The invention discloses a method for rapid fault isolation and load transfer of a regional power supply ring network. Through the high-speed communication network, the current sampling value, switch state, and remote control information of the node are sent to the adjacent power supply node, and the current sampling value, switch state, and remote control information sent by the adjacent node are accepted at the same time. The present invention can be used for regional power supply Network, independent of the main station system, can automatically complete fault isolation and power supply restoration in non-faulty areas, minimize the scope of fault power outages, shorten the power outage time in non-faulty areas, and improve power supply reliability.

Description

A fast fault isolation and load transfer method for regional power supply ring network

technical field

The invention relates to the field of electric power system automation, in particular to a method for rapid fault isolation and load transfer of a regional power supply ring network.

Background technique

In order to improve the reliability of regional power supply, the power distribution network is now promoting the ring network power supply mode. Due to the short distance of the lines in the distribution network, the conventional overcurrent protection has a fixed value and a time limit that is difficult to set, and cannot meet the basic requirements of relay protection. At present, the domestic power distribution automation mostly adopts the recloser/sectioner method, the communication-based feeder automation method, etc. The recloser/sectioner method uses the circuit breaker as the trip switch, and determines the fault area by reclosing the circuit breaker and load switch multiple times, which requires multiple trip switches, resulting in large switching losses and long power outages. The protection function of the communication-based feeder automation mode is completely dependent on the master station, and the fault location takes a long time. After the fault, the entire line will be cut off for a short time. The above methods no longer meet the requirements of users, especially important loads, for high reliability of power supply.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for rapid fault isolation and load transfer of a regional power supply ring network, so as to solve the problems mentioned in the background technology.

To achieve the above object, the present invention provides the following technical solutions:

A method for rapid fault isolation and load transfer of a regional power supply ring network, comprising the following steps:

A. The smart terminal collects the current and voltage data of the nodes in this interval in real time, the switching status of each switch and the topology information of the power supply network;

B. Through the high-speed communication network, send the current sampling value, switch status, and remote control information of the node to the adjacent power supply node, and at the same time accept the current sampling value, switch status, and remote control information sent by the adjacent node;

C. According to the protection logic set by the system combined with the real-time data of each node, in the event of a fault, according to the protection logic configured by the system, the fault type and fault area can be quickly judged;

D. Start the trip program according to the fault area, trip the corresponding switch, and isolate the fault;

E. After the fault is isolated, the node switch in the area is disconnected and sends a remote closing command to the communication network. After receiving the remote closing command, the normally open node of the power supply ring network starts the closing procedure, closes the normally open switch, completes load transfer, and restores Power supply for non-faulty areas.

As a preferred solution of the present invention: the specific method of step 2: the intelligent terminals of each node are connected hand in hand through optical cables or twisted pairs; each node only exchanges data with upstream and downstream adjacent nodes, and transmits analog data , switch status, remote control information; data is sent at fixed time intervals, works in full-duplex mode, data transmission is verified and responded, and the alarm program is started for multiple consecutive verification errors or no response.

As a preferred solution of the present invention: the specific method of the step 3 is: each node calculates the fault current according to its own sampling value and receiving the sampling value of the adjacent node, with the differential quick-break as the main protection, and the overcurrent direction protection as the backup protection, Determine the fault type and fault area.

As a preferred solution of the present invention: the specific method of step 4 is: after the power supply ring network fails, the intelligent terminal of the corresponding regional node will start the trip program, drive the circuit breaker to trip, and send the opposite side trip command at the same time, so that the other side of the faulty region The intelligent terminal on the side starts the trip program to trip the corresponding circuit breaker on the opposite side to isolate the fault.

As a preferred solution of the present invention: the specific method of the step 4 is: after the fault isolation, the intelligent terminal of the node in the fault area detects the position of the circuit breaker, and when the switch sends a remote closing command to the communication network after the switch is divided, the communication network According to the topological structure of the power supply ring network and the position of the normally open switch in the node, each node starts the closing procedure of the corresponding node switch, closes the normally open switch, completes the load transfer, and restores the power supply in the non-faulty area.

As a preferred solution of the present invention: the intelligent terminal includes an analog quantity acquisition module and a switch quantity acquisition module, an export drive module, a communication module and a data processing module; the intelligent terminal collects the current and voltage analog quantity data of the node entering and leaving the ring network in real time , The switch's tripping state.

Compared with the prior art, the beneficial effects of the present invention are: the present invention can be used in regional power supply networks without relying on the main station system, can automatically complete fault isolation and power supply recovery in non-faulty areas, minimize the scope of fault power outages, and non-faulty areas Short power outage time improves power supply reliability.

Description of drawings

Fig. 1 is the system structural diagram of fast fault isolation and load transfer of regional power supply ring network of the present invention;

Fig. 2 is a schematic diagram of a power supply failure and its processing according to an example of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Figure 1-2, a method for rapid fault isolation and load transfer of a regional power supply ring network, including the following steps:

A. The smart terminal collects the current and voltage data of the nodes in this interval in real time, the switching status of each switch and the topology information of the power supply network;

B. Through the high-speed communication network, send the current sampling value, switch status, and remote control information of the node to the adjacent power supply node, and at the same time accept the current sampling value, switch status, and remote control information sent by the adjacent node;

C. According to the protection logic set by the system combined with the real-time data of each node, in the event of a fault, according to the protection logic configured by the system, the fault type and fault area can be quickly judged;

D. Start the trip program according to the fault area, trip the corresponding switch, and isolate the fault;

E. After the fault is isolated, the node switch in the area is disconnected and sends a remote closing command to the communication network. After receiving the remote closing command, the normally open node of the power supply ring network starts the closing procedure, closes the normally open switch, completes load transfer, and restores Power supply for non-faulty areas.

Step 2 Specific method: The intelligent terminals of each node are connected hand in hand through optical cables or twisted pairs; each node only exchanges data with upstream and downstream adjacent nodes, and transmits analog data, switch status, and remote control information; data Send at fixed time intervals, work in full-duplex mode, check and respond to data transmission, and start the alarm program if there are multiple consecutive check errors or no response.

The specific method of step 3 is: each node calculates the fault current according to its own sampling value and the sampling value received from adjacent nodes, the differential quick-break is the main protection, the overcurrent direction protection is the backup protection, and the fault type and fault area are judged.

The specific method of step 4 is: after the power supply ring network fails, the intelligent terminal of the corresponding area node will start the trip program, drive the circuit breaker to trip, and send the opposite side trip command at the same time, let the intelligent terminal on the other side of the fault area start the trip program to trip Corresponding opposite side circuit breaker, isolate the fault.

The specific method of step 4 is: after the fault is isolated, the intelligent terminal of the node in the fault area detects the position of the circuit breaker. Combined with the position of the normally open switch in the node, start the closing procedure of the corresponding node switch, close the normally open switch, complete the load transfer, and restore the power supply in the non-faulty area.

The intelligent terminal includes an analog quantity acquisition module and a switch quantity acquisition module, an export drive module, a communication module and a data processing module; the intelligent terminal collects the current and voltage analog quantity data of the node entering and leaving the ring network in real time, and the switching state of the switch.

The working principle of the present invention is: FIG. 2 is a schematic diagram of fault isolation and load transfer of the protection system of the present invention. First, each node collects the current and voltage data of the interval node in real time, the switch state of each switch and the topology information of the power supply network;

Then through the high-speed communication network, send the current sampling value, switch status, and remote control information of the node to the adjacent power supply node, and at the same time accept the current sampling value, switch status, and remote control information sent by the adjacent node;

According to the protection logic set by the system combined with the real-time data of each node, when a fault occurs on the line D in Figure 2, the system makes a differential |I1-I2|> differential determination based on the current values of #N nodes and #(N-1) nodes When the value is set to start tripping, #N node circuit breaker QF2 trips, and #N node sends the opposite side trip command and remote closing command to #(N-1) node at the same time, after multiple confirmations #(N-1) node circuit breaker QF1 trips and isolates the D-section line. When it is detected that the #(N-1) node circuit breaker QF1 is tripped, execute the remote closing command, close the #(N-1) node normally open circuit breaker QF2, and the incoming line 2 Supply power to #(N-1) node outgoing loads. The current differential protection action time is less than 40ms, the fault isolation time is less than 90ms (including the circuit breaker opening time of 50ms); the system startup closing action time is less than 90ms (including the circuit breaker closing time of 80ms), the overall time of fault isolation + load transfer Less than 180ms.

In Figure 2, when the fault B occurred on the #2 node bus, the overcurrent direction protection was activated, and it was judged that the fault occurred on the bus side, and the tripping program was started to trip the #2 node circuit breaker QF1, QF2 at the same time, isolating the #2 node bus, and the system detected After the circuit breaker opens the position, send the remote closing command to the adjacent #1 node and #3 node. After receiving the remote closing command, each node will confirm the position of the normally open circuit breaker according to the topology of the ring network after multiple confirmations. As shown in the #(N-1) node circuit breaker QF2 in Figure 2, the #(N-1) node intelligent protection terminal starts the closing procedure, closes the circuit breaker QF2, and the incoming line 2 supplies power to the load behind the #2 node. The current direction protection action time is less than 40ms, the fault isolation time is less than 90ms (including the circuit breaker opening time of 50ms); the system startup closing action time is less than 90ms (including the circuit breaker closing time of 80ms), and the overall time of fault isolation + load transfer is less than 180ms.

After a fault occurs, the system can send fault information to the main station system through multiple communication methods such as wireless, twisted pair or optical cable, and assist the on-duty personnel in monitoring the power supply network and troubleshooting the fault.

The above-mentioned embodiments do not limit the present invention in any form, and all technical solutions obtained in the form of equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims (6)

1. A method for rapid isolation and load transfer of a regional power supply ring network failure, characterized in that it comprises the following steps: A. The smart terminal collects the current and voltage data of the nodes in this interval in real time, the switching status of each switch and the topology information of the power supply network; B. Through the high-speed communication network, send the current sampling value, switch status, and remote control information of the node to the adjacent power supply node, and at the same time accept the current sampling value, switch status, and remote control information sent by the adjacent node; C. According to the protection logic set by the system combined with the real-time data of each node, in the event of a fault, according to the protection logic configured by the system, the fault type and fault area can be quickly judged; D. Start the trip program according to the fault area, trip the corresponding switch, and isolate the fault; E. After the fault is isolated, the node switch in the area is disconnected and sends a remote closing command to the communication network. After receiving the remote closing command, the normally open node of the power supply ring network starts the closing procedure, closes the normally open switch, completes load transfer, and restores Power supply for non-faulty areas. 2. A method for rapid fault isolation and load transfer of a regional power supply ring network according to claim 1, characterized in that, the specific method of step 2: the intelligent terminals of each node are connected hand in hand through optical cables or twisted pairs ;Each node only exchanges data with upstream and downstream adjacent nodes, transmitting analog data, switch status, and remote control information; data is sent at fixed time intervals, works in full-duplex mode, and checks and responds to data transmission. If there are multiple consecutive verification errors or no response, start the alarm program. 3. A method for fast isolation and load transfer of regional power supply ring network faults according to claim 2, characterized in that, the specific method of step 3 is: each node receives the sampled value of the adjacent node according to its own sampled value Calculate the fault current, take the differential quick-break as the main protection, and the over-current direction protection as the backup protection, and judge the fault type and fault area. 4. A method for fast isolation and load transfer of regional power supply ring network faults according to claim 1, characterized in that the specific method of step 4 is: after the power supply ring network fails, the intelligent terminal corresponding to the regional node will start The trip program drives the circuit breaker to trip, and at the same time sends the opposite side trip command, so that the smart terminal on the other side of the fault area starts the trip program to trip the corresponding opposite side circuit breaker to isolate the fault. 5. A method for rapid fault isolation and load transfer of a regional power supply ring network according to claim 1, characterized in that the specific method of step 4 is: after the fault is isolated, the intelligent terminal of the node in the fault area detects the disconnection When the switch is in position, it sends a remote closing command to the communication network, and each node of the communication network starts the closing procedure of the corresponding node switch according to the topological structure of the power supply ring network and the position of the normally open switch in the node, and closes the normally open switch. Turn on the switch to complete the load transfer and restore the power supply in the non-faulty area. 6. A kind of regional power supply ring network fault quick isolation and load transfer system according to claim 1, is characterized in that, described intelligent terminal comprises analog quantity acquisition module and switch quantity acquisition module, export drive module, communication module and data Processing module: the intelligent terminal collects the current and voltage analog data of the node entering and exiting the ring network in real time, and the switching state of the switch.