CN106655124A - Failure protection algorithm and apparatus for line circuit breaker - Google Patents

Abstract

A circuit breaker failure protection algorithm: the directional element on the local side or the distance section II acts, the opposite side directional element or the distance section II action passes through AND gate 1, and then acts with the main protection of the line (including current differential, longitudinal distance, and distance Section I protection) signal passes through OR gate 2; the directional element on this side and distance II section protection action signal pass through OR gate 1 as the criterion that the circuit breaker is not disconnected, and its output signal and OR gate 2 output signal pass through AND gate 2, After the time delay Ts1 (the time delay from the protection action to the return time of the exit relay), the other circuit breakers on the bus connected to this line are tripped. The present invention only utilizes the existing protection action information to realize circuit breaker failure protection, requires a small amount of communication data, and guarantees the performance of circuit breaker failure protection to the greatest extent when the network performance of the process layer of the intelligent substation is degraded or even a network storm occurs.

Description

A circuit breaker failure protection algorithm and device

technical field

The invention relates to the field of power grid relay protection, in particular to a circuit breaker failure protection algorithm and device.

Background technique

Line circuit breaker failure protection refers to the technology that when the line fails, the line protection issues a trip command, and the line circuit breaker moves accordingly, so as to minimize the power failure range and quickly cut off other circuit breakers on the bus connected to the line. In the smart substation, the sampling value information, equipment cooperation instructions, and equipment operation command messages are all completed through the process layer network. The SV (sample value) message is stable, but the GOOSE (trip command, etc.) message has a small normal operation flow and a large burst flow, which may form a network storm and greatly reduce communication performance. In order not to reduce the performance of relay protection, it is hoped to adopt a protection scheme with good performance and small amount of communication data. Because the traditional circuit breaker failure protection directly collects the CT current on the line to judge whether the circuit breaker is disconnected, it needs to collect and process CT current information in real time, and the amount of communication data is large.

Contents of the invention

The technical problem to be solved by the present invention is to provide a circuit breaker failure protection algorithm and device, which can ensure good performance of circuit breaker failure protection when only a small amount of communication data is required.

A circuit breaker failure protection algorithm and device wiring diagram are shown in Figure 1. The device collects the internal protection action information of the current side and the opposite side line protection device of all lines in the substation, including the action information of current differential, longitudinal distance, direction element, and distance element. After judging by the circuit breaker failure protection algorithm proposed by the present invention, if it is determined that the circuit breaker on this side is out of order, then jump off other circuit breakers on the bus connected to this line.

As a further preferred implementation manner, a circuit breaker failure protection algorithm is shown in FIG. 2 . Line main protection actions include current differential, longitudinal distance, and distance I section protection. The directional element on this side or the distance section II action, the opposite side directional element or the distance section II action through the AND gate 1, and then the main protection action signal of the line through the OR gate 2. The directional element on this side and the protective action signal of the distance II section pass through the OR gate 1 as the criterion for the circuit breaker not being disconnected, and its output signal and the output signal of the OR gate 2 pass through the AND gate 2, and then delay Ts1 (this delay hides After the time from the overprotection action to the return of the exit relay, take 100ms), the other circuit breakers on the bus connected to this line will be tripped.

The beneficial effects of the present invention are: only using the existing protection action information to realize circuit breaker failure protection requires a small amount of communication data, and can ensure the maximum protection of the circuit breaker when the network performance of the process layer of the intelligent substation is degraded or even a network storm occurs. Failsafe performance.

Description of drawings

The specific embodiment of the present invention will be further described below in conjunction with accompanying drawing:

Fig. 1 is a circuit breaker failure protection algorithm and device wiring diagram of the present invention;

Fig. 2 is a circuit breaker failure protection algorithm and device principle block diagram of the present invention;

Fig. 3 is a schematic diagram of the main wiring of a power grid in a specific calculation example of a circuit breaker failure protection algorithm and device according to the present invention.

detailed description

Referring to Fig. 1, a circuit breaker failure protection algorithm and device collects the internal protection action information of all lines in the substation on the own side and the opposite side line protection device, including current differential, longitudinal distance, direction element, and distance element action information. After judging by the circuit breaker failure protection algorithm using the existing protection action information, if it is determined that the circuit breaker on this side is out of order, then jump off other circuit breakers on the bus connected to this line.

A circuit breaker failure protection algorithm and device principle are shown in Figure 2. The main protection action of the line includes current differential, longitudinal distance, and distance I section protection. It can be determined that a short circuit fault is occurring in this line; , and then through the OR gate 2 with the line main protection action signal. The protective action signal of the directional element and the distance section II on this side passes through OR gate 1 as the criterion for the circuit breaker not being disconnected (because if the circuit breaker is disconnected, there is no current on the CT, the directional element and the distance section II will not act), and the other After the output signal and the output signal of OR gate 2 pass through AND gate 2, and then delay Ts1 (this delay avoids the protection action to the return time of the export relay, take 100ms), then jump off the bus connected to this line other circuit breakers.

Specific calculation example: In the wide-area power grid shown in Figure 3, if the line L2 fails, the main protection of the line will act at this time, or the main protection will refuse to operate but the directional element on the line 2 side or the distance section II will act correctly. After the protection action to the return time of the exit relay, if the fault can still be identified, and at the same time, any element in the direction element or the distance II section continues to act, it can be judged that the circuit breaker on this side has failed, and the circuit breaker connected to the L2 line can be tripped. Other circuit breakers on connected busbars.

The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the described embodiments, and those skilled in the art can also make various equivalent deformations or replacements without violating the spirit of the present invention. , these equivalent modifications or replacements are all within the scope defined by the claims of the present application.

Claims (2)

1. A line circuit breaker failure protection algorithm and device, characterized in that it includes: collecting the protection action information inside the protection device of the current side and the opposite side of all lines in the substation, including current differential, longitudinal distance, direction The action information of the element and distance element is judged by the circuit breaker failure protection algorithm using the existing protection action information. If it is determined that the line circuit breaker on this side is out of order, it will jump off other open circuits on the bus connected to this line. device. 2. A circuit breaker failure protection algorithm and the circuit breaker failure algorithm adopted by the device according to claim 1, characterized in that: the direction element on the side or the action of the distance II section, and the action of the opposite side direction element or the distance II section AND gate 1, and then AND line main protection action (including current differential, longitudinal distance, distance I section protection) signal through OR gate 2; direction element on this side, distance II section protection action signal through OR gate 1 as a circuit breaker If the criterion is not disconnected, its output signal and the output signal of OR gate 2 pass through AND gate 2, and then delay Ts1 (this delay avoids the protection action to the return time of the exit relay), then jumps to connect with this line other circuit breakers on the bus.