A method for remote tripping of transmission lines

Abstract

The invention relates to a remote tripping method of an electric transmission line. The method comprises the steps that first, when a dead zone fault happens, a busbar differential protection device acts to send busbar differential protection action input signals to a circuit protection sub device on one side; second, after the circuit protection sub device receives the busbar differential protection action input signals, the circuit protection sub device makes current signals formed by current signals on the side of the circuit protection sub device after reversed polarity to be involved in differential element action judgment calculation, and then sends the current signals formed by the current signals on the side of the circuit protection sub device after reversed polarity to a circuit protection sub device on the other side; third, the circuit protection sub devices conduct differential protection action to achieve remote tripping. The remote tripping method of the electric transmission line can stably and reliably achieve tripping protection when the dead zone fault happens, simplify the protection device, and have high sensitivity and reliability.

Description

technical field [0001] The invention relates to a remote tripping method used in power transmission lines. Background technique [0002] In order to ensure the safe and stable operation of the power system, we hope that after any point in the system fails, the protection device can remove the fault as quickly as possible, especially in the power grid of 220kV and above, this performance requirement is particularly important, otherwise it may cause The system oscillates and decouples, leading to large-scale power outages such as grid collapse and disintegration. [0003] See attached figure 1 The transmission line system shown includes a busbar and several A wires connected to the busbar. The protection usually configured in Line A is a longitudinal split-phase current differential protection device, which includes two line protection sub-devices at TA (current transformer) on both sides of Line A, here are the M-side lines protection sub-device and N-side line protection ...

AI Technical Summary

Problems solved by technology

[0020] The above method is widely used in the current split-phase current differential protection, but its main problems are: ① Due to the reliability of the software and hardware of the protection device and channel equipment, the remote trip command is sent by mistake, causing the circuit breaker to trip by mistake Accidents often occur in the system

②In order to prevent false tripping of the circuit breaker caused by sending a remote trip command by mistake, the measures taken on the one hand complicate the encoding of the remote trip command, and the corresponding decoding on the receiving side also becomes complicated; After the remote trip command sent from the opposite side, the local judgment is performed to confirm the reliability of the remote trip command. This requires an external special local judgment device, so the above methods all make the protection principle more complicated.

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