A double-terminal protection method for phase-to-phase faults based on phase-to-phase arc voltage characteristics

Abstract

The invention discloses a line phase-to-phase fault double-end protection method based on phase-to-phase arc light voltage characteristics. Fault phase-to-phase voltages and fault phase-to-phase currents of two ends of a power transmission line are measured first, the fault phase-to-phase voltage of the other end of the power transmission line is calculated by using the fault phase-to-phase voltage and the fault phase-to-phase current of one end of the power transmission line, a power transmission line phase-to-phase arc light voltage is figured out, and then the power transmission line phase-to-phase arc light voltage and a power transmission line rated voltage are utilized to constitute a phase-to-phase high resistance short-circuit fault voltage protection criterion of the power transmission line. In the method, influences of the power transmission line phase-to-phase arc light voltage are taken into consideration in an algorithm model, influences of transition resistance and load currents are eliminated in principle, great capacity for resisting to influences of transition resistance and load currents is achieved, and the method is suitable for relay protection of the whole fault process after a power transmission line phase-to-phase high resistance short-circuit fault occurs. Lumped parameter modeling is adopted in the method, the algorithm principle is simple, the program is easy to implement, the operation amount of algorithm is less, and the protection action speed is high.

Description

technical field [0001] The invention relates to the technical field of electric power system relay protection, in particular to a double-terminal protection method for line-phase faults based on inter-phase arc voltage characteristics. Background technique [0002] Relay protection is the first line of defense to ensure the safe and stable operation of the power grid, and its accurate and fast action is crucial to isolating faults and preventing accidents from spreading. The traditional backup protection is based on local electrical quantities, which need to be coordinated with offline preset values ​​to ensure the selectivity of protection actions. The outstanding problems of this mode are that the protection setting is complex and the action delay is long, which has been difficult to meet the security and stability requirements of modern complex power grids. In the case of large-scale power flow transfer, the remote backup protection is prone to chain malfunctions, which ...

AI Technical Summary

Problems solved by technology

The electrical quantity involved in the calculation of this method is the fault component, which is only applicable to the relay protection within two weeks after the fault of the transmission line; the operation performance of this method is seriously affected by the transition resistance, and when the high-impedance grounding fault of the transmission line, there will be a situation of refusal , unable to isolate the fault line from the power grid in time; this method is related to the system impedance parameters, and is affected by the system operation mode in principle

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