Analysis on Mal-action of Mal-function Protection and the Countermeasure of 220 kV substation in Licheng

Focusing on an incorrect operation of 220kV circuit-breaker failure protection in Licheng substation,this paper analyzes its causes in-depth.Based on upgrading the reliability and normalization of circuit-breaker failure protection,some measures of configuration,grouped screens,circuits are given for new construction,reconstruction and expansion of substations.For the circuits in-service of circuit-breaker failure protection,this paper puts forward a "point by point measurement of voltage" test method which can ensure the credibility of test results.Practical operation and fault analysis verify the correctness and effectiveness of the measures.