This paper makes statistic of the lightning faultily tripping of Anhui 220kV transmission lines and analyzes the reason of faultily tripping,also it puts forward the rationalization suggestion for operating and maintenance of transmission lines.

Because of the frequent trip failures on the traction DC switch of TPS(traction power supply)and the high speed switch of train in Shanghai Metro,this paper concludes that the continued overload is the major reason for trip failure,explains other discrete phenomena.

Analysis of the tripping of the circuit breaker by the AC in the DC;