Lightning Performances for AC 500kV Transmission Lines with Quadruple-Circuit on Single Tower

Lightning stroke fault is one of the most important factors which must be considered when setting transmission lines on high towers. In this paper, some electrical performances for AC 500 kV transmission lines with Quadruple-Circuit on single tower are presented, and lightning performances calculation and analysis are obtained by EMTP (Electromagnetic Transients Program). On the one hand, the impacts of different factors such as impulse ground resistance, etc. on the lightning performances of back flashover are calculated and analyzed in details. Potential waveforms of tower body and cross-arms are presented, as well as voltage waveforms between cross-arms and conductors. On the other hand, lightning performances of shielding failure are studied through changing the mark-height of the tower, shielding angle and other parameters. In the end, measures to improve lightning performance of 500kV AC transmission lines with Quadruple-Circuits are put forward.