Effect of Tower Footing Resistance on Back Flashover for A Double Circuit Line

摘要

An investigation is carried out on an EMTP model of a 400kV double circuit line to analyze overvoltages that occur due to a lightning strike on the phase and the ground wire. Lightning strike response corresponding to different front time and the tower footing resistance are analyzed. In this paper, the impact of back-flashover on the overvoltage profile at different points on the tower is also analyzed. It is observed that both tower footing resistance and front-time of lightning surge play a significant role in determining the value of over-voltage.