Research of reclosing failure of transmission lines caused by multiple lightning strikes

Lightning faults of transmission lines are usually instantaneous faults, and most of them can automatically reclose successfully, but reclosing failure will also occur sometimes. The present paper analyses a reclosing failure of a 500kV transmission line after lightning strike. In this paper, the lightning monitoring system is used to monitor power frequency fault current and lightning transient traveling wave current, and the fault location, the cause identification and the reasons for the reclosing failure are obtained based on the monitoring data. The results show that there are several successive lightning strikes near the fault point of transmission line during the switch to closing period, which makes the fault frequency continuous current unable to return to zero, so the insulation cannot be recovered, which ultimately leads to reclosing failure. (paper)