The Research On Lightning-proof Gap For 35kV And 110kV Transmission Line

The aim of this paper is to design a kind of lightning-proof gap, which can be fixed atthe two side of insulator chain. When lightning stroke happened in transmission line, thegap could lead the lightning current to earth therefore the insulation chain was notdestroyed by flashover. Working with the auto-reclose circuit breaker, it can maintainthe operation of transmission line. The main content of the paper includes: based on theactual method of insulation coordination, to design a sound arc distance for the gapusing the knowledge of mathematical statistics;to choose the sound gap style bycalculating the voltage distribution of insulator chain with calculating program ANSYS;to validate the protective capability of the lightning-proof gap by lightning impulseexperiment. The experiment results indicate that the gap can discharge before theinsulator chain when lightning stroke happened, therefore the insulator chain isprotected effectively;to calculate the trip-out rate of lightning stroke of 110kVtransmission line with lightning-proof gap, the calculating results indicate that this gaphas little influence on the trip-out rate, therefore it can be used in actual transmissionline.