Flashover performance of 380 kV V-string with uniform surface pollution

This study presents uniform pollution effects on the flashover/withstand performance of 380 kV V-suspension strings composed of cap-and-pin type glass insulator units. The motivation behind the study is to investigate the reason of unexpected flashover problems in 380 kV National Electric Power Transmission System. Power frequency voltage tests and impulse voltage flashover tests were performed at Fuat Kulunk High Voltage Laboratory of Istanbul Technical University for clean insulators as well as for uniformly polluted ones. Flashover/withstand voltage levels, flashover paths and time-to-flashovers were determined of the clean and polluted insulator strings.