The Leader Development and its Mechanism in Air under Impulse Voltage

Abstract

In this paper, the breakdown phenomena in air for both short and long gaps of 3～20 cm length were observed by means of the voltage, current, light pulse measurement and the still photograph observation (accompanied with chopped voltage). Also, the role played by primary and secondary streamers for leader inception and its development are studied. As a result, several delayed streamers which were named here, and which were made of sets of primary and secondary streamers, were observed ; and only when the current pulse of a delayed streamer continues without interruption, the leader occurred.