Impacts of space and surface memory effects on streamer dynamics and flashover characteristics under repetitive submicrosecond pulses in nitrogen

Abstract

Decrease in surface insulation capability under repetitive pulses significantly hinder the further enhancement of discharge physics effects, however, fundamental mechanisms of surface flashover under repetitive pulses remain unclear. Developing characteristics of surface streamer and influential mechanisms of memory effects under repetitive submicrosecond pulses were investigated. Both the inception moment and the propagation velocity of subsequent positive surface streamers decrease with increasing the pulse repetition frequency. Enveloping curves of the number of pulses before flashover are similar to the gas gap breakdown. Impacts of space and surface memory effects on the inception and propagation of surface streamers are discussed for repetitive submicrosecond pulses and high-pressure nitrogen.