Influence of the Groove on Barrier Surface on Creeping Discharge Characteristics in N2 Gas under µs Pulse Voltage

For a needle-plane electrode system with a barrier, which establishes the electric field across the axis of a groove, creeping discharge characteristics in N₂ gas under µs pulse voltage applications have been investigated. The distance h between the barrier surface and the needle tip as well as the distance M between the groove center and the needle tip were changed. In the case of h=0.3mm, when the needle tip is located near the far-side groove edge from the plane electrode (M=0.6mm), the flashover voltage has the maximum value. At that time, a growth of a corona is suppressed near the groove edge. These unique characteristics should associate with a field relaxation.