The effect of the tip curvature on the prebreakdown current pulse relating to the negative streamer inception

In this paper, the relation between the prebreakdown current pulses associated with the negative streamer inception and the tip curvature was investigated in cyclohexane. The ultra wide bandwidth method was used to measure the prebreakdown current pulse under impulse voltage (1.5/540 /spl mu/s) condition, and a high-speed high magnification shadowgraph system was used to observe the streamers. At a tip curvature of 0.5 /spl mu/m, the charge amount of the first current pulse was 0.12-0.45 pC. On the other hand, at a tip curvature of 1.0 /spl mu/m, the range was 0.39-0.92 pC. When the streamer shape was the same at each tip curvature, the range of minimum injected charge amount to form the streamer was similar.