Luminous characteristics of lightning impulse breakdowns in inhomogeneous SF6 gas gap

초록

Abstract In this paper, the V-p characteristics, the V-t characteristics and the discharge luminous events in inhomogeneous SF6gas gap under the positive and negative lightning impulse voltages are presented. The test gap was composed of the plane-to-plane with a needle-shaped protrusion. In a consequence, the dielectric strengths versus time to breakdown of SF6 gas gap under positive lightning impulse voltages were independent of the gas pressure. The branches of discharge channel for the positive polarity were created and thedirections of the discharge paths were random. On the other hands, the discharge paths were more thicker, and brighter,the presence of the negative polarity.