Flashover characteristics of spacer in SF6 underoscillating and non-oscillating impulses

This paper describes the flashover characteristics and discharge development mechanism on the surface of spacer in SF₆ gas stressed by oscillating and nonoscillating impulses in an inhomogeneous electric field. It is shown that the flashover voltage-time (V-t) characteristics are more dependent on oscillation frequency and rise time of impulses. The pre-discharge current is also detected with a shunt of 50 Ω. It can be seen that the reduction in flashover voltage under fast oscillating impulses may be attributed to the back discharge due to the effect of surface charges