Role of Dielectrics in Discharge Voltage Decrease

Abstract

A brief review is given on the role of dielectrics in gas discharge processes. Attention is focused on the key features of the charging mechanism of dielectric films on electrode surfaces and the subsequent breakdown of the discharge. It is experimentally shown that the explosion of surface dielectric films plays a decisive role in discharge voltage decrease. This is a direct result of the electric field distortion between the electrodes due to the accumulation of volume charge.

The particularities of spark channel formation in helium gas at atmospheric pressure

“…Under high values of the applied voltage amplitudes U , the results show that there are instabilities in the discharge, and thereby in the rear front of the discharge pulse current one can observe oscillations which, as a rule, serve to constrict the volume discharge. At this moment, the discharge current and the voltage across the gap spacing, after a stepwise duration time, slowly decrease to zero values [24]. When the contraction stage of the volume discharge is established and transformed into a spark channel, the breakdown voltage decreases to zero value.…”