Electrical breakdown of a dielectric on the voltage pulse trailing edge: Investigation in terms of the incubation time concept

The time effects of electrical breakdown at the leading and trailing edges of a voltage pulse applied to an interelectrode gap are studied. The pulsed dielectric strengths of limestone, sandstone, clay, paraffin, and water are determined experimentally at fixed parameters of the voltage pulse and different lengths of the dielectric-filled interelectrode gap. Experimental data are explained in terms of a structure–time approach based on the incubation time criterion. It is found that breakdown occurs when a sufficient power impulse (electric energy) arises within a characteristic time rather than when the electric field reaches a limit.