Endurance of electrical insulation under non-sinusoidal voltage stress

This paper will discuss the manner in which the number of partial discharges per cycle in a single insulation void depends on the applied voltage for any periodic waveshape, including sinusoidal, in which only one positive and one negative peak per cycle occur, and will then describe the effect of intermediate peaks during the cycle. Finally, a general procedure will be suggested for estimating conservatively the relative endurances of insulation subjected to an arbitrary periodic voltage wave, compared to a sine wave of the same peak-to-peak magnitude. We assume that the insulation is electrically loss-free.