Statistical behaviour of internal partial discharges at DC voltage

Abstract

In this paper the relation between successive partial discharges in insulating materials at DC voltage is discussed. Based on a few assumptions a DC voltage model, based on an RC-circuit, is presented and experimentally verified. Measurements of partial discharges have been made on samples containing air filled voids. For discharges of a small magnitude the model proved to be valid. Based on the model the characteristic discharge parameter mean time lag t, and mean recovery time t, have been obtained. For discharges of larger magnitude, the model is not valid. This is probably due to a different discharge mechanism, the 'streamer like' mechanism. Therefore the model could possibly be used for a recognition of the dominant discharge mechanism.<>