Effect of White Discharge Trace on Impulse Creeping Discharge Characteristics in Oil/Pressboard Composite Insulation System

Abstract

We have investigated the effect of white discharge trace remaining on pressboard (PB) surface on the impulse creeping discharge characteristics in oil/PB composite insulation system. This paper deals with the effect of the white trace on the partial discharge inception voltage (PDIV), the number of discharge pulses, the discharge charge amount, and the time delay of discharge occurrence under the standard lightning impulse voltage application. Then, we also investigated the mechanism how the white trace affected the creeping discharge characteristics.