Analyzing partial discharge pulse sequences-a new approach to investigate degradation phenomena

This paper presents a new method of partial discharge data analysis for the investigation of space charge and degradation phenomena in high voltage insulation systems. The basic principles of the pulse-sequence-analysis are illustrated and the characteristic differences with regard to standard procedures that have been established during the past few years are outlined. A description is given of an electronic partial discharge acquisition system, which is designed on a plug-in interface board for a standard personal computer to perform long term measurements of all the discharge parameters required for the succeeding PSA. Electrical treeing in polyethylene is used to demonstrate the usefulness of the PSA method. It is shown that information on space charge phenomena and the development of the local degradation can be obtained by considering correlations between consecutive discharge pulses