Pulse-sequence-analysis-chances to characterize defects

Abstract

Partial discharge data are often used to get information about the ageing situation of high voltage equipment. Local defects generate characteristic sequences of partial discharges that also contain information about the critical regions in which the partial discharges occur. This information can be drawn efficiently from the sequence of the partial discharge events and especially the analysis of the sequence of the changes of the applied external voltage that are necessary to trigger the next discharge event. By means of the Pulse-Sequence-Analysis (PSA) more meaningful results can be drawn than from the commonly used phase-correlated collection and evaluation of partial discharge data. With regard to the total number of registered and evaluated discharge events, data collected from various defects in high voltage equipment show that the analysis of short homogeneous sequences is more meaningful than the analysis of the sequence of e.g. 5000 partial discharge events as a whole.