A new approach in PD diagnosis and PD pattern recognition

Digital measuring techniques and a few diagnosis systems have been developed to assist the test engineer. The most common diagnostic tools are two or three dimensional distributions or histograms which exhibit typical patterns of the PD activity. The main disadvantage of all these graphs in PD diagnosis is the integrative effect of the statistics used. In this paper the authors show a graph of Partial Discharge activity without any integrative effect that gains a diagnostic overview of the whole measurement. In this diagram the parameters charge, phase, time and test voltage are included, by this it is possible to summarize all significant information on one computer print. By seeing PD evolution from period to period, visual recognition and expert classification becomes practicable. Results of acoustical PD classification will be presented and the influence of test voltage on electrical and acoustical PD-recognition is discussed