COMPUTER-AIDED MEASUREMENT OF PARTIAL DISCHARGES IN HV EQUIPMENT

In this paper the previously developed method of partial discharges (PD) recognition is applied to evaluate PD in HV devices. Using conventional discharge detection (bandwidth similar to 400 kHz) the patterns of PD were studied. Satisfactory results in the past, when analyzing discharges in artificial models, have shown that using the shape of phase-position distributions the origin and the type of discharges can be studied. By means of unambiguous statistical operators like skewness, kurtosis, number of peaks etc. quantitative information about the discharge source can be obtained. In the case of an unknown defect a combination of these operators is compared to the same set of operators for a known configuration. In this way a statement can be made on the character of a discharge source. The use of this technique in evaluating different discharges in HV cable and in 400 kV SF6 insulation confirms the usefulness of the new approach.