AN APPROACH TO PARTIAL-DISCHARGE INVESTIGATION BY HEIGHT-DISTRIBUTIONANALYSIS

Results of partial-discharge measurements, performed on insulation sys tems of rotating machines, are processed referring to the Weibull stat istics. It is shown that the partial-discharge height distribution fit the two-parameter Weibull function when partial discharges having the same origin occur, whereas deviations from the Weibull plot are detec ted in the presence of various simultaneous partial-discharge phenomen a. Probability functions based on the multiplicatively-mixed Weibull d istribution are used to fit data obtained in the presence of partial-d ischarge phenomena of two different types. The shape and the scale par ameters of the Weibull functions derived as functions of test voltage and aging time prove to be characteristics of this kind of phenomenon. Pattern identification and clustering is thus achieved.