Inference of PD in electrical insulation by charge-height probability distribution. Diagnosis of insulation system degradation

Author

Contin, A. ; Gulski, E. ; Cacciari, M. ; Montanari, G.C.

Author_Institution

Dipt. di Elettrotecnica, Elettronica ed Inf., Trieste Univ., Italy

Volume

5

Issue

1

fYear

1998

fDate

2/1/1998 12:00:00 AM

Firstpage

110

Lastpage

117

Abstract

This paper deals with application of stochastic procedures for the analysis of PDHD (partial discharge height distributions) detected during life of insulation systems. Experiments of accelerated aging under electrical stress were carried out on both an artificial flat cavity and a 23 kV epoxy-resin insulator, where PD are already active at the beginning of aging. A correlation between aging time and PDHD features is observed during long-term voltage application, until breakdown, on both objects. In particular, the PDHD analysis is approached by means of the Weibull function. It is shown that the time evolution of shape and scale parameters can provide diagnostic indications on aging amount, incoming failure and thus on the reliability of insulation systems

Keywords

Weibull distribution; ageing; epoxy insulation; insulation testing; life testing; partial discharges; stochastic processes; 23 kV; PD; PDHD; Weibull function; accelerated aging; artificial flat cavity; breakdown; charge-height probability distribution; degradation diagnosis; electrical insulation; electrical stress; epoxy-resin insulator; failure; life; partial discharge height distribution; reliability; stochastic analysis; Aging; Breakdown voltage; Degradation; Dielectrics and electrical insulation; Partial discharges; Power transformer insulation; Probability distribution; Shape; Stochastic systems; Thermal stresses;

fLanguage

English

Journal_Title

Dielectrics and Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

1070-9878

Type

jour

DOI

10.1109/94.660784

Filename

660784