Partial Discharges in Transformer Insulation Task Force 15.01.04

摘要

This paper discusses the opportunities for realising thefull potential of modern digital partial discharge detec-torsin the condition monitoring of large oil-filled trans-formers,through the correlation of discharge patternswith typical discharge-inducing defects. The types ofdischarge which can be present in transformers areanalysed and this leads to a discussion on appropriatetest instrumentation to accurately and objectively ac-quire,store and process discharge data. The range ofdischarge-inducing defects to be found in transformersis discussed and this leads into the results of three in-vestigationsby task force members of model geometriesrepresenting such defects variously. In these studiescorrelations were sought among the patterns of dis-chargeactivity and the nature/form of defect model. Onthe basis of these investigations, key parameters areelucidated to include the phase angle of discharge ac-tivity(start, mean and end phase), discharge repetitionrate and discharge magnitude. No evidence has beenfound to support the use of mathematical distributionsof these primary parameters. In addition, from these in-vestigations,the parameters which may influ-ence/control the results obtained (and hence which mustbe controlled) are discussed.