APPLYING CERTAIN OFF-LINE AND ON-LINE DIAGNOSTIC METHODS FOR HYDROGENERATOR PREDICTIVE MAINTENANCE AND REFURBISHMENT STRATEGY

摘要

The generator damage during a routine high potential test in 1994 was a reason to change diagnostic methods applied. The first results of measurements using a modern off-line partial discharge analyser taken on eight big hydrogenerators were very alarming. This and the results of visual inspections were the basis for the decision to start rewinding the generators. During a few years of using modern off-line tests, the experience was gained, that allows to delay the rewinding of next generators using the predictive maintenance and refurbishment strategy. To implement this strategy the applying of modern on-line methods was necessary. The current results, experience and comparison of several diagnostic methods are presented in the paper.