PD pattern analysis during induced test of large power transformers

The partial discharge (PD) measurements on power transformers are studied with a view toward discrimination and classification of different discharge sources. For this purpose digital analysis is applied to power transformers and reactors going through acceptance testing. Furthermore, based on these measurements, PD databases have been developed to support the discharge evaluation during induced voltage tests of transformers. Using this technique, a clear distinction is possible between transformers showing different discharge behavior.