Building a Transformer Defects Database for UHF Partial Discharge Diagnostics

In the case of a defective transformer, when a partial discharge is detected and recorded, critical information can be deduced from its pattern, such as the type of defect, its criticality or even information on the level of degradation of the insulation. This information can help to determine the remaining life of the transformer and thus provide criteria for its maintenance and operation. In this paper different artificial PD patterns will be recorded in the laboratory, representative of specific transformer defects, in order to build a database for comparison purposes when measuring on-line. This can greatly improve the recognition and identification of the defect and thus help take some important life assessment conclusions on the transformer.