Power transformer PD sources determination using current signals waveshape and pattern distributions

An experimental investigation into the behaviour of partial discharges (PD) in three different types of defect PD models was carried out to study the characterization features. They include corona and discharge along the outer and inner surface of transformers bushing. The signals were collected by a wideband (WB) PD measurement system. Analyses of the signals indicate that the type of PD source can be determined using the signals shape and the PD pattern.