To understand the information of partial discharge（PD）and the influence of transformer winding on PD signal propagation

two defect models of suspended discharge and point discharge are built in a 35 kV transformer.The signal at each detection point is measured based on the wide bandwidth pulse current method

and the character-istics of PD signals in different types and at different positions are analyzed. Result shows that: the signal waveformsof different defects are similar but their statistical characteristics are different;the signal from the bushing tap has amore significant change compared with the signals from the core and the neutral point of the winding when PD occurs in different phases;and the winding has a"frequency selection"effect for PD signal.