Partial Discharge Localization in Insulation Oil by Electrical-Acoustic Method

This paper presented a partial discharge (PD) localization in insulation oil by an electrical-acoustic method, which is suggested as an implement for online condition monitoring of oil-immersed power transformers. A needle-plane electrode was fabricated to simulate a PD defect in transformer oil. The pulse signal of electrical current was detected by high frequency current transformer (HFCT) while three acoustic emission (AE) sensors were attached at the outside of the tank wall to detect AE signals. The signals were synchronously acquired by two NI scopes (USB-5133, 100MS/s ) triggered by a pulse generator. The peak detection method based on the threshold value as well as the energy criterion (EC) method determined by signal energy and a negative trend were applied to estimate the arrival…