New Partial Discharge location method in power transformer based on acoustic wave propagation characteristics using numerical simulation

Acoustic Partial Discharge (PD) detection method is useful tool to locate PD source in oil-filled transformers. We have studied acoustic wave propagation characteristics, to improve the diagnostic technique for electric power transformer. This paper also reports on new PD location method with considering oil-filled transformer internal structure by numerical simulation of acoustic wave propagation using finite element method. The numerical simulation was carried out for an actual transformer model in which a PD source was set between windings, iron core and a tank. Calculated acoustic signals were examined in time-frequency domain using the wavelet transform analysis. From these results, enhancement of identification precision of PD source location was discussed.