Study of Partial Discharge Measurement in Power Equipment Using Acoustic Technique and Wavelet Transform

This study proposes a noncontact type of acoustic measurement system and applies wavelet transform to noise suppression in order to raise the correct partial discharge (PD) signal identification rate. We first investigate an acoustic measurement method in the laboratory and apply the wavelet transform to suppress noise. A wavelet mother function most similar to the acoustic PD signals is chosen to set the filtering threshold value for the wavelet transform. Finally, the proposed acoustic measurement system is applied on line to epoxy-resin transformers, power distributors and the like. The superior measurement results we obtained will be able to help maintenance personnel eliminate field noise to correctly identify the PD fault types of power equipment.