Study on time-frequency characteristic of PD Pulse using Wigner-Ville Distributions

According to the non-stationary of PD pulse signal, the Joint Time-Frequency Analysis (JTFA) is put forward to process the signal to obtain their characteristics in time-frequency domain. At present, the Wigner-Ville Distribution (WVD) which belongs to the Cohen class Time-Frequency Energy Distribution is popular in processing the non-stationary signals. So the simulation PD pulse is chosen as the subject investigated to study on the original WVD, Smoothing-Pseudo WVD (SPWVD) and Rearranged-Smoothing-Pseudo WVD (RSPWVD) in this paper. The results show that WVD provides a high sensitivity to variation in short duration of non-stationary PD signal, which is available to extract the time-varying information. And the SPWVD can remove the interference cross-terms with reducing the time-frequency resolution, which is caused by bilinear function. For having good time-frequency concentration, the RSPWVD provides a powerful tool to evaluate parameters for single PD pulse shape.