Suppressing white noise in PD signal based on wavelet entropy and improved threshold function

Aiming at the shortcomings of traditional hard threshold method and soft threshold method, this paper puts forward a wavelet de-noising method based on wavelet entropy and improved threshold function. First, the noisy partial discharge (PD) signals are processed by wavelet decomposition, then the wavelet coefficients are processed by a new improved threshold function using adaptive selection of threshold based on wavelet entropy, finally the denoised signal can be got by reconstruction. The de-noising results of typical simulative signals and the field signals reveal that this present method can remove white noise effectively.