Application of new wavelet threshold in signal-denoise for variable frequency and speed regulation system

Abstract：Based on the wavelet threshold de-noising method analysis which put forward by D.L.Donoho and I.M.Johnstone, four familiar getting threshold methods of the wavelet de-noising, which are sqtwolog, rigrsure, heursure and minimaxi, are compared.A new kind of threshold to de-nosing, which is a novel energy cell based wavelet threshold de-noising method is presented.Through numerical simulation of MATLAB, new threshold value law can strain noise and useless high-frequency weight of signal throughly, possible reduction low frequency and loss of useful high-frequency information.Numerical simulations show that this de-noising method is effective and excellent.

Keyword：variable frequency speed regulation;threshold function;wavelet transform;fault diagnosis;