A new wavelet coefficients correlation denoising method applied in fault detection

In fault detection of power system, the detection for mutations signal is very important. The application of wavelet coefficients correlation denoising in signal detection for noisy fault problem is relatively widespread. However, after doing wavelet transform to the noisy signal, the wavelet coefficients of each scale will produce a small offset. This paper presents a wavelet coefficients correlation denoising method based on the cross-correlation function. Cross-correlation algorithm is used to calculate the offset between each scale coefficient and original noisy fault signal. Then do correlation analysis to the shift scale signal to get accurate mutation signal, so as to determine the location of faults.