The Study of SymlestN Wavelet-based Denoising Technology in the test system of transient power quality

At first, discussed the necessity to reduce noise of the electric signals that be measured in the test system of transient power quality, then several kinds of methods of noise reduction be compared in this paper, and finally the wavelet threshold denoising method be selected based on the compared results and the non stationary characteristic of power quality. Then the wavelet base function be constructed, and as key point, the method to select the threshold be analysed at the same time of the rational wavelet decomposition level be determined. At last, to simulate the effect of wavelet threshold denoising method by matlab; as the result, the denoising problem be solved effective through the method above, and it would never generated the distortion that caused by the signal singularity be effected.