Denoising Method of a Power Quality Signal Based on Parameter Coordination of Membership Function in Fuzzy Logic Theory

Considering the characteristics of power quality signals and denoising requirements, a denoising method of a power quality signal based on parameter coordination of membership function in fuzzy logic theory is proposed in this paper. First of all, for the signal sequence of power quality, seven masks are designed to make the best use of the signal sequence information. Secondly, based on fuzzy logic theory, the corresponding membership degrees are calculated for these seven masks, and the average value of all points in these masks is used as the input of fuzzy logic theory. Then, according to the membership function of the input and output variable, the boundary parameters are designed harmoniously to obtain the best denoising effect. Finally, based on the experimental simulation results, it is proved that the proposed method can not only smooth the noise well, but also keep the information for the abrupt point in its entirety, which is more suitable for denoising power quality signals compared with the traditional filtering method.