A Fuzzy Comprehensive Evaluation Model of Power Quality Based on Normal Cloud Model

Abstract

Objective and accurate comprehensive evaluation on power quality is an important evidence for power pricing and power quality assessment. Considering the shortcomings existing in the current methods, a fuzzy comprehensive evaluation model of power quality based on normal cloud model is proposed. The normal cloud model is introduced to improve the membership function, and the normal cloud models on grade demarcation of power quality are established so that the fuzzy relation matrix is obtained. Entropy weight method is used to determine the weight of the evaluation indicators. In order to get the comprehensive evaluation grade of power quality, the unsymmetrical proximity criterion is used to analyze the fuzzy comprehensive vector which calculated by weight matrix and the fuzzy relation matrix. Finally, the accuracy and effectiveness of the proposed method are verified by a practical example.