Comprehensive Evaluation of Power Quality Based on Category-Combination Weighting and Blind Number Measure

In the context of power market reform, the comprehensive evaluation of power quality is extremely important for the effective governance of power grids and the reasonable formulation of power prices. The paper proposed a method based on classification combined weighting and for the first time integrated with blind number measurement in order to solve the problems of strong subjectivity, inaccurate results and complex methods in comprehensive power quality evaluation. In the weights section, the subjective weights were calculated by combining load classification and an improved analytic hierarchy process. Then, the objective weights were calculated by the modified entropy weighting method. Finally, the combined weights were obtained by the Lagrange multiplier method. The introduction of load classification enabled the whole method to be more objective. In the evaluation part of the model, blind number theory was applied to modify the data reducing errors caused by data fluctuations. This was followed by a measurement using a curvilinear uncertain function to better distinguish between similar evaluation points. Once the measurements were completed, evaluation grades and scores were obtained. The correctness, objectivity and accuracy of the method were verified by analysis and comparison of practical examples.