Power Quality Comprehensive Evaluation Method Research And System Development

With the rapid development of the national economy, science and technology, theharm of the power quality pollution to each industry is increasingly serious. Thepower quality and its evaluation have become one of the topics which power sectorsand power users are most concerned about. Several indicators and their organicintegration can be used to evaluate power quality, and the comprehensive evaluationcan reflect the overall condition of power quality, thus in favor of establishing a fairand impartial electric power market.This paper summarizes the meaning of power quality and the definitions andstandards of each indicator, and introduces the researches on the evaluation of powerquality at home and abroad. The commonly used methods for the evaluation of powerquality and its characteristics are analyzed and compared.This paper applies matter element analysis theory to the evaluation of powerquality. By using matter element and correlation function theory in Extenics, build thematter element model for the evaluation of power quality. Quantify the relationshipbetween the evaluation interval and the amount to be evaluated so as to make it forman incidence matrix; several methods (analytic hierarchy process, G1method, Delphimethod, Precedence Chart method, Entropy method, etc.) and integrated weightmethod and combining weights method for weighing each indicator of power qualityare determined in this study. A comprehensive evaluation method for power quality,which is to combine the integrated weight method and matter element analysis methodis proposed.Based on the proposed comprehensive method for the evaluation of power quality,apply the power quality parametric test data and other relevant national standards forpower quality; evaluate the actual power quality and analyze the evaluation results.The analysis results show that applying these methods proposed in this paper for thecomprehensive evaluation of power quality can reflect the real condition of the powerquality in power grid. The results of comprehensive evaluation are more objective,accurate and reasonable. Finally, a comprehensive evaluation system for powerquality is developed based on LabVIEW-a virtual instrument development platform.