Power Quality Analysis And Evaluation System

With the rapid development of society,electric energy has become an indispensable energy,and power quality has gradually become the focus of power users.With the continuous access of various non-linear loads in power grid,power quality problems are increasing day by day,such as harmonics,voltage deviation,voltage fluctuation and flicker,voltage sag and so on,they have a tremendous impact on people's production,life and even the economic and technological development of the country.Therefore,how to reasonably evaluate various power quality indicators and conveniently analyze power quality problems has become an insurmountable issue in the management of power quality problemsFirstly,based on the basic concepts of power quality and related indicators,this paper analyzed the basic situation of power quality research at home and abroad;then developed an analysis and evaluation platform for power quality problems;finally,put forward comprehensive evaluation indicators to reasonably evaluate the overall power quality of power system.The main work is as follows:(1)A power quality monitoring,analysis and evaluation platform is developed.Aiming at the problems of more indicators and cumbersome evaluation in the traditional analysis and evaluation of power quality,a power quality analysis and evaluation platform is established by combining the analysis and evaluation of power quality with software.The platform includes data statistics and analysis,index calculation,cause analysis,hazards and impacts of various indicators in power quality.and is displayed intuitively in various ways.Taking harmonic analysis in steady state index and voltage sag in transient index as examples,the power quality monitoring,analysis and evaluation platform is elaborated in detail,which provides a more convenient way for power quality analysis and evaluation(2)Research on power quality comprehensive evaluation algorithm.According to the principle of short board effect,a comprehensive evaluation method of power quality is studied.Firstly,the algorithm normalizes the evaluation indexes and integrates them into comprehensive indexes by using the short board effect.Secondly,the index requirements of the national power network are scored.The abnormal information of the projection indexes is analyzed by the standard deviation of the projection values and the corresponding evaluation level relationship,and the projection objective function is constructed.Then,the genetic algorithm is used to calculate the maximum of the objective function.The projection direction is regarded as the best projection direction.Finally,the structure chart and the optimal projection value of the comprehensive evaluation level are obtained by using the optimal projection direction,and a multi-level comprehensive evaluation model of power quality is established,which realizes the comprehensive evaluation of various indicators of power quality.