Comprehensive Evaluation Of Harmonics Management For Power Consumers

With the rapid development of the power system,the number of the non-linear loads has been largely increased,which makes harmonic issue faced by the power consumers more and more serious.How to suppress the harmonic issue effectively and economically has become a significant study task.When the consumers choose a suppression plan,they have to evaluate the economic loss of the power quality as well as the suppression efficiency,so as to choose the best suppression plan and maximize the energy conservation and the comprehensive benefit.The main works are as below.This thesis starts out with the characteristics of the harmonic disturbance,and formulates the test and evaluation plan suitable for the project on the theoretical basis of national standard.Then in the energy conversion efficiency analysis of the harmonic suppression,it presents the harmonic loss calculation formula considering skin effect,in terms of the innovation of the wire harmonic loss suppression,and testifies the practicability of the calculation by experimentation.Based on the above energy conversion efficiency of harmonic suppression,an integrated and comprehensive evaluation indicator system is presented in the thesis from the consumer need,including technical indicator,economic indicator and adoption indicator.In the comprehensive evaluation,a synthetic weight method combining the subjective analytic hierarchy process with the objective entropy weight coefficient method is proposed.By calculating the correlation coefficient between the indicator of the evaluation plan and the ideal indicator using grey incidence theory,the suppression plan suitable for the consumer need is acquired.The thesis takes ground measurement of an automobile factory in Shanhai and analyzes its power quality,and the results show that the fifth harmonic current of the factory is unqualified.In order to solve the problem of power quality,the thesis puts forward three kinds of suppression.By using the presented evaluation method,the thesis provides feasible suppression plan for the factory,which obtains good feedback.