Research On The Responsibility Evaluation Of Multi Source Harmonic And Three-phase Unbalance

With the development of economy and the progress of society,the problems of harmonic pollution and three-phase unbalance in modern power grid are becoming more and more serious.Reasonable division of electricity supply and electricity between the two parties at the public connection point(PCC)bear the responsibility,is the power quality management and management of the premise.This paper focuses on the study of multi-source harmonics and three-phase unbalance responsibility division and its assessment methods.In this paper,a dynamic full-scale circuit for harmonic liability analysis is established.The R,L,C and harmonic current source parallel model based on the parameter identification of the current decomposition method is adopted.The system side adopts the dominant wave Which is based on the equivalent circuit,analyzes the existing definition of harmonic liability and the existing problems of the evaluation index,clarifies the physical meaning of the harmonic liability,and puts forward the harmonic responsibility division based on the active direction discrimination Principle,five kinds of harmonic liability quantitative calculation index are proposed,the harmonic liability evaluation index system is established,and the correctness of the result is verified by the IEEE14 node simulationIn this paper,the system full-scale method is extended to the user network of multi-harmonic source,and the equivalent model of single-bus multi-harmonic source is established.A step-by-step method for multi-user harmonic liability sharing is proposed,The harmonic liability between the power supply side and the user,the user and the user is calculated,and the corresponding harmonic liability evaluation index is calculated and the correctness of the result is verified by the IEEE14 node simulationIn this paper,a three-phase unbalance traceability method based on equivalent model of weight coefficient is proposed.This method can judge whether the unbalance of the three-phase system is caused by the user side or the system side.For the system and the user,The negative sequence full-value model is proposed.Based on the model,the principle of the definition and responsibility division of the three-phase unbalanced liability of the fundamental wave and t he four categories of negative sequence responsibility indicators for the quantitative calculation of the unbalance liability are put forward,and the three-phase unbalance liability evaluation index system,and the correctness of the result is verified by the IEEE14 node simulation...