Research On Operating State Evaluation And Structure Optimization Strategy Of Low-Voltage Distribution Network

Distribution networks are one of most important links in power transmission.Low-voltage distribution networks connect with load.Low-voltage distribution networks directly affect operating state and overall economic benefits.The focus of this paper is how to quickly and easily select bad operating state networks from many low-voltage distribution networks,and design feasible optimization program.In order to solve the problem,that many influences effect low-voltage distribution networks operating state,but there is no reasonable evaluation index system,the paper proposes low-voltage distribution network operating state evaluation based on G2-entropy method.Firstly,the evaluation index system is established from the line state and network state.Secondly,the indexes are processed,so that each index value is in [0,1].Then use G2 method based on function driven,join the expert experience,to get the subjective weight of each index,and use entropy weight method based on the difference between data to get the objective weight of each index.Finally,the comprehensive weight of each index is obtained by using the Lagrange optimal multiplier method,then the evaluation function of operating state of low-voltage distribution network is obtained,and the operating state of low-voltage distribution networks is evaluated based on the function value.The validity and feasibility of the evaluation method are verified by the analysis of several low voltage distribution networks in a certain area.Bad operating state networks,selected from many low-voltage distribution networks,are studied on structure optimization strategy.Firstly,the topological structure,line parameters,power user phase,load state and power datum are collected from the bad.Secondly,build model from the datum,and simulate.According to the structure optimization,combining the index of the lines and networks,form optimization strategy of topological structure.The validity and economy of the optimal strategy is checked by analysis of the two bad.Therefore,according to the low-voltage distribution network operation state evaluation algorithm and the topological structure optimization strategy,easily and quickly select bad networks,and propose scientific,economical and reasonable targeted optimization strategy for guiding the design the structure optimization program of low-voltage distribution networks.