Research On Energy Efficiency Assessment And Optimization Of Distribution Network Connection Mode

The distribution network is an important part of power system and the main load-power supply center.Its efficient and economic operation is critical to implement energy efficiency management,energy consumption reduction of power system.The connection mode is the core structure of distribution network,which is related to whether it can operate safely,reliably and economically.Therefore,it is particularly important to study the grid structure of distribution network and optimize its wiring mode.Based on analysis of typical wiring mode of distribution network,this paper proposes a comprehensive evaluation index system and evaluation method for the wiring mode of distribution network,and based on which,proposes the optimization measures for the wiring mode.Firstly,it analyzes the main wiring methods of high-voltage and medium-voltage distribution networks,focusing on the medium-voltage system,and analyzes the typical wiring methods of overhead lines and cable lines.From the line load rate,line contact way etc.,each type of connection mode is compared.Taking a 10 k V distribution network in a regional area as an example,the lines,transformers,switches,etc.are analyzed,and the current existing problems are proposed from the aspects of network structure,load distribution,and power supply area division problem.Secondly,from the three aspects of safety,reliability,and economy of connection mode in distribution network,a comprehensive evaluation index system for distribution network including the target layer,criterion layer and index layer is constructed.And based on the relevant requirements of distribution network planning and design,the evaluation criteria of various type indexes are analyzed.Based on the subjective and objective weighting methods of analytic hierarchy process and entropy weighting method,a comprehensive evaluation method based on combined weighting method is constructed.Aiming at the example of a regional distribution network,the comprehensive evaluation and analysis of connection mode is carried out by using proposed comprehensive evaluation method.Finally,based on the typical characteristics of regional medium-low voltage distribution network,the optimization principle of distribution network connection mode is proposed,including the optimization principle of overhead line and cable line,the optimization goal of distribution network frame is proposed.In order to improve the adaptability of artificial intelligence optimization algorithm in the application of distribution network structure optimization,an improved genetic algorithm considering the topological characteristics of distribution network is proposed.The algorithm adopts dual-objective optimization considering the smallest network loss and smallest node voltage deviation.The IEEE 33-bus power distribution system is analyzed by a numerical example.The results show that proposed algorithm can improve the loss and voltage deviation of original network,and the improvement effect of proposed algorithm is better than traditional single-objective genetic algorithm.Several typical optimization measures for the wiring of distribution network are proposed,including changing the wiring mode,shortening the power supply radius of the line,increasing the cross section of the conductor,and increasing parallel line operation.