The Impact Of Electric Vehicles Charging On Distribution System And The Orderly Scheduling Research

Fossil energy consumption is growing,the problems of environmental pollution and global warming are increasingly serious,one of the main causes of these problems comes from the human fuel vehicle activities.Relative to the traditional fuel cars,electric vehicles have the advantages of high efficiency and cleaning.Therefore,Chinese auto companies are vigorously promoting the development of electric vehicles.Especially in recent years,the great progress of the electric vehicles’ battery technology and the emergence of new battery technology are accelerating the promotion of the popularity of electric vehicles.When large-scale electric vehicles into life,taking into account the people’s habits,the charge load must be high density continues to appear after work.This huge charging load will bring some impacts and adverse effects to the distribution network operation.Therefore,it is necessary to study the effects of electric vehicle charging on the distribution network and to optimize the charging load to reduce the adverse effect.Firstly,the establishment of electric vehicle charging load model and accurate calculation of the size of the charging load is to study the impact of electric vehicle charging on the distribution network.This paper summarizes the main factors that affect the charging load,based on the US Department of Transportation statistics,the electric vehicle charging load model is established.And then through the establishment of the model and the use of Monte Carlo method to generate disorderly load curve,the influence of electric disorderly charging on the daily load curve of distribution network is analyzed,the simulation results show that the disorderly charging load will deteriorate the distribution network.Secondly,the simulation is based on the chasing method in the power flow calculation of the low-voltage distribution network,which has faster calculating speed,taking up less memory to newton laphson method.At the same time,according to the size,time and node of the distribution network,the control variable method is used to analyze the influence of the charging load on the distribution network under different scenarios.The simulation results show that when the size and time are the same,the node is different,the charging load access node is closer to the head of the same line,and the influence of the distribution network is small.When the size and node are the same,the time is different,the impact that the high level of time access load than in the low level of access load on the distribution network.When the time and node are the same,the size is different,the greater the charging load,the greater the impact on the distribution network.Furthermore,the relationship between the variance of load fluctuation and the network loss is deduced according to the Cauchy-Schwarz inequality.The simulation results show that the smaller the variance of the load fluctuation,the more flat the load curve,the smaller the distribution network loss.Finally,through the orderly scheduling of electric vehicles to achieve the electric vehicle charging load optimization.Considering the initiative of user behavior in the scheduling process,an orderly scheduling strategy is proposed to consider the charging selection of electric vehicle users.The optimal scheduling model of electric vehicle load is established by taking the minimum cost of charging and the variance of grid load as the goal,charging requirements and other conditions as a constraint,the multi-objective search algorithm based on particle swarm is used to solve the problem.The simulation results show that the orderly scheduling strategy is effective and has a certain reference value for the optimal scheduling of the charging load.