Influence Of Large-scale Application Of Electric Vehicles On Distribution Network And Its Control Strategies

Nowadays,all countries in the world are under the great pressure from energy consumption and environmental pollution.Electric vehicles,with the advantage of less pollution and easy-consumption of new energy,are receiving more attention from the whole society.With the support from the government,the electric vehicle industry develops rapidly in China.In the future,the number of electric vehicle will increase very fast,which will drive the development of charging infrastructure.At the same time,the increase of charging demand will be a new challenge to the power system.The influence of large charging demand on the distribution network becomes important research topic.Based on the resident trip survey data,residents travel time distribution and vehicles distance distribution are modeled in this paper by identifying and analyzing these data with statistical methods.By selecting the Nissan Leaf as the research object,electric vehicle charging demand is modeled with the Monte Carlo simulation method.Besides,the charging demands in different seasons and their influence on distribution network load curve are analyzed in this paper by considering the factor of temperature and seasons.And the results show that it is necessary to control the charging load in summer.To reduce the influence on the distribution network of charging demand,0-1interge programming is modeled in this paper by adjusting the charging time and power,with the objective of minimize the load fluctuation.Branch and bound method is used to solve the model and the strategy of charging for large scale EVs is obtained.With the simulation of a medium distribution network,the influence of charging demand on the network,in summer and winter are analyzed and compared in this paper.The results show that random charging will increase the fluctuation of the network load curve and voltage,which will affect the quality of the power supply.Moreover,the results prove that the optimized charging strategy will reduce the fluctuation of the load curve and voltage.Finally,the economic benefits of the optimized charging strategy are analyzed and advice on promoting the policy is given.