Research On Orderly Charging Strategy And Charging Piles Configuration Of Electric Vehicles In The Station Area

With the rapid growth of the scale of electric vehicles,electric vehicles,as an increasingly important random load,have a greater impact on the distribution system in the station area.In particular,the disorderly charging behavior of a large number of electric vehicles leads to more uneven distribution of power load,and the peak-valley difference continues to increase,making the distribution transformer capacity more prone to overload and capacity expansion.Therefore,under the existing distribution transformer capacity,the use of orderly charging piles with orderly charging function and the corresponding orderly charging strategy can effectively alleviate the contradiction between the limited distribution transformer capacity in the station area and the surge in the charging demand of electric vehicles,and avoid resource waste and excessive construction.With the promotion of the intelligent transformation policy of charging piles,this paper focuses on the orderly charging strategy and configuration of charging piles in the station area.The specific research and findings are summarized as follows:(1)Based on the in-depth analysis of electric vehicles charging methods and charging facilities,the probability distribution model of electric vehicles trip characteristics and the disorderly charging load model are established;The negative impact of large-scale electric vehicles disorderly charging load on the distribution system is analyzed based on Monte Carlo algorithm.(2)A multi-objective orderly charging strategy for electric vehicles is proposed.Firstly,the membership function is used to divide the peak and valley periods of transformer load and set the charging price to promote the orderly charging of electric vehicles.;Then,a multi-objective orderly charging optimization model for electric vehicles is established with the optimization objectives of maximum charging completion rate,minimum charging cost and minimum load peak-valley difference.An improved binary particle swarm optimization algorithm is proposed to solve the model to obtain the orderly charging plan of electric vehicles,so as to stabilize the load fluctuation of distribution transformer,meet the charging demand of electric vehicles,and reduce the charging cost of electric vehicles.(3)A method of charging piles configuration based on double-layer optimization in the station area is proposed.This method determines the configuration type of charging piles.Taking the return on investment of charging piles as the upper optimization objective and the orderly charging strategy of electric vehicles as the lower optimization objective,a double-layer optimization model of orderly charging piles configuration is established and solved to obtain the optimal configuration proportion of orderly charging piles,which takes into account the interests of the user side and the power grid side,and provides a certain guiding idea for the intelligent reformation of charging piles in the station area.(4)An orderly charging verification device for electric vehicles is developed.The device includes orderly charging controller and orderly charging concentrator.The hardware circuit and software program of the orderly charging controller are designed,and the software program and terminal display interface of the orderly charging concentrator are developed.The experimental test shows that the orderly charging verification device can realize the control of the switching state of the charging pile and improve the ability of the orderly management of the charging pile.