Optimization Of Distribution Networks With Electric Vehicle Charging And Discharging

Electric Vehicle(EV)has the advantage of energy conservation and environmental protection,and has been increasingly used by people.However,with the increase in the number of electric vehicles,there will also be a series of problems.The charging of electric vehicles will increase the load on the distribution network,which may lead to grid overload,which poses a certain threat to the stable operation of the power system.In order to minimize the impact of electric vehicle charging and discharging on the distribution network,it is necessary to strengthen the planning and construction of the power grid,improve the intelligence and adaptability of the power grid,and meet the needs of the rapid development of electric vehicles.As an important supporting facility for electric vehicles,it is also necessary to study the construction and planning of electric vehicle charging stations and their impact on the distribution network.This paper mainly studies the optimization and operation of distribution network planning including electric vehicle charging stations,which is mainly divided into the following aspects:First,it introduces the planning and modeling of the location of electric vehicle charging stations,including the division of charging demand areas and the establishment of location models.The goal of the location model is to minimize the sum of the construction and operation costs of electric vehicle charging stations and the charging costs of users,with the service radius and capacity of electric vehicle charging stations as constraints.Then,based on genetic algorithm,the location model is solved to optimize the optimal installation location of the electric vehicle charging station.Secondly,considering that Soft Open Point(SOP)as a power electronic device,can optimize the operation of the distribution network by controlling the active power of the line,this paper studies the SOP location and capacity model in the distribution network with electric vehicle charging stations.The model aims to reduce network losses in the distribution system and maximize user satisfaction with charging.Based on the functional principles of SOP and its own operational constraints,it plans and determines the capacity of electric vehicle charging stations,as well as the location and capacity of SOP.Thirdly,the nonlinear system power flow constraints and SOP self constraints in the above model are transformed into second-order cone forms for programming simulation and solution.The operational performance of the distribution network is analyzed for different scenarios such as accessing electric vehicle charging stations at different locations and numbers,and planning SOP at different locations,numbers,and capacities.The simulation results show that reasonable location and sizing of SOP devices in the distribution network can significantly reduce the network loss,make node voltage,and charging satisfaction of electric vehicle users better.