Research On Multi-objective Optimized Scheduling Strategy For Charging And Discharging Of Electric Vehicles And Cost-optimal Routing To Charging Stations

As a new type of load,vehicle-to-grid can cause a series of effects on power systems.The main troubles are as the following: peak load being further increased,distributed network load partly overloading,portion nodes of power grid voltage being too low,the increasing network losses,as well as the distributed network transformer being overloading,and so on.With the development of electric vehicle faster and faster,the uncertainty over time and space of vehicle-to-grid is the essential problem.The massive application of control strategy makes vehicle-to-grid charging orderly,which is a hot topic of the research.In view of the development of electric vehicles in China,numerous research demonstrates that ordinary access of vehicle-to-grid has less effect than the disorderly access.Based on the control strategy analysis summary of vehicle-to-grid,pointed out the shortcomings in control strategy of vehicle-to-grid,and made a further analysis,put forward reliable references to control strategies of vehicle-to-grid.The effective control strategy can reduce the impact of electric vehicle charging and discharging on the power grid.In order to minimize the load mean variance of the distribution network and minimize the peak valley difference of the system load as the objective function,a mathematical model of the power grid load fluctuation is set up from the distribution network.Taking into account the common interests of both the power grid and the users,the multi-objective optimization scheduling model of electric vehicles is established in the user side with the minimum cost of charging and discharging the electric vehicle as the objective function of the optimization.Based on a commercial building load simulation example,the constant inertia particle swarm optimization algorithm is used to solve it.The simulation results show that: the dispatching strategy guided by TOU pricing can reduce the peak valley difference and improve the users' economy.With the increase of average electricity price,the effect of peak shaving is remarkable,and the user cost will increase as the average electricity price rises.Electric vehicles convert electricity into kinetic energy that drives cars,green,environmentally friendly and pollution-free.The government is actively promoting the development of electric vehicles,and the number of electric vehicles has been developed.When the amount of electric vehicle can not meet the needs of electric vehicle users,electric vehicles need to supplement their electricity.How to choose charging stations reasonably and effectively is a very worthwhile problem.In this paper,an economic choice method is proposed for how to choose charging stations for electric vehicle users in the region.By setting up the information interactive platform of the electric vehicle users and each charging station,the queuing theory model is introduced to calculate the time cost of the electric vehicle to reach the charging station,while the mileage cost is further calculated.Based on the previous research results,under the reasonable layout of the electric vehicle charging station in the region,the single target letter is selected to select the charging station to determine the most economical way.Electric vehicle users choose the electric vehicle charging station to charge at the lowest cost.