Research On Optimization Design And Energy Management Strategy Of Electric Vehicle Fast Charging Station With Energy Storage

As a new industry,energy storage technology has played an important role in modern power system.The optimal design and energy management of electric vehicle fast charging load and energy storage system can improve the access capacity of centralized electric vehicles’ charging in the distribution network.Furthermore,the scientific and reasonable use of electricity by electric vehicles can realize the low-carbon and environmental protection,and reduce costs of the distribution network.Therefore,it is of great significance for the safe operation of power grid to apply the energy storage system to the fast charging station and optimize its management.The demand of large-scale centralized access of electric vehicles to the urban distribution network is analyzed in the paper.The key technology of the design scheme of the coordinated planning and operation of the fast charging station in the intelligent distribution network is studied.Considering the centralized access of large capacity load,power quality and economic efficiency of the distribution network,the interaction mechanism,coordination control,optimization design and comprehensive energy management theory of EV charging are proposed based on the latest theories.Firstly,the influence of road network structure,traffic information and users’ journey loss on the location and capacity of the charging station are analyzed.The influence of the traffic density in the road network on the service scope of the charging station is reflected by the weights.Using the queuing theory,the charging process of the electric vehicle in the station is described.The system loss rate corresponding to the number of charging piles is analyzed under different arrival rates.Then,the planning scheme based on the minimization of the whole social cost is proposed on the interests of both the charging station operator and the electric vehicle users.This planning scheme realizes the optimization of location,fixed capacity,division of service scope and planning scheme of the fast charging station in urban area.Secondly,adopting data mining theory and the probabilistic prediction of previous charging load data,the selection of factors affecting charging load is achieved.The charging state of power grid and the charging state of energy storage quick charging station can be descripted with finite two-dimensional Markov chain of life and death,and a stochastic charging prediction model for energy-storage fast charging station is established.The charging load of EV charging and storage integration station under multi-energy access are predicted effectively.Furthermore,the guidance for the daily operation of the quick charging station with energy-storage system is provided.Finally,the model and the operation constraints of each unit in the energy storage fast charging station are analyzed.An energy optimization model is built,which includes the rapid charging demand of electric vehicles,power battery charging requirements,battery equalization use constraints,power balance constraints,etc.The energy management optimization structure is designed,which includes the lowest cost and the minimum system load fluctuation.The output combination of each unit is arranged reasonably and efficiently.And the economic and optimal operation of the fast charging station can be realized with multi energy access.