Driven by the increased electricity demand and stricter environmental requirements,microgrid is one of effective solutions for the future smartgrid and global energy inter-connection.The global automotive industry is accelerating its development towards intelligence and electrification.A large number of electric vehicles(EV)will increase the upgrading pressure of power grid.Microgrid or microgrid cluster providing electric power for EV charging station will reduce the electric energy demand from main grid.At the same time,with the increase of the number of electric vehicles,its function as "energy storage" can effectively reduce the demand for energy storages of microgrid with high penetration rate of renewable energy,and promote the development of distributed photovoltaic and wind generation.This dissertation focuses on microgrid energy management with EV charging station in the industrial zone or campus,mainly to address the coordinated charging of EV charging station and taking electric vehicles as mobile energy storage to support the operation of microgrid.The main research includes: The output and cost mathematical model of distributed generation,the optimization mathematical model of coordinated charging for EV charging station,and a day-ahead optimal scheduling strategy of microgrid with EV charging station.This work has achieved win-to-win between EV stakeholders and microgrid,which can also promote the development of distributed renewable energy.The main work of this dissertation is as follows:(1)A day-ahead optimal scheduling strategy of microgrid is proposed to minimize the operating cost.Firstly,the output power and operating cost model of photovoltaic generation,wind turbine generation and diesel generation system are established.Based on this,a day-ahead optimal scheduling model of microgrid is built.The mixed integer linear programming algorithm is used to solve the problem to obtain the initial generation plan of distributed generation of microgrid without EV charging station,which is as the basis for time-of-use(TOU)power price-fixing model.Finally,the optimal scheduling model is also the theoretical formula for solving the day-head optimal generation plan of microgrid with EV charging station.(2)An coordinated charging mathematical model of EV charging station is established,including the day-ahead TOU price-fixing model and the coordinated charging/discharging model.Firstly,the characteristics of electric vehicles and the factors affecting the load characteristics of the EV charging station are analyzed,and the load forecasting for uncoordinated charging electric vehicles based on Monte Carlo method is made.Secondly,considering the generation cost of microgrid and the discharging cost of electric vehicles,the day-ahead TOU power price mechanism is fixed.Finally,the coordinated charging model of EV charging station guided by electricity price are established,then the optimal power distribution of EV charging station is obtained.(3)The energy management system of microgrid with EV charging station is established.A model based on hierarchical optimization theory is proposed,which takes microgrid as the upper layer leader and the EV charging station as the lower layer follower.Two cases of typical day(including normal weather and bad weather)are selected to verify the model,and the simulation results show that the hierarchical optimization energy management system of microgrid with EV charging station could realize coordinated charging of electric vehicles,which also act as mobile energy storage to support the operation of microgrid,and achieve win-to-win between EV stakeholders and microgrid. |