Game Theoretical Energy Management of EV Fast Charging Station with V2G Capability

Grid modernization, transportation electrification and alternative energy technology applications are interconnected with electric vehicle grid integration (EVGI) to form the energy internet. The EVGI management strategies incorporating both charging and discharging is one of the most common research problem in this area. It becomes more complicated when renewable energy is added as a source and implemented in commercial scale. In this article, a community based commercial electric vehicle (EV) fast charging station with vehicle to grid (V2G) power supply capability is proposed. The charging station load is supplied by photovoltaic (PV), energy storage system (ESS), EV discharge power and the grid. Dynamic pricing, user behavior based EV load model and grid loading conditions are considered in the model. For optimum sizing of the components, HOMER software provided by National Renewable Energy Laboratory is used. A non cooperative Stackelberg game theory is proposed for energy management. The results are compared with a conventional sequence based control algorithm.The proposed algorithm shows lower cost of energy (COE) for EV charging, and have surplus income from system to grid (X2G) energy sales. Thus, from the charging station perspective it can generate profit, also it can be beneficial for EV owners if they can manage their charging and discharging time according to the announced charging/discharging prices.