Technical Feasibility of Modular Energy-Saving Control Strategies of Vehicle-to-Grid Charging Stations for Frequency Regulation

In future scenarios characterized by high penetration of Electric Vehicles (EV) and renewable power generation, it is important for the smooth functioning of the electrical grid that the users of electric vehicles participate to Vehicle2Grid (V2G) schemes. Despite this, the so-called range anxiety is still limiting the participation to V2G services. Given this, there is a growing attention in the literature about incentives and solutions which might relieve users' reluctance in transferring power from the battery of their electric vehicle to the grid. Hence, the present paper proposes three different modular V2G strategies, which on the one hand might motivate users to participate in the service and on the other hand might be effective for improving the behavior of the grid (namely, for frequency regulation). Through the proposed strategies, the user is explicitly given the opportunity to choose the level of involvement of their vehicle, safeguarding autonomy or maximizing potential economic gains from participating in the service. Three different implementations are explored, where the modulated quantities are respectively the maximum power delivered to the service, and the dead band and saturation frequencies. The results show that, despite a slight decrease in dynamic performance compared to standard vehicle-to-grid systems (no more than 18%), there are significant technical benefits for the grid, with energy savings on the vehicle side up to 53%. Based on this, the proposed modular V2G strategies can be considered very promising and their practical implementation should be supported.