Integration of EV fast charging station into a DC-based microgrid

A wide diffusion of fast and ultra-fast stations could affect power quality and the safe operation of distribution networks. Therefore, proper strategies for the optimal management of vehicles, along with the combination of storage systems and renewable sources, is required in order to avoid grid problems. In this context, DC microgrids combining renewables sources, storage systems and electric vehicle stations are demonstrated to foster the integration of these facilities, also allowing optimal exploitation of their functionalities. This study aims at inspecting the effect of electric vehicle fast-charging integration on the optimal operation of a DC-based supply infrastructure and its interaction with the distribution grid. The proposed methodology employs a mixed-integer linear optimization considering economic and technical targets and taking into account charging station cable losses by means of linearization technique. The impact of stochastic optimization and objective combination is further discussed. The procedure is implemented into a DC microgrid integrating a fast-charging station based on realistic facility data, and several scenarios are simulated and compared by means of cost and power loss evaluation.