Implementation of Vehicle to Grid Infrastructure Using Fuzzy Logic Controller

With high penetration of electric vehicles (EVs), stability of the electric grid becomes a challenging task. A greater penetration level would demand a proper coordination amongst the various EVs as they charge or discharge to the grid. Coordination here refers to controlling the charging and discharging patterns of different EVs depending on their individual battery states and the present grid condition. Therefore, a good coordination between EVs is required for making the grid stable. With high penetration of EVs, the vehicle to grid (V2G) concept can be explored where excess energy of the battery can be supplied back to the grid in controlled fashion. Discharging EVs' battery energy to the grid in coordination can make V2G utilization as distributed energy storage. Charging EVs in coordination can flatten the voltage profile of a distribution node. In this work, a typical distribution system of a city is modeled to demonstrate V2G capabilities such as meeting peak demand and voltage sag reduction. The simulation of the distribution system with V2G capabilities are tested using fuzzy logic controller (FLC). Two controllers have been developed, namely the charging station controller and the V2G controller. Together they decide the proper energy flow between the EVs and the grid. Energy discharge to the grid from EVs or energy required for charging EVs is controlled and tested for the real time scenario.