An Electrolytic Capacitorless Bidirectional EV Charger for V2G and V2H Applications

In this paper, a bidirectional battery charger is proposed for grid-to-vehicle, vehicle-to-grid, and vehicle-to-home operations of electric vehicles. The proposed charger adopts sinusoidal charging to eliminate the use of electrolytic capacitors. A nonregulating series resonant converter is employed for isolation, thereby minimizing the ratings of the components and achieving zero-current switching turn ON and OFF of switches. Meanwhile, an ac-dc converter is employed to control each mode and their mode changes, making the whole control scheme simple and the mode changes seamless. A 3.3-kW prototype was built in the laboratory to validate the proposed concept. Our experimental results demonstrate that the proposed charger has high efficiency and can seamlessly switch between the three operation modes.