Three-phase bidirectional battery charger for smart electric vehicles

A three-phase battery charger for electric vehicles is proposed in this paper. The charger is bidirectional, allowing the Charging and Vehicle to Grid operation modes. A novel Balanced Sinusoidal Source Current control strategy is proposed so that the charger demands or injects into the grid a perfect sinusoidal and balanced source current in phase with the positive sequence fundamental component of the phase-to-neutral grid voltage, achieving a unity displacement power factor. In this way, the charger turns the car into a smart vehicle, reducing the existing problem of harmonic current demand by electric and hybrid vehicles and improving the power quality of the electric power system. The topology and control stage of the charger are shown. Simulation tests are conducted to validate the proper operation of the charger under sinusoidal, distorted and unbalanced source voltages.