Integrated single-phase PFC charger for electric vehicles

This paper discusses a converter structure appropriate for charging the batteries of an electric vehicle. The structure is obtained by a transformation of a conventional three-phase inverter, which is already present in an electric vehicle’s powertrain system. Since the motor inverter’s semiconductor components and the electric motor’s windings form the battery charger’s circuit, a reduction in the powertrain system’s size and weight is achievable. The proposed fully integrated battery charger can operate in buck and boost modes, while providing power-factor correction capability continuously. This paper also proposes an input current control strategy which ensures smooth operating mode transitions, which occur during the operation of the battery charger. The control is entirely implemented within a microcontroller and ensures operation with a high power factor and low total harmonic distortion of the input current. The performance of the discussed converter using the proposed control scheme was verified experimentally.