Integrated multifunctional power converter for small electric vehicles

This paper proposes an integrated multifunctional power converter topology, where a traction battery charger (TBC), an auxiliary battery charger (ABC), and a motor drive converter (MDC) merge into an effective system. Traction battery charging, auxiliary battery charging, and motor driving operation modes can be realized by sharing power components. For the battery charging mode, a single-phase power supply charges the traction battery, and the circuit is capable of power factor correction (PFC) and active power decoupling (APD) (G2V mode). For the purpose of enhancing its charging power, the traction battery can also be connected to a three-phase power supply. For the battery discharging mode, the traction battery can feed energy back to a single-phase grid or a three-phase grid (V2G mode). When necessary, the traction battery can charge an auxiliary battery through a DC–DC converter (T2A mode). In the motor driving mode, the energy of the traction battery is used to drive a motor (T2M mode). Each of the charging modes can be implemented under the galvanic isolated condition. Power relays are used to switch the operating modes of the proposed topology.