An Ultra-Low Weight Bidirectional Back-End PFC Topology

This paper presents a 3.3 kW bidirectional Back-End Power Factor Correction (PFC) topology with a single stage in the on-board converter for Inductive Power Transfer (IPT) for Electric Vehicle (EV) charging. Since the proposed topology eliminates the input and output interfaces, the primary (off-board) resonant inverter or secondary (on-board) active rectifier must be the responsible of the tasks previously done by the interfaces: power control by Voltage Regulation (VR) and PFC. As the proposed topology does not require intermediate energy storage elements, high-power density, low-profile and low-weight converter is possible. A Phase Locked Loop (PLL) easily can be implemented without the necessity of communication between the off-board and on-board converter. A demonstrator with Gallium Nitride (GaN) semiconductors has been developed to validate the concepts presented here. Experimental results for both power transferring modes are presented: Grid to Vehicle (G2V) and Vehicle to Grid (V2G).