Ultra-Compact Single-Stage Bidirectional Wireless Battery Charger for Electric Vehicles

This paper presents a 3.6kW wireless battery charger for Electric Vehicles (EV), based on a bidirectional back-end Power Factor Correction (PFC) topology without bulky dc-link capacitor. The proposed topology only requires wireless charging coils and the resonant tank as intermediate energy storage elements, increasing the power density and enabling the design of a low-profile power converter. A laboratory prototype with Gallium Nitride (GaN) High Electron Mobility Transistors (HEMT) has been developed to validate the topology concept and to analyze the performance. Experimental results for bidirectional power transferring modes are included in the paper: Grid to Vehicle (G2V) and Vehicle to Grid (V2G).