A High Efficiency and Compact Inductive Power Transfer System Compatible with Both 3.3kW and 7.7kW Receivers

This paper proposes a high-efficiency, compact inductive power transfer (IPT) system for the stationary charging of electric vehicles, which contains a single transmitter and two receivers of different power. The transmitter is compatible with both 3.3kW and 7.7kW receivers. A double-sided LCC compensation circuit is adopted to realize the IPT system. In the magnetic coupler design, the external compensation inductors are integrated into the main coils without introducing extra magnetic couplings. The design procedure of the circuit parameters is provided, in which high system efficiency is maintained for both the 3.3kW and 7.7kW receivers. A prototype is implemented to validate the proposed system. The transmitter coil size is 500mmX500mm, the 3.3kW receiver coil size is 300mmX300mm, and the 7.7kW receiver size is 420mmX420mm. When the air-gap is 150mm, the 3.3kW receiver system achieves a dc-dc efficiency of 95.4%, and the 7.7kW receiver system achieves a dc-dc efficiency of 95.2%.