Long-Distance and High-Power Capacitive Power Transfer based on the Double-Sided LC Compensation: Analysis and Design

This paper proposes to use the double-sided LC compensation circuit to realize the long-distance and high-power capacitive power transfer. The targeted transfer distance is 150mm for the vehicle charging application, resulting in a loosely-coupled system. The circuit working principle and the transfer efficiency are provided, which indicates the duality with the conventional series-series compensated inductive power transfer system. Using the same capacitive coupler, two load conditions (the constant resistive load and the constant voltage load)are analyzed for the practical applications. The analysis of the CPT system provides the guideline to design and optimize the LC-compensated system. The experimental results show that kW level power transfer can be achieved through 150mm distance with dc-dc efficiency from the dc source to the dc load to be around 88%.