Power Flow Control of Capacitive Power Transfer by Soft Switching of Extra Capacitors in Class E Converter

This paper proposes a new power flow control method for Capacitive Power Transfer (CPT) systems by switching extra parallel capacitors of a class E converter. The control method is implemented in a suboptimum operating mode of the class E converter, which ensures zero voltage switching (ZVS) over a specified range of the parallel capacitance. Equations are derived to describe the characteristics of the system operation and determine the soft switching conditions. Simulations and experimental results have shown the proposed control method can adjust the output power effectively while maintaining ZVS operation, validating the proposed control method.