Inductively coupled wireless powertransfer with class-E^2 DC-DC converter
Tomoharu Nagashima, Kazuhide Inoue, Xiuqin Wei, Elisenda Bou, Eduard Alarcon, and Hiroo Sekiya
The 21th European Conference of Circuits Technology and Devices(ECCTD2013), Sept., 2013. [pdf document]

<Abstract>

This paper proposes an inductive coupled wireless power transfer (WPT) system with class-E2 dc-dc converter along with its design procedure. The proposed WPT system can achieve high power-conversion efficiency at high frequencies because it satisfies the class-E zero-voltage switching and zero-derivative-voltage switching conditions on both the inverter and the rectifier. By using the class-E inverter as a transmitter and the class-E rectifier as a receiver, high power-delivery efficiency can be achieved in the designed WPT system. By using the numerical design procedure proposed in the previous work, it is possible to design the WPT system without considering the impedance matching for satisfying the class-E ZVS/ZDS conditions. The experimental results of the design example showed the overall efficiency of 85:1 % at 100 W output power and 200 kHz operating frequency.