A loosely coupled inductive wireless power transfer systems with class-E transmitter and multiple receivers
Hiroo Sekiya, Kazuhide Inoue, Tomoharu Nagashima, Tadashi Suetsugu, Shotaro Kuga, Xiuqin Wei, Kenichi Shirota, Hironobu Hatamoto, and Satoru Shimizu
2014 IEEE Energy Conversion Congress and Exposition (ECCE2014), pp.675-680, Sept., 2014. [pdf document]

<Abstract>

This paper presents a design procedure for dc-to-dc WPT systems with multiple receivers. For achieving high power-transfer efficiency, the class-E inverter and the class-E rectifiers are applied to the transmitter and the receivers, respectively. By using the numerical design algorithm, we can obtain the accurate component values for achieving the class-E ZVS/ZDS conditions and the impedance matching of the secondary side without system analyses. Additionally, the inductor designs are discussed from the magnetic-component design knowledge [13]. The WPT system with five receivers was designed and circuit experiments were carried out. The power-transfer efficiency was 84.4 % with 5.7 W output power in total.