High-Efficiency Design and Close-loop Power Distribution Control for Double-Frequency Double-Load Magnetically Coupled Resonant Wireless Power Transfer System

In multi-load magnetically coupled resonant (MCR) wireless power transfer (WPT) systems, it is an urgent issue to satisfy the power requirement of loads with high efficiency. In this paper, a multi-frequency concept is introduced to solve this issue. By employing the coil structure with a single transmitter and two receivers, a double-frequency circuit configuration driven by two inverters is implemented to transfer power to loads. Based on the influential factors on transmission characteristics revealed from the equivalent circuit model, a high efficiency design method and a power distribution control strategy are put forward respectively. Finally, a prototype of the double-frequency double-load MCR WPT system is built in the laboratory and the experimental results have shown the validity of the proposed high efficiency design and power distribution control methods.