A Metamaterial Design for Suppression of Cross Interference in Multi-Frequency Multi-Load MCR WPT System

Magnetically coupled resonant (MCR) wireless power transfer (WPT) is capable of supplying power to multiple loads simultaneously. To realize load identification and efficient power distribution in multi-load MCR WPT system, a multi-frequency driving method was implemented. However, this methodology allows loads to receive power at different frequencies, leading to a cross interference among multiple loads and deteriorating the power distribution accuracy. In this paper, a double-frequency double-load MCR WPT system was investigated as an example. To suppress the cross interference in the system, a printed circuit board (PCB) type metamaterial slab was designed to reduce the equivalent mutual inductance between transmitter (Tx) and receiver (Rx) coils at non-targeted frequencies, blocking the transfer channel of non-targeted power components. The suppression effect to cross interference was confirmed by the experiment results.