Enhancing the Performance of Wearable Wireless Power Transfer Systems

In this paper, the performances of wearable Wireless Power Transfer (WPT) systems are enhanced using ferromagnetic materials. The effects of the human body on the Power Transfer Efficiency (PTE) of a Conformal Strongly Coupled Magnetic Resonance (CSCMR) WPT system are further investigated. Two pairs of CSCMR, one on FR-4 PCB and one on flexible ferrite sheet are designed to operate at the 27.12 MHz ISM band. Simulations and measurements of these two configurations were performed on 26 different locations on the human body. It is found that printing CSCMR WPT systems on ferromagnetic substrates (i.e., ferrites) can prevent the reduction of PTE by isolating the effects of the human body.