Enhanced planar wireless power transfer using strongly coupled magnetic resonance

A novel planar wireless power transfer (WPT) system using strongly coupled magnetic resonance is proposed. Additional layers of printed spiral coils (PSCs) are applied to the transmitter/receiver resonator of the 4-coil planar WPT system to improve the quality factor and transmission efficiency. In addition, by connecting multilayer transmitter/receiver resonators together using conductive shorting walls, the transmission efficiency is further improved. Five planar WPT systems using coplanar PSCs and printed loops have been investigated. The measured results show that the proposed design with two additional layers of resonators and shorting walls could improve the transmission efficiency from 77.27 to 84.38%.