Efficiency optimization of WPT system with a planar receiver for mobile applications

Abstract

ABSTRACTThis letter presents a wireless power transfer (WPT) system with a planar receiver for mobile applications. The proposed WPT system includes a source coil, a transmitter spiral (Tx coil), a rectangular receiver coil (Rx coil), and a rectangular load coil. In order to make a compact receiver, the Rx coil is placed in front of the load coil with a gap of 2 mm. In addition, the relation between the transfer efficiency of WPT system and the capacitance value of Rx coil is established. Experimental results show that by optimizing the capacitor embedded in Rx coil, it is capable of achieving a very high transfer efficiency. With an optimized capacitor Cx = 785 pF on the Rx coil, the transfer efficiency of the proposed system is comparable to a WPT system using a metamaterial (MTM) array. The proposed WPT system operates at 6.78 MHz. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1817–1819, 2016