Design of High-Efficiency WPT Battery Charging System with Constant Power and Voltage

Abstract

In wireless power transfer (WPT) systems, efficiency and battery charging speed are very important factors. Due to the wide range of loads, achieving high efficiency at a constant frequency is not possible in such systems. Also, choosing the right charging scenario can have a significant effect on improving the charging speed. In this paper, a series-series (SS) WPT system with a semi-active rectifier (SAR) is proposed, which uses the variable frequency and the impedance matching mechanism simultaneously to achieve the highest efficiency. Also, to increase the charging speed at the beginning of the battery charging, a constant power-constant voltage (CP-CV) charging algorithm is used.