A Dual-Functional Single-Stage Receiver Circuit With Rectification and Power Regulation for Compact Wireless Charging Systems

This brief presents a dual-functional single-stage receiver (DSR) circuit that simultaneously performs rectification and power regulation, then ensures a compact wireless charging system. The DSR circuit features an ultra-simplified architecture consisting of only two MOSFETs and one filter capacitor. First, the operating stages and working principle of the DSR circuit are given. Then, the quantitative relationship between the charging current and the duty cycle of the pulse-width modulation (PWM) signals is derived. Second, a low-complexity control strategy is proposed, comprising a synchronous signal unit for generating two PWM signals and a closed-loop control unit for constant-current (CC)/constant-voltage (CV) charging. Simulation results verify the DSR circuit's stable rectification and accurate CC/CV charging performance across a wide range of equivalent load resistances. Finally, experimental results demonstrate that the maximum system efficiency can reach 92.8% at a charging power of 360 W. Compared with commonly used secondary-side power adjustment circuits, the DSR circuit offers outstanding structural and control simplicity for the WCS, mainly enabled by its single-stage dual-function architecture.