A Load-Independent Multi-Relays Wireless Power Transfer with Self-Regulation and Single Compensation Network

Wireless power transfer (WPT) technology is gaining prominence as a research focus in both industry and academia, particularly for applications where delivering power via metallic conductors is impractical. This paper introduces a WPT system designed for easy implementation near real-world demands, achieved through reduced circuit components and manufacturing costs. The system efficiently supplies power to various electrical devices that require constant-voltage (CV), constant-current (CC), or both CV/CC modes simultaneously like lithium-ion (Li-Ion) batteries. A single compensation network enables straightforward attainment of either CV or CC output, facilitated by a load-independent power-stage and control methodology. Experimental results demonstrate a PWM-based resonant regulating rectifier (3R), achieving a maximum power transfer efficiency (PTE) of 74.5% under two loads positioned 300 mm apart from a half-bridge class-D power transmitter (Tx).