A Large-Area Free-Positioning SCC-WPT System for Movable Receivers

This letter proposes a novel free-positioning single-capacitor-coupled wireless power transfer system with a large area for movable receivers. The system utilizes the earth's ground as part of the power transfer path, allowing the coupling structure to consist of only one transmitting plate. In addition, one of the receiving plates can be replaced by the metal shell of the movable receiver. The coupling structure is optimized using ANSYS Maxwell to achieve better transfer performance while maintaining the free-positioning capability. In addition, the circuit model of the coupling structure is simplified, and the system model is established based on the four-coil topology. A 1 m × 1 m free-positioning experimental prototype is implemented, capable of delivering stable output power at any position within the transmitting plate. Experimental results demonstrate that the prototype achieves an output power of 538 W with a dc-to-dc efficiency of 84.7%.