Design of 6.78 MHz Magnetic Coupling Resonant Omnidirectional Wireless Power Transfer Based on Class E² Conversion

Omnidirectional wireless transfer power technology is a promising application field for it has the advantages of easy to use, safety, and compact size. Based on the rapid development of today’s wide band gap power devices, a novel design of 6.78 MHz omnidirectional magnetic coupling resonant wireless power transfer converter based on GaN switches is proposed in this paper. The converter uses Class E ² topology inverter and rectifier to improve power conversion efficiency, and uses three independent coils in x, y, and z directions to realize omnidirectional magnetic field emission. A 10W prototype is made and tested to verify the feasibility of this novel design.