High-efficiency magnetic coupling resonant wireless power transfer system with class-e amplifier and class-e rectifier

This paper presents a magnetic coupling resonant wireless power transfer (MCR-WPT) system. Two separated coils form a loosely coupled transformer. The primary side adopts a Class-E amplifier, which produces high frequency sinusoidal current to excite the primary winding, inducting a high frequency AC voltage in secondary winding. The secondary side adopts a Class-E rectifier to rectify the high frequency AC output of the series resonant tank. A procedure is also developed to optimize the design of the amplifier and the rectifier in this WPT system. As a result, the efficiency of the system can be as high as 79.6 % and the ZVS (Zero Voltage Switching) as well as the ZDS (Zero Voltage Derivate Switching) operation of the Class-E converter can be guaranteed.