Design of a Wireless Power Transfer System Based on Dual-Class E Self-Resonant Synchronous Rectifier

Wireless Power Transfer technology operating at megahertz is widely considered to be promising, which is used for the medium distances at a medium power. It is known that the Class E inventor and rectifier are suitable for high frequency Power converter. This paper derives and analyzes a Class E rectifier, then reports a Dual-Class E self-resonant synchronous rectifier used for parameter design of a MHz WPT system. The input impedance is derived from the analysis of the class E rectifier. The parameters of the coupled coil and BPF filter are designed and optimized in an example 2.5-MHz WPT system based on the input impedance. In a validation experiment, the experimental results are in good agreement with the analytical results and simulation results. In the experiment, the 2.5-MHz WPT system where mutual inductance coefficient (k=0.144) can achieve up to 80% efficiency at 20 W.