Implementation of High Efficiency Coupling Coil in Wireless Power Transfer System

Generally, a four coil topology is implemented in a resonance wireless power transfer system. This paper investigates the relationship of the impedance, efficiency, transfer distance and mutual inductance in the four coil design. A design procedure is proposed to implement the four coil geometry parameters. To verify the design coil parameters, a four coils are accomplished in this work. The measurement shows the maximum efficiency achieves 92.9% in a coupling distance of 6.5cm.