A mutual inductance approach for optimization of wireless energy transmission

This work introduces a new approach of optimizing the efficiency of a wireless power transmission system in terms of mutual inductance. A circuit model was developed in PSpice to simulate the effect of mutual inductance by inductive coupling on power transfer efficiency. Experiments were conducted at 1.3 MHz with variations of distance between coils and coil sizes to change the mutual inductance in the equivalent circuit. Experimental results agreed well with the simulation model. The optimal mutual inductance to reach maximum power transfer efficiency for the inductive coupling system driven by a class-E amplifier was identified with respect to different coil sizes and distances. This method can guide the design strategy of the transmitter and receiver coils for specific applications.