Design and comparison of parallel and series resonant topology in wireless power transfer

Wireless power transfer is a very promising technology in industrial applications. This paper analyzes the difference of LC parallel and series resonant topology in wireless power transfer. With the three coils model as example, on the transmitter side, it is proven that the voltage source in parallel resonant mode is interchangeable with the current source in series resonant mode, under a certain transfer equation, in such a way to have the same output status. And on the receiver end, the topology selection is proven to be related with the load. For heavy load, the parallel topology has more advantages, while for light load; the series topology is the preferable one. The equation of the critical load point is deduced. Design criterion and guideline are given for future designers regarding with the load variation. Equivalent circuit model of the system is built and simulated by Saber. Furthermore, experiment is setup and the results are compared and validated.