Load-independent inductive resonant WPT links

This paper presents the conditions and the design equations for obtaining a load-independent regime for an inductive resonant wireless power transfer link implemented through parallel resonators. The cases of a current and a voltage generator are analyzed and the possibility of obtaining a constant output voltage/current by operating at a suitable frequency is discussed. It is shown that in the case of a voltage generator it is not possible to choose the operating frequency so to obtain a constant output voltage, while it is possible to obtain a constant output current. Conversely, in the case of a current source, a load-independent output in terms of either voltage or current can be obtained by properly selecting the operating frequency