A wireless powering device, an energizable load, a wireless system and a method for a wireless energy transfer

A wireless resonant powering device (1) according to the invention comprises a first inductor winding (3), which is arranged to form a transformer (9) with the inductor winding (13) of the energizable load (11). The first inductor winding (3) is arranged to form a resonant circuit (5), which may comprise a suitable plurality of electric capacitances and coils. The components of the resonant circuit (5) are selected such that the magnetic energy received by the inductor winding (13) damps the energy flow in the resonant circuit so that the induced voltage in the inductor winding (13) is substantially constant and is independent of the magnetic coupling between the first inductor winding (3) and the inductor winding 13 at the operating frequency of the driving means (6). The resonant circuit is driven by the driving means (6), comprising a control unit (6c) arranged to induce an alternating voltage between a first semiconductor switch (6a) and a second semiconductor switch (6b). At the output of the transformer (9) an alternating voltage is generated, which is rectified to a DC-voltage by a diode rectifier, filtered by an output capacitance. The resonant circuit (5) is operable on its coupling independent point by the driving means (6). This figure schematically illustrates a situation, where a variable coupling between the first inductor winding (3) and the inductor winding (13) exists. The invention further relates to a wireless inductive powering device, an energizable load, a wireless system and a method for wireless power transfer.