A system for efficiently charging a target device such as a power toothbrush, when placed in a charging receptacle such as a cup connected to a source of electrical power. A plurality of steering coils are arranged around the primary charging coil in the charging receptacle. A control circuit changes the magnetic field phase pattern of the steering coils relative to the phase of magnetic field of the primary coil until the maximum power transfer between the charging receptacle and the target device is determined. Charging of the target device occurs at the maximum power transfer rate.