Planar stator configurations for axial flux machines

An apparatus, comprising:

• a rotor configured to rotate about an axis of rotation, the rotor including one or more magnets that generate first magnetic flux in an active region;
• a first conductive sheet positioned within the active region so that generation of eddy currents within the first conductive sheet imposes a drag force on the rotor;
• a stator structure including at least a first winding positioned within the active region;
• at least first and second terminals connected to different portions of the first winding so that (A) application of current between the first and second terminals causes the first winding to generate a second magnetic flux in the active region or (B) flux linkage between the first winding and the one or more magnets while the rotor is rotating generates voltage between the first and second terminals;
• at least a first switch configured and arranged to selectively couple one or more circuit components between the first and second terminals, thereby regulating a flow of current through the first winding;
• and
• control circuitry configured to adjust a manner in which the first switch is operated to selectively couple the one or more circuit components between the first and second terminals and thereby selectively supplement or selectively counteract the drag force on the rotor.