Air-gap induction variation device for rotary or linear electrical machine

摘要

The device uses one or more movable elements, at selected positions within the flux return path of the electrical machine, for varying the magnetic resistance of the flux return path, to adjust the magnetic air-gap induction, without altering the position of the rotor or the stator. Pref. a rotatable cylinder (3) of a paramagnetic or diamagnetic material acts as part of the rotor or stator yoke, containing axially aligned elements (4) of a high permeability material with a width corresponding to the pole division or the tooth spacing.