SELECTIVE PERMEABILITY ROTOR STRUCTURE FOR INTERIOR PERMANENT MAGNET MACHINE

A radial flux electric motor includes a stator having a radially inner stator surface and stator windings arranged thereon. The motor also includes a rotor mounted inside the stator and configured to rotate relative thereto about an axis. The rotor has a rotor core constructed from a ferromagnetic material having relatively high magnetic permeability and defined by a rotor outer surface establishing an airgap between the rotor and the stator. The rotor also has a plurality of magnetic poles set in the rotor core and configured to generate magnetic flux. The rotor additionally has inserts constructed from a material having relatively low magnetic permeability in at least one geometric direction. Each insert is mechanically fixed to the rotor core to thereby control magnetic flux distribution and minimize flux leakage inside the rotor.