In one embodiment, a permanent magnet rotor is provided. The permanent magnet rotor includes a shaft comprising an outer diameter, a first hub coupled about the shaft outer diameter, and a first plurality of pole pieces positioned radially about the hub. The rotor further includes a plurality of permanent magnets positioned radially about the hub. The plurality of pole pieces and the plurality of permanent magnets define a rotor outer diameter, and the rotor outer diameter is magnetically isolated from shaft.