Method of making a motor with reduced Cogging torque

A method for adjusting a cogging torque of a permanent magnet motor, the permanent magnet motor comprising:

• a rotor comprising a rotor yoke and a plurality of permanent magnet that are disposed on a side face of the rotor yoke at predetermined intervals such that polarities of the permanent magnets alternate in a circumferential direction of the rotor yoke;
• and
• a stator comprising a stator yoke that is disposed at a distance from the rotor, salient magnetic poles that are disposed on the stator yoke at even intervals with respect to the circumferential direction and that are opposed to the permanent magnets, and three-phase connected armature windings that are concentratedly wound around the respective salient magnetic poles,
• wherein the method comprises steps of:
• disposing the plurality of permanent magnets in reference positions that are located at even intervals with respect to the circumferential direction of the rotor yoke, are equidistant from the central axis with respect to a radial direction, and are equidistant from axial direction ends of the rotor yoke with respect to an axial direction, such that the polarities of the permanent magnets alternate in the circumferential direction;
• and
• moving at least one of the permanent magnets in at least one of the circumferential, radial, and axial directions of the rotor yoke to adjust the cogging torque.