ELECTRIC MACHINE

PROBLEM TO BE SOLVED: To reduce losses in the machine caused by torque ripples generated with unbalanced forces by the presence of stator MMF harmonics.SOLUTION: A permanent magnet machine 10 comprises a stator 12 having: a stator core 18; a plurality of stator teeth 20; and a plurality of stator windings 24 coupled to the stator core. The stator is configured to generate a stator magnetic rotating field when the stator windings are excited with an electric current. The stator magnetic rotating field includes both synchronous sub-harmonic and super-harmonic components. The permanent magnet machine also includes a rotor 14 that is disposed within the stator. The rotor includes a rotor core 26 and a plurality of rotor magnets 32 that are coupled to the rotor core. The rotor magnets are further configured to have a predefined orientation profile such that when the stator windings are excited with an electric current, sub-harmonic and super-harmonic magnetic rotating fields are generated in the rotor magnetic field.