Optimization of the skew angle of rotor poles in permanent magnet machines based on the inverse problem method

This paper presents optimization of the skew angle of rotor magnetic poles in permanent magnet brushless DC machines. The skew angle optimization is achieved using the gradient based inverse problem methodology. The paper introduces the armature winding flux linkages and associated induced EMFs for the first time as the object function. Meanwhile, this object function involves the use of stored energy and excitation perturbation techniques. An example 1.2 hp permanent magnet brushless DC machine is used to demonstrate the validity and usefulness of the method.