Numerical analysis of magnetic noise and torque ripples of split-phase induction motors

This paper presents a numerical analysis of magnetic noise and torque ripples, caused by radial and tangential magnetic forces respectively, in split-phase induction motors. The computation method is based on a magnetic equivalent circuit (MEC) coupled with an electrical circuit and has been developed in the (frequency, spatial order)-domain, such that the effects of the various factors determining the spectral and space harmonic contents of the forces, viz slotting, saturation, eccentricity, etc., can be investigated. The MEC-based computation method has been applied to a split-phase induction motor and has been compared with finite element time-stepping computations.