Magnetic Flux Density Analysis of Cage Induction Motor Considering Magnetic Saturation by Permeance Model

This paper describes a method to analyze harmonic components of the air-gap flux density distribution on 3-phase cage induction motors, considering the influence of circumferential slot arrangement, stator winding pattern and distribution of air-gap permeance by magnetic saturation. The applied method is based on an analytical model of the permeance and the magnetomotive force distributions.The proposed method is applied to the analysis of a cage induction motor at no-load and full-load conditions. As a result, the harmonic components of the air-gap flux density distributions at different driving conditions are shown quantitatively. The proposed method is also confirmed by using the numerical analysis method (finite element method). From the comparison of these calculated results, the proposed method is shown to be appropriate and useful for quantitative estimation of harmonic flux for cage induction motors.