Loss Analysis of Induction Motors by Considering Shrink Fitting of Stator Housings

The losses of induction motors are analyzed using the combination of stress and electromagnetic field analyses that consider the effect of shrink fitting of stator housings. In the combined analyses, the variation in the stress effect with the angle between stress and flux vectors are taken into account using an equivalent stress. The calculated losses are compared with measured results in order to confirm the validity. It is revealed that not only the core loss, but also the primary copper loss and eddy current loss of the stator housing, increase by the shrink-fitting stress according to an increase in the reluctivity of the stator core.