Magneto-mechanical analysis of an axially laminated synchronous reluctance machine

Abstract : The performance of an axially laminated synchronous reluctance motor is calculated by considering the magneto-mechanical interaction on the electrical steel sheets. The elasticity analysis is performed with 2D finite element method for centrifugal force and shrink-fittings in both the stator frame and the rotor shaft. The 2D magnetostatic analysis is formulated with a mixed formulation involving the magnetic field in edge finite elements. The stress distribution and the components of the magnetic field affect locally the magnetic permeability of the electrical steel sheets. Their constitutive laws account for this magneto-mechanical effect with an equivalent stress approach. With a fixed-point method, this non-linear magneto-static problem is solved and the computation of the torque and the magnetic losses is performed in post-processing. Finally, the effect of the mechanical loads can increase the magnetic losses by 4.1 % mainly due to the stator shrink-fittings, whereas the electromagnetic torque only slightly decreases.