3-D Finite Element Analysis of Magnetic Forces on Stator End-Windings of an Induction Machine

This paper aims to analyze the magnetic forces on the stator end-windings of an induction machine at full load by a 3-D time-harmonic finite element analysis. Under the steady-state condition, the radial, circumferential, and axial forces all consist of a constant component and a sinusoidal component with a double-frequency. The analysis shows that the forces on the knuckle part of the upper part of a coil end are larger than on the other parts and that the constant components and the amplitudes of the sinusoidal components of the forces on the same positions of different coil ends in a phase belt are nearly different. Finally, the analysis of stresses indicates that the stresses in a coil end, corresponding to the constant components of the forces, are small.