Methodology to Evaluate the Mechanical Stress in High-Speed Electric Machines With Buried Magnets

Impact of magnet shape and material on the magnet stress

“…To simplify the material failure analysis, the stress state is mapped to a scalar value so that the Von-Mises stress is [8,25]:…”

“…To simplify the material failure analysis, the stress state is mapped to a scalar value so that the Von‐Mises stress is [8, 25]: $$${\sigma }_{\nu M}=\sqrt{{\sigma }_{xx}^{2}+{\sigma }_{yy}^{2}+{\sigma }_{zz}^{2}-{\sigma }_{x}{\sigma }_{y}-{\sigma }_{x}{\sigma }_{z}-{\sigma }_{y}{\sigma }_{z}+3\left({\tau }_{xy}^{2}+{\tau }_{xz}^{2}+{\tau }_{yz}^{2}\right)}$$$ …”

“…Ponick evaluated the dynamic mechanical stresses and high fatigue resistance of rotors of high-speed motors with V-shaped embedded magnets. The results showed that high dynamic stresses appeared on the bridge of the rotor with alternating stresses up to 300 MPa [8]. Chu et al further investigated the finite element analysis model and the proposed method in a plastic deformation experiment [9].…”