Modelling of Stress and Deformation of Interior Permanent Magnet Integrated Motor for Ball Mill Considering Rotor Eccentricity

ABSTRACT The interior permanent magnet integrated motor (IPMIM) for ball mill has complex eccentricity problems. In order to solve the difficult problem of calculating the strength and stiffness of IPMIM in eccentric state, a mathematical model under eccentricity was established. Analytical solutions for the rotor stress and deformation were respectively derived for parallel eccentricity, inclined eccentricity, and composite eccentricity. By using the analytical solutions and finite element method, the stress and deformation of the rotor for IPMIM with a power of 210 kW were analysed. The results show that the calculation results obtained by two methods are highly consistent, which proves that the analytical solutions can accurately predict the stress and deformation of the rotor of IPMIM for ball mill. In addition, based on the analytical modelling, the influence of magnetic tensile stress and structural parameters on the rotor stress and deformation were explored, aiming to summarise the variation laws of the stress and deformation of the rotor.