Comparison of Rotor Strength of Various Rotor Structures for Ultra-high-speed Permanent Magnet Synchronous Motor

The mechanical reliability of the rotor is the premise of the stable operation of high-speed motors, and for ultra-high-speed permanent magnet synchronous motors (PMSMs), sterner requirements are placed on the mechanical reliability of the rotor. In this paper, the rotor strength of four rotor structures of ultra-high-speed PMSMs are compared. Combining the rotor sleeve materials and the PM mechanical structures, the rotor stresses of the four rotor structures under different influencing factors are compared by 3D finite element method, and the influence of temperature, interference fit and sleeve thickness on the stresses of different rotor structures are summarized. Then, the stresses of the four rotor structures are analyzed under different operating states. Finally, based on the above analysis, some important conclusions are obtained.