Research on Rotor Structure Safety of High-speed Permanent Magnet Motor

High rotation speed brings challenges for safe and reliable operation of motors. In this paper, an optimization design and analysis method of the high-speed permanent magnet motor rotor system structure is proposed, and the rotor system structure of a certain type of high-speed permanent magnet motor is optimized. Firstly, the method considers the influence of high temperatures and high speeds on the stress distribution in the rotor. The rotor interference is designed and simulated to obtain the influence of the rotor interference on its stress. And then the optimal interference of the rotor is obtained. Based on rotor dynamics and rotor fluid-structure coupling theory, dry and wet modal models of the optimal rotor are established to calculate the critical speed of rotor. Finally, the rotor structure is verified by fatigue analysis and modal tests. The results show that the finite element results are within 5% of the actual error, and the rotor life meets the working requirements.