Analysis of Hybrid Rotor PM Motor Caused by Atypical Vibration Sources

In this article, the influence of the atypical vibration source on the vibration of the hybrid rotor permanent magnet (HRPM) motor is analyzed. Accurate analysis and comparison of typical and atypical vibration source contributions to vibration are critical. First, the changes in the space-time order of radial forces resulting from the hybrid rotor structure are analyzed. Meanwhile, the total modulated radial force (TMRF) is calculated based on the force modulation effect. Next, a 3-D structural model is developed and verified for accuracy through modal experimentation. Then, the influence of typical and atypical vibration sources on vibration is analyzed, considering the amplitude, order, frequency, and distance from the natural frequency of TMRF. Finally, the vibration of the HRPM motor is predicted using the finite element simulation and experimental verification. Experiment results indicate that multiple additional low-order radial forces are generated due to the hybrid rotor structure. In addition, the contribution of atypical vibration sources to vibration is more significant than that of typical vibration sources in the HRPM motors. Thus, in the process of HRPM motor design, when analyzing its vibration characteristics, the influence of atypical vibration sources on vibration should be fully considered.