Vibration and Noise Analysis and Suppression of High Torque Density Permanent Magnet Motor

Permanent magnet synchronous motors are extensively utilized in the mining sector because of their benefits, including high power density, superior efficiency, and straightforward design [1]. However, while providing high torque density, they also generate vibration and noise. In order to reduce the vibration and noise of high torque density permanent magnet motors, this paper analyzes the vibration and noise of a 72-slot 60-pole spoke-structured permanent magnet synchronous motor used in mining, combined with four stator-side tooth modification technologies, including single-slot, double-slot, right-angle chamfer, and cos-shaped modifications. Using Finite Element Analysis (FEA) for optimization, the waveforms of radial electromagnetic forces are analyzed and predicted to determine the effectiveness of their suppression. The surface vibration velocity is examined through harmonic response analysis to assess whether motor vibrations have been effectively reduced. The underlying reasons and variations in radial electromagnetic forces are further explained based on the harmonics of the air gap magnetic field. Furthermore, the electromagnetic performance of the motor is compared, including torque, torque ripple, and cogging torque. Finally, the impact of each modification method on the motor's vibration response is studied through harmonic response analysis.