Zeroth-Mode Vibration Suppression for Surface-Mounted PMSM by Increasing the Axial Spatial Order of Electromagnetic Force

Zeroth-mode vibration is the important noise source in most permanent magnet synchronous machines (PMSMs). In this article, the electromagnetic force and the vibration were studied along different directions, and a new method was proposed to suppress the zeroth-mode vibration for surface-mounted PMSMs (SPMSMs). First, it was found that the vibration response is almost inversely proportional to the fourth power of the axial spatial order of the electromagnetic force harmonic by studying the electromagnetic force and the vibration along different directions. Based on the relationship, a new method is proposed to increase the axial spatial order of the electromagnetic force harmonic for the zeroth-mode vibration suppression. Next, the effect of the proposed method is validated by simulating the electromagnetic performances and the vibrations of three 10-pole/30-slot SPMSMs, whose rotors are designed using different methods. Finally, three prototypes are built to compare the vibration accelerations, and the results prove that the proposed method can suppress the zeroth-mode vibration effectively.