Noise and Vibration Characteristics of Permanent-Magnet Synchronous Motors Using Electromagnetic and Structural Analyses

This paper provides a detailed finding of the mechanics of vibration in permanent magnet (PM) synchronous motors due to electromagnetic (EM) origins. Several fractional-slot PM topologies are investigated to quantify the vibration phenomenon that is influenced by motor slot/pole and winding configurations. This paper also sorts out the vibration mode order that is responsible for deformation and the resulting excitation frequency. A finite-element-based cosimulation in the EM and structural domain is used to find the radial forces and, hence, the displacement, to quantify the vibration/noise performance of these selected motors. The displacement and frequency are converted to the sound pressure level to show the relative differences in the noise levels among these motor topologies. The selected motors were experimentally tested to verify the theoretical findings.