A Simplified Analytical Approach for NVH Assessment of Permanent Magnet Synchronous Motors

The paper deals with NVH (Noise Vibration and Harshness) analysis of Permanent Magnet Synchronous Electric Motors (PMSMs) for automotive applications. A simplified analytical model is presented and used to simulate the acoustic emission of PMSMs. The simplified model is based on a 2D circular curved beam of generalized cross section. The input radial and tangential electromagnetic force distribution is computed by means of the Maxwell stress tensor. The differential equations describing the vibrational behavior of the curved beam are analytically solved and explicit, closed-form expressions of the vibration and sound pressure levels are derived. The novelty of the presented model relies in the introduction of the lever-arm effect induced by tangential electromagnetic forces in the stator vibration. The developed model is employed to compare different architectures of PMSMs, particularly referring to their NVH performances.