Analytical Modeling of Rotor Mechanical Stress for IPMSM with Variable V-Shaped Rotor Angles

To identify and mitigate mechanical issues during the design optimization process without relying on heavy simulations, this paper proposes an equivalent centroid-based analytical model for estimating the maximum mechanical stress (MMS) on the rotor of a V-shaped interior permanent magnet synchronous machine (IPMSM). The proposed method utilizes the equivalent centroid approach to first calculate the average bridge stress, followed by the application of a stress concentration factor (SCF) to account for localized stress intensification phenomena associated with potential mechanical failures. To enhance the accuracy of MMS estimation, a more precise SCF model formulated as a function of a V-shaped rotor angle is subsequently developed. Finite element analysis (FEA) confirms that the proposed analytical model offers enhanced accuracy with an error percentage of less than 1.2 percent. Therefore, the analytical model with the modified SCF suggests it to be a reliable and effective tool for measuring PMSM rotor MMS at the bilateral bridge.