Fast Calculation of Electromagnetic Vibrations Induced by Longitudinally Varying Excitations in Skewed Electrical Machine

This paper studies the accuracy and computation time of longitudinal loading strategy on acoustic noise and vibration radiated by Permanent Magnet Synchronous Machines (PMSM) under Maxwell force excitations in open-circuit condition and on the full speed range. First, the different loading strategies are presented. In particular, the notion of unit wave Frequency Response Function (WFRF) is presented and discussed. Then, different longitudinal loading strategies are tested and compared. Electromagnetic and structural calculations are performed using Manatee software on a 12s10p PMSM. A new method to compute WFRF while including longitudinally varying excitations is presented. Simulation results show that the calculation time can be significantly reduced with minor effect on the accuracy by using the proposed method.