Investigation of electromechanical coupling lateral/torsional vibration in a high-speed rotating continuous flexible shaft of PMSM

Abstract The rotor of Permanent Magnet Synchronous Motors (PMSM) is an electromechanical coupled dynamics system. The asymmetrical magnetic field-induced mechanical vibration has important effect on the operation performance of the high speed and high power density PMSM. In this paper, an electromechanical coupled lateral/torsional dynamic model caused by electromagnetic excitation is derived based on a Lagrange–Maxwell approach. The stability of the equilibrium was analyzed using a linearized matrix of the system equation. A stability criteria of coupled torsional-lateral motions was provided, and the influences of the electromagnetic and mechanical parameters on mechanical vibration stability were investigated. Finally, the vibration damping of the electromechanical coupling parameters vibration was explored. These results we represent get us better to understand the nonlinear response of the eccentric PMSM rotor system and are beneficial to control and diagnose the eccentric.