Natural frequencies and vibration modes of shafting for high-speed permanent-magnet synchronous machines

For high-speed motor unit, in particular, it is very important to accurately predict natural frequencies and vibration modes of shafting at the design stage so as to minimize the likelihood of failure. Finite element (FE) analysis and experimental measurements are used to establish the natural frequencies and modes of multi-span shafting coupled by flexible coupling, and to assess the influence of leading design parameters of coupling, such as the intermediate shaft length, wall thickness and coupling stiffness.