Abstract

Solid rotors are preferred choice of topology for high-speed applications due to their robustness against high centrifugal forces at high speeds, ease of manufacturability, and higher temperature range. However, for peripheral speeds lower than 200 m/s, laminated rotor structure is preferred because of lower eddy current losses resulting in higher efficiency. However, laminated rotors are complex to manufacture, sensitive to temperature and have vibration and mechanical integrity related issues. As a compromise between these two designs in terms of mechanical strength and efficiency, this study investigates a radial flux 2 MW, 15 krpm induction motor rotor core made of thick laminations. The baseline dimensions of the thick-lamination rotor design are calculated using analytical equations considering aspects such as mechanical stresses, rotordynamics, and bearing parameters. Lastly, the lamination to lamination contact behavior under unbalance load is analyzed for a simplified model and their effect on natural frequencies is studied.