Effects of spin-up rate on internal resonance in a high-Tc superconducting bearing system

This research investigates transient behaviors of a rotor passing through resonance in a high-Tc superconducting bearing system. Such a low-damping multi-degree-of-freedom system, subjected to nonlinear force, can show complex dynamical behaviors, in which energy transfer occurs between modes through nonlinear coupling. Our numerical and experimental results show that, in a system of a high-Tc superconducting bearing, internal resonance can occur even in transient cases where the rotor passes through resonance. Effects of the internal resonance and also effects of the spin-up rate on the transient dynamics of the rotor have been examined and clarified by changing the period of increasing voltage applied to a D.C. motor for rotating the rotor.