Experimental Studies on the Dynamic Responses of Coated Superconductor Stack Levitated Above a Permanent Magnet Guideway

In this work, we experimentally investigated the dynamic responses of stacked coated conductor tapes that were levitated over an Nd-Fe-B magnet guideway. The experiments were carried out on a recently designed test rig that can simultaneously measure the acceleration and levitation force during a vibration process. We applied three typical excitations, viz., unloading, free fall, and pulsed excitation. The attenuation coefficient and damping ratio of such stack-based maglev system were analyzed by means of free vibration attenuation method. Last, the dynamic response of mechanical components of the stack-based maglev on pulsed excitation was visualized clearly. Results obtained by this study tell us that the damping ratio is relative to the intensity of external disturbance, which means a weak excitation will cause a small damping ratio and a longer convergence time; however, a larger damping ratio and a faster convergence of vibration will be presented when a stronger stimulation is imposed on. This phenomenon could be contributed by the metal components of the stack, and is promising in practical application, particularly, in construction of HTS maglev where a large damping ratio is required.