Analysis Of The Characters Of Vertical Oscillations Of A Permanent Magnet Above A HTS Bulk

In this thesis, the dynamic characteristics of a permanent magnet with a load on top of it (PML) free levitating above a high-temperature superconductor (HTS) levitated system (HTS-PML) were studied. A dynamics equations based on the Newton's laws was established to depict the vibration of the free levitating HTS or PML. A model based on the Hikihara—Moon model was built to describe the levitation force with strong flux pinning. The parameters of the model with strong flux pinning have been confirmed by comparing the experiment results and the simulation results. Some crucial parameters in the dynamic equation have been considered based on the relation of the levitated force and the relative velocity at which the high-temperature superconductor approaches or moves away from the permanent magnet. The characteristics of the HTS-PML levitation system was investigated by the model of the dynamics of magnetic levitation composed of the model with strong flux pinning and the dynamic equation. The critical colliding weight of the PML and the critical colliding amplitude of the external force are calculated. The results show:1), With different external oscillation field or oscillation force, different oscillation laws can be given. That is the oscillation may a single periods oscillation, two periods oscillation, three periods oscillation or four periods oscillation, so as to chaos on the different condition.2), The relationship between the critical colliding amplitudes, P, and frequencies, f, of the external force could be summarized by the following law :P=Af~n. Under the same initial conditions, with the increase of the mass of the PML, the critical colliding external force for the collision will augment. At f=5Hz, the critical colliding external force undertakes an approximately linear increase.3), With the increase of the initial levitation height, the weight which the system is able to levitate increases. With the presumption of no collision, the critical colliding mass of the PML is to decrease with the increase of the initial levitation height.4), The jumping rules of the curves of the critical colliding mass of the PML and the colliding minimal time (mass versus time) and those of the curves of the critical colliding amplitude of the external force and the mass of the PML (force versus mass) are similar.To end the thesis, A brief introduction to the industrial application of the model of the dynamics of magnetic levitation has been given.