Modeling of lateral force-displacement hysteresis caused by local flux pinning

The permanent magnet and high-T-c superconductor levitation system has a large variety of setups for positioning and scaling. The flux pinning effect of HTSC has the important role to support a permanent magnet as a flux source. As for the HTSC magnetic bearing which includes both linear and rotary systems, it positively applies the effect to guide the levitated body along the zero-gradient direction of the external field. On the other hand, the relation between force and displacement is well known to have hysteretic characteristics for the change of relative position of the permanent magnet and the superconductor, In this paper, the relation of the lateral force and the lateral displacement around the locally pinned flux on the surface of HTSC is investigated experimentally. Moreover a hysteresis model is proposed based on the experimental force and displacement relation.