Translational levitation of a permanent magnet above the splicing plane of superconducting blocks under zero field cooling and its motion drag

Abstract

Benefited from the combination of Messiner effect and flux pinning, a permanent magnet (PM) can give the self-stable levitation above a bulk superconductor. The phenomenon provides the basic principle of superconductors in wide applications such as HTS maglev trains and superconducting flywheel systems. When the superconductor works under some conditions without the flux pinning (for example zero-field cooling), the PM will show free motion along multi freedoms due to the full diamagnetism of superconductor. This paper investigated the drag characteristics of the PM moved above the diamagnetic plane spliced by superconducting bulks. The spliced diamagnetic plane can get rid of the limitation of the size of the single superconducting bulk, and realize low-drag translational motion levitation in a large area. The article builds a multidimensional levitation force measurement device to measure the vertical force and lateral force of the PM translation when the superconducting plane works at different temperature. It is found that the lateral force distribution in the PM translation shows with alternating peaks and valleys. The increase of the suspending air gap can reduce the lateral force fluctuation and realize low-drag translation. The translational lateral force has the smaller value at the center of a single superconducting block, and can be measured at the level less than 1 mN. The low drag characteristics bring the potential application of superconducting translational levitation in the low gravity ground simulation for attitude and orbit control experiments of satellites.