Electromagnetic Force Characteristics of Magnetic Gradient Levitation Systems using Bulk Superconductors

A superconducting magnetic gradient levitation system, which only needs an iron, bulk superconductors and permanent magnets or coils, can realize an interesting levitated transportation system over a relatively long distance because of its simple structure and stable levitation without active control. The system uses superconductors as a field shaping material to form magnetic gradient that can generate stable levitation force acting on the iron. In this paper, three-dimensional numerical analysis of electromagnetic force characteristics in the bulk superconducting magnetic levitation systems is carried out and the results of this analysis are compared with the experiment. From these results we have confirmed that the three-dimensional structure of the magnetic field and the electromagnetic performance of the superconductors strongly influence the characteristics of the electromagnetic force acting on the iron.