Support Force Characteristics Analysis of Reluctance-Type Three-Degree-of-Freedom Magnetic Bearing with Multi-Disk

A reluctance-type three-degree-of-freedom magnetic bearing with multi-disk has been developed to improve the high-support force density. The structure of the magnetic bearing does not use permanent magnets to simplify assembly and disassembly while enabling it to be used in special environments with high or cryogenic temperatures. The support force is expected to be reduced compared to structures with permanent magnets, but quantitative comparisons have not been made. Therefore, in this paper, a support force analysis comparison is conducted between the structure with permanent magnets and the proposed structure without permanent magnets. Moreover, design guidelines are clarified through parametric studies of design parameters to achieve the high support force density for the proposed structure. Furthermore, a new energizing method that uses magnetic flux interference is applied to the proposed structure. The analysis results show that at the maximum current, the support force is improved by 15.7% and 43.6% in the axial and radial directions, respectively, compared to the conventional method.