This paper presents the design and analysis of permanent magnet (PM) thrust bearing made up of three ring pairs for five degrees of freedom of the inner rings (rotor rings). The arrangement pattern of rings in PM bearing is considered in two ways: conventional structure and Halbach structure. The simplified three dimensional (3D) mathematical models employing Coulombian approach and vector method are used to design the bearing. MATLAB codes are written to evaluate the axial force, stiffness and moments in both the structures for five degrees of freedom, thereby the effect of axial, radial and angular displacements of the rotor on the aforementioned characteristics is addressed. The results of the mathematical model are validated by the results of 3D Finite Element Analysis (FEA) and experiments. It is observed that, the conventional structure seems to be more sensitive to the angular displacement, as the percentage decrease in force and stiffness is more with respect to angular displacement than the Halbach structure. The effect of angular displacement of the rotor on the performance of bearing in both the structures is crucial.
2. Guilherme, G. S., R. Andrade, and A. C. Ferreira, "Magnetic bearing sets for a flywheel system," IEEE Trans. on Applied Super Conductivity, Vol. 17, No. 2, 2150-2153, 2007.
doi:10.1109/TASC.2007.899268
3. Jinji, S., R. Yuan, and F. Jiancheng, "Passive axial magnetic bearing with Halbach magnetized array in magnetically suspended control moment gyro application," Journal of Magnetism and Magnetic Materials, Vol. 323, No. 15, 2103-2107, 2011.
doi:10.1016/j.jmmm.2011.02.020
4. Ohji, T., et al., "Conveyance test by oscillation and rotation to a permanent magnet repulsive-type conveyor," IEEE Trans. on Magnetics, Vol. 40, No. 4, 3057-3059, 2004.
doi:10.1109/TMAG.2004.832263
5. Hussien, A., et al., "Application of the repulsive-type magnetic bearing for manufacturing micromass measurement balance equipment," IEEE Trans. on Magnetics, Vol. 41, No. 10, 3802-3804, 2005.
doi:10.1109/TMAG.2005.854929
6. Chen, C., et al., "A magnetic suspension theory and its application to the heart quest ventricular assist device," Artificial Organs, Vol. 26, No. 11, 947-951, 2002.
doi:10.1046/j.1525-1594.2002.07125.x
7. Yoo, S., et al., "Optimal design of non-contact thrust bearing using permanent magnet rings," International Journal of Precision Engineering and Manufacturing, Vol. 12, No. 6, 1009-1014, 2011.
doi:10.1007/s12541-011-0134-4
8. Yonnet, J. P., "Passive magnetic bearings with permanent magnets," IEEE Trans. on Magnetics, Vol. 14, No. 5, 803-805, 1978.
doi:10.1109/TMAG.1978.1060019
9. Yonnet, J. P., "Permanent magnetic bearings and couplings," IEEE Trans. on Magnetics, Vol. 17, No. 1, 1169-1173, 1981.
doi:10.1109/TMAG.1981.1061166
10. Delamare, J., E. Rulliere, and J. P. Yonnet, "Classification and synthesis of permanent magnet bearing configurations," IEEE Trans. on Magnetics, Vol. 31, No. 6, 4190-4192, 1995.
doi:10.1109/20.489922
11. Lang, M., "Fast calculation method for the forces and stiffnesses of permanent-magnet bearings," 8th International Symposium on Magnetic Bearing, 533-537, 2002.
12. Ravaud, R., G. Lemarquand, and V. Lemarquand, "Force and stiffness of passive magnetic bearings using permanent magnets. Part 1: Axial magnetization," IEEE Trans. on Magnetics, Vol. 45, No. 7, 2996-3002, 2009.
doi:10.1109/TMAG.2009.2016088
13. Ravaud, R., G. Lemarquand, and V. Lemarquand, "Force and stiffness of passive magnetic bearings using permanent magnets. Part 2: Radial magnetization," IEEE Trans. on Magnetics , Vol. 45, No. 9, 3334-3342, 2009.
doi:10.1109/TMAG.2009.2025315
14. Ravaud, R. and Halbach, "Halbach structures for permanent magnets bearings," Progress In Electromagnetics Research M, Vol. 14, 263-277, 2010.
doi:10.2528/PIERM10100401
15. Paden, B., N. Groom, and J. Antaki, "Design formulas for permanent-magnet bearings," Journal of Mechanical Design, Vol. 125, 734-739, 2003.
doi:10.1115/1.1625402
16. Samanta, P. and H. Hirani, "Magnetic bearing configurations: Theoretical and experimental studies," IEEE Trans. on Magnetics, Vol. 44, No. 2, 292-300, 2008.
doi:10.1109/TMAG.2007.912854
17. Bekinal, S. I., T. R. Anil, and S. Jana, "Force, moment and stiffness characteristics of permanent magnet bearings," Proceedings of National Symposium on Rotor Dynamics, 161-168, 2011.
18. Bekinal, S. I., T. R. Anil, and S. Jana, "Analysis of axially magnetized permanent magnet bearing characteristics," Progress In Electromagnetics Research B, Vol. 44, 327-343, 2012.
19. Bekinal, S. I., T. R. Anil, and S. Jana, "Analysis of radial magnetized permanent magnet bearing characteristics," Progress In Electromagnetics Research B, Vol. 47, 87-105, 2013.
20. Bekinal, S. I., T. R. Anil, and S. Jana, "Analysis of radial magnetized permanent magnet bearing characteristics for five degrees of freedom," Progress In Electromagnetics Research B, Vol. 52, 307-326, 2013.