Replacement of conventional bearings by passive magnetic bearings for highspeed applications, in terms of their performance will be effective, if the design is carried out by optimizing the geometrical dimensions in the given control volume. Present work deals with modification and utilization of two-dimensional (2D) analytical equations in optimization of multi rings permanent magnet (PM) thrust bearing configurations. Conventional and rotational magnetized direction (RMD) configurations are selected in optimizing the design variables for maximum bearing characteristics in a given volume with a constant aspect ratio. The design variables chosen for optimization are axial offset of rotor, number of rings, radial air thickness and inner diameter of the rotor and stator PM rings. MATLAB codes for solving 2D equations are developed in optimizing configuration variables. Further, optimized parameter values of the two configurations are compared. Finally, optimized results obtained using 2D and three-dimensional (3D) equations for the conventional configuration with same aspect ratio are compared, and conclusions are presented.
2. Bekinal, S. I., T. R. Anil, S. Jana, S. S. Kulkarni, A. Sawant, N. Patil, and S. Dhond, "Permanent magnet thrust bearing: Theoretical and experimental results," Progress In Electromagnetics Research B, Vol. 56, 269-287, 2013.
3. Ravaud, R. and G. Lemarquand, "Halbach structures for permanent magnets bearings," Progress In Electromagnetic Research M, Vol. 14, 263-277, 2010.
4. Earnshaw, S., "On the nature of the molecular forces which regulate the constitution of the luminiferous ether," Transactions of the Cambridge Philosophical Society, Vol. 7, 97-112, 1842.
5. Sotelo, G. G., 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.
6. Fang, J., Y. Le, J. Sun, and K. Wang, "Analysis and design of passive magnetic bearing and damping system for high-speed compressor," IEEE Trans. Magn., Vol. 48, No. 9, 2528-2537, 2012.
7. Morales, W., R. Fusaro, and A. Kascak, "Permanent magnetic bearing for spacecraft applications," Tribology Transactions, Vol. 46, No. 3, 460-464, 2003.
8. Tian, L.-L., X.-P. Ai, and Y.-Q. Tian, "Analytical model of magnetic force for axial stack permanent-magnet bearings," IEEE Trans. Magn., Vol. 48, No. 10, 2592-2599, 2012.
9. Bekinal, S. I. and S. Jana, "Generalized three-dimensional mathematical models for force and stiffness in axially, radially, and perpendicularly magnetized passive magnetic bearings with `n' number of ring pairs," ASME Journal of Tribology, Vol. 138, No. 3, 031105(1–9), 2016.
10. Moser, R., J. Sandtner, and H. Bleuler, "Optimization of repulsive passive magnetic bearings," IEEE Trans. Magn., Vol. 42, No. 8, 2038-2042, 2006.
11. Yoo, S. Y., et al., "Optimal design of non-contact thrust bearing using permanent magnet rings," Int. Journal of Precision Engg. and Manufacturing, Vol. 12, No. 6, 1009-1014, 2011.
12. Lijesh, K. P. and H. Hirani, "Development of analytical equations for design and optimization of axially polarised radial passive magnetic bearing," ASME Journal of Tribology, Vol. 137, 011103(1–9), 2015.
13. Bekinal, S. I., M. R. Doddamani, and S. Jana, "Optimization of axially magnetised stack structured permanent magnet thrust bearing using three dimensional mathematical model," ASME Journal of Tribology, Vol. 139, No. 3, 031101(1-9), 2017.
14. Beneden, M. V., V. Kluyskens, and B. Dehez, "Optimal sizing and comparison of permanent magnet thrust bearings," IEEE Trans. Magn., Vol. 53, No. 2, 2017.