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Experimental Investigation of an Eddy-Current Bearing

  • Jorgen L. Nikolajsen

Summary

An AC-electromagnetic bearing based on eddy-current repulsion has been built and tested. The bearing was found to be inherently stable and able to provide support in five degrees of freedom, i.e. a short rotor was fully supported by a single bearing without any feedback control. However, with the current design configuration, the load carrying capacity and the stiffness and damping are lower than for the conventional DC-electromagnetic bearing and the power consumption is higher. Experimental confirmation of the inherent bearing stability and the support capabilities was reported in an earlier paper. The current paper reports on the experimental investigation of two additional capabilities, namely motoring and emergency shutdown without catcher bearings. In addition, quantitative experimental results are presented by which the goodness of each of the bearing capabilities can be judged. Based on these results, design modifications are proposed for improving the bearing capabilities.

Keywords

Journal Bearing Magnetic Bearing Emergency Shutdown Bearing Clearance Support Capability 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Eastham, J. F. and Laithwaite, E. R., “Linear Induction Motors as-Electromagnetic Rivers,” Proceedings IEE, 121, 10, (1974), 1099–1108.Google Scholar
  2. 2.
    Jayawant, B. V., “Electromagnetic Levitation and Suspension Techniques,” Edward Arnold, London, 1981.Google Scholar
  3. 3.
    Jayawant, B. V., “Electromagnetic Suspension and Levitation,” IEE Proceedings, 129 A, 8, (1982), 549–581.Google Scholar
  4. 4.
    Nikolajsen, J. L., “An AC-Electromagnetic Bearing for Flywheel Energy Storage in Space,” to be published in NASA CP, Magnetic Suspension Workshop, NASA Langley, Feburary 1988.Google Scholar
  5. 5.
    Nikolajsen, J. L., “A Magnetic Bearing Based on Eddy-Current Repulsion,” NASA CP 2443, Rotordynamic Instability Problems In High Performance Turbomachinery, (1986), 460–465.Google Scholar
  6. 6.
    Bolton, H., “An Electromagnetic Bearing,” IEE CP 120, Linear Electric Machines, London, (1974), 45–50.Google Scholar
  7. 7.
    Iskierka, S., “Influence of Irregularities of Exciting Current Density Distribution on Induction Bearing Work,” Acta Technica Csav, 5, (1984), 572–582.Google Scholar
  8. 8.
    Iskierka, S., “Analysis of an Induction Bearing by the Finite Element Method,” Archiv fur Electrotechnik, 67, (1984), 375–380.CrossRefGoogle Scholar
  9. 9.
    Connor, K. A. and Tichy, J. A., “Analysis of an Eddy-Current Journal Bearing,” ASME Paper 87-Trib-10, (1987).Google Scholar
  10. 10.
    Rhodes, R. G. and Mulhall, B. E., “Magnetic Levitation for Rail Transport,” Clarendon Press, Oxford, 1981.Google Scholar
  11. 11.
    Foner, S. and Schwartz, B. B. (Editors), “Superconducting Machines and Devices,” Chapter 6: Iwasa, Y., “High Speed Magnetically Levitated and Propelled Mass Ground Transportation,” Plenum Press, New York, (1973), 347–399.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • Jorgen L. Nikolajsen
    • 1
  1. 1.Mechanical Engineering DepartmentTexas A&M UniversityCollege StationUSA

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