Advertisement

The Application of High Temperature Superconductors in Brushless Ac Machines

  • David Dew-Hughes
  • Malcolm McCulloch
Chapter

Abstract

The practical application of high temperature superconductors in electrical machines has been impeded in part by the low critical current densities and sensitivity to magnetic field, which is typical of these materials. The situation is exacerbated by the difficulty of fabricating robust and flexible continuous conductor based on HTS; the manufacturing techniques required to overcome these difficulties result in a very expensive product. A final bar to their ready application is the strain-induced degradation, which limits the radius to which a conductor can be bent. The best commercial HTS tapes cannot be bent to radii less that about 100 mm. This inhibits their use in machine windings, except in very large machines, thus ruling out the construction of small experimental prototypes for developmental purposes. Current densities, which approach those typical of low temperature superconductors, i.e. in excess of 1010 Am-2, are achieved only in epitaxial thin films of high temperature superconductors. Bulk materials have critical current densities that are several orders of magnitude below this value. A remarkable exception is the seeded, melt-textured, single domain samples of the rare-earth barium copper oxide (REBCO) 123 phase. These materials contain about 20% of a fine dispersion of the 211 phase, which contributes both to flux pinning, and to mechanical integrity. The best examples of these materials can carry critical current densities of 108 Am-2, at 77K and in magnetic inductions of up to 1 Tesla. These materials can trap inductions of several Tesla at 77K, and may be regarded as rivals permanent magnets. Many interesting and novel applications have been suggested for these materials.

Keywords

High Temperature Superconductor Critical Current Density Induction Motor Liquid Hydrogen Driving Field 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1].
    McCulloch, M.D., Barnes, GJ. and Dew-Hughes, D; ICEM-2000 Proc. Int. Conf. on Electrical Machines Helsinki Univ. Technol, Espoo, Finland (2000) Vol 2 p 812.Google Scholar
  2. [2].
    Kovalev, L.K., Uyushin, K.V., Penkin, V.T., and Kovalev, K.L.; Electrical TechnologyNo.2, 145, (1994).Google Scholar
  3. [3].
    Kovalev, L.K. et al; Superconductivity, research and development 9–10, 69 (1998)Google Scholar
  4. [3a].
    Kovalev JL.K. et al, Materials Science and Engineering B53, 216 (1998)Google Scholar
  5. [3b].
    Kovalev JL.K. et al; IEEE Trans Appl Superconductivty 9 1261 (1999).CrossRefGoogle Scholar
  6. [4].
    Barnes, G.J., McCulloch, M.D. and Dew-Hughes, D.; Superconductor Science andTechnology 12 518 (1999).CrossRefGoogle Scholar
  7. [5].
    Barnes, G.J., Dew-Hughes, D. and McCulloch, M.D.; Superconductor Science andTechnology 13 229 (2000).CrossRefGoogle Scholar
  8. [6].
    Barnes, G.J., McCulloch, M.D. and Dew-Hughes, D.; Superconductor Science andTechnology 13 875 (2000).CrossRefGoogle Scholar
  9. [7].
    Barnes, GJ., McCulloch, VI.D. and Dew-Hughes, D.; Physica C 331 133 (2000).CrossRefGoogle Scholar
  10. [8].
    Márquez, I. et al; IEEE Trans Appl. Superconductivty 9 1249 (1999).Google Scholar
  11. [9].
    Muta, J., Jung, H., Nakamura, T. and Hoshino, T.; Physica C 372– 376 1531 (2002).CrossRefGoogle Scholar
  12. [10].
    Tsuda, VL, Koike, T, Muramatsu, R and Haseyama, S; Advances in Superconductivity XII, T. Yamashita and K. Tanabe (eds) Springer Verlag, Tokyo (2000) pp 818–820.CrossRefGoogle Scholar
  13. [11].
    Cruise, RJ., Vandenbroucke, K., Landy, C.F., Barnes, GJ. and McCulloch, M.D.; Physica C 341–348 2627 (2000).CrossRefGoogle Scholar
  14. [12].
    Barnes, GJ., McCulloch, M.D. and Dew-Hughes, D.; Inst Physics Conf. Series No. 167, IOP Publishing, Bristol (2000) p 1075.Google Scholar
  15. [13].
    Kovalev, L.K., et al, ICECI7, Dew-Hughes, D., Scurlock, R.G. and Watson J.H.P. (Eds) IOP Publishing, Bristol (1998) p 527.Google Scholar
  16. [14].
    Kovalev, L.K. et al, IEEE Trans. Applied Superconductivity 9 1261 (1999).CrossRefGoogle Scholar
  17. [15].
    Kovalev, L.K., et al, Advances in Cryogenic Engineering 45B 1659 (2000).Google Scholar
  18. [16].
    Oswald, B. et al, ICECI7, Dew-Hughes, D., Scurlock, R.G. and Watson J.H.P. (Eds) IOP Publishing, Bristol (1998) p 547.Google Scholar
  19. [17].
    Oswald, B. et al, IEEE Trans. Applied Superconductivity 9 1201 (1999).CrossRefGoogle Scholar
  20. [18].
    Oswald, B., et al, Advances in Cryogenic Engineering 45B 1653 (2000).Google Scholar
  21. [19].
    Oswald, B. et al.; Physica C 372–376 1513 (2002).CrossRefGoogle Scholar
  22. [20].
    Kovalev JL.K., et al, Physica C372–376 1524 (2002).Google Scholar
  23. [21].
    Kovalev, L.K., et al, ICEC17, Dew-Hughes, D., Scurlock, R.G. and Watson J.H.P. (Eds) IOP Publishing, Bristol (1998) p 379.Google Scholar
  24. [22].
    Dew-Hughes, D., et al, Advances in Cryogenic Engineering 45B 1477 (2000).Google Scholar
  25. [23].
    Pohl, H.W. and Malychev, V.M., Hydrogen Energy Progress 10, Block, D.L. and Veziroglu, T.N.(Eds.) International Association for Hydrogen Energy, (1994) p 1969. Details of the cryogenic aircraft can be found in Janes’ All the World’ s Aircraft, 2001 – 02, pages 459 and 462.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • David Dew-Hughes
    • 1
  • Malcolm McCulloch
    • 1
  1. 1.Department of Engineering ScienceOxford UniversityOxfordUK

Personalised recommendations