KIEE International Transactions on Power Engineering

The Korean Institute of Electrical Engineers (대한전기학회)
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Designs for 25-kA and 40-kA Vapor-Cooled Bi2223/Copper Leads with the Bi2223 Section Operating in the Current-Sharing Mode

  • Lee, Haigun (MIT Francis Bitter Magnet Laboratory (FBML)) ;
  • Kim, Ho-Min (MIT Francis Bitter Magnet Laboratory (FBML)) ;
  • Yukikazu Iwasa (MIT Francis Bitter Magnet Laboratory (FBML)) ;
  • Kim, Keeman (Nuclear Fusion R&D Center, Korea Basic Science Institute (KBSI))
  • Published : 2003.12.01
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Abstract

This paper presents reference designs for vapor-cooled HTS/Copper leads rated at 25 kA and 40 kA and that satisfy a protection criterion. Each HTS section is cooled by the effluent helium vapor boiling from a 4.2-K bath. Each HTS section is based on a design concept in which a short portion of its warm end (77.3 K) operates in the current-sharing mode; such operation results in a considerable saving for HTS materials required in the HTS section. Two designs of "fully superconducting" vapor-cooled HTS sections, one rated at 25 kA and the other at 40 kA are also presented as comparison bases for the new HTS sections. Each warm end of HTS sections is coupled to an optimal vapor-cooled copper lead rated at the same current as that for the HTS section. The extra coolant required at 77.3 K at the coupling station, an optimal length of the copper section will be shorter than that optimized for helium-vapor cooling between 4.2 K and room temperature.mperature.

Keywords

References

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