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The Effect of Transverse Pressure on the Inter-Strand Coupling Loss of Rutherford Type of Cables

  • A. P. Verweij
  • A. den Ouden
  • B. Sachse
  • H. H. J. ten Kate
Part of the An International Cryogenic Materials Conference Publication book series (ACRE, volume 40)

Abstract

In the framework of the LHC magnet development program at CERN, the effect of transverse pressure on the inter-strand coupling loss of Rutherford type of cables has been investigated. For this purpose a special measuring set-up is designed to measure calorimetrically the AC loss of a stack of keystoned cable pieces for an applied transverse pressure of up to 130 MPa. An AC dipole produces a varying magnetic field with a maximum amplitude of 1 T; the stack of cable pieces can be rotated with respect to the AC dipole in order to distinguish the inter-filament coupling loss from the inter-strand coupling loss. Measurements are presented of a NbTi cable with tinned strands as envisaged to be used for the inner layer of the LHC main bending dipoles. The inter-strand coupling loss increases strongly for higher pressures. The contact resistance Rc between crossing strands, as determined using a network model for the cable, varies between about 7 and 1 μΩ for pressures between 5 and 100 MPa respectively. The small Rc value at 100 MPa corresponds well with AC loss measurements on a model magnet in which a similar cable is used.

Keywords

Contact Resistance Coupling Loss Main Cable Wide Side Coupling Current 
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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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • A. P. Verweij
    • 1
    • 2
  • A. den Ouden
    • 1
  • B. Sachse
    • 1
  • H. H. J. ten Kate
    • 1
  1. 1.Applied Superconductivity CentreUniversity of TwenteEnschedeThe Netherlands
  2. 2.CERNGenevaSwitzerland

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