Progress in Superconductivity and Cryogenics (한국초전도ㆍ저온공학회논문지)

The Korean Society of Superconductivity and Cryogenics (한국초전도저온학회)
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Numerical analysis about current non-uniformity in superconducting CICC (cable-in-conduit conductor) joint

초전도 관내연선도체 접합부에서의 전류 불균일에 대한 수치적 분석

  • 이상일 (한국과학기술원 원자력및양자공학과) ;
  • 정상권 (한국과학기술원 기계공학과) ;
  • 최성민 (한국과학기술원 원자력및양자공학과) ;
  • 박갑래 (핵융합연구센터)
  • Published : 2007.09.30
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Abstract

This paper presents transport current non-uniformity in a joint for superconducting multistage cable-in-conduit conductor (CICC) and relaxation in the CICC. The joint is considered to have a current loop linked to an external magnetic field so that it becomes an emf voltage source. It is numerically analyzed using an electrical transmission line model. The inductive current in a resistive joint is compared to that of a non-resistive joint when the ramping field is applied vertically to the joints. Regarding the parameter values of the model. a full scale $Nb_3Sn$ CICC and a strand-to-strand (STS) joint for the toroidal field magnet of the KSTAR (Korea Superconducting Tokamak Advanced Research) device are referenced to. It is found that the resistive joint prevents the current from rising too much and enhances decaying the current when the ramping stops. The 'flattop' current is found to be proportional to the ramp rate of the field (dB/dt). The relaxation length, which is defined as the length within which the maximum induced current falls by 1/e. is found to saturate within 0.27m.

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References

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