Fundamental studies for the application of quench protection systems based on an active power method for cryocooled LTS coils

Kazuya Takeuchi, Nozomu Nanato, Satoru Murase, Seok Beom Kim, Gen Nishijima, Kazuo Watanabe, Takao Takeuchi, Nobuya Banno, Akihiro Kikuchi

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14 Citations (Scopus)


When the quenching occurs in a superconducting coil, excessive joule heating in normal area may damage the coil. It is necessary to detect quenching in the coil as soon as possible and discharge the magnetic energy stored in the coil. Therefore, we propose a superconducting coil protection system based on an active power method. The system is highly resistant to the noise and does not require cancel voltage taps, so it is useful for both AC and DC coils. We have presented the effectiveness of the system using some test coils cooled in LN2 or LHe. However, we have not discussed the effectiveness of the proposed system for helium-free cryocooled magnets, in which a larger temperature rise occurs after quenching than in liquid-cooled magnets. In this paper, we verify the effectiveness and practicality of the proposed system through coil protection tests for a cryocooled Nb3Al LTS coil.

Original languageEnglish
Pages (from-to)148-153
Number of pages6
Issue number3-4
Publication statusPublished - Mar 1 2008



  • Active power method
  • Cryocooled LTS coil
  • Protection
  • Quench

ASJC Scopus subject areas

  • Materials Science(all)
  • Physics and Astronomy(all)

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