Quench Detection and Protection for High Temperature Superconducting Transformers by Using the Active Power Method

Nozomu Nanato, Y. Kobayashi

Research output: Contribution to journalConference article

6 Citations (Scopus)


AC high temperature superconducting (HTS) coils have been developed for transformers, motors and so on. Quench detection and protection system are essential for safety operations of the AC HTS facilities. The balance voltage method is universally used for the quench detection and protection, however especially for AC operations, the method has risks in terms of high voltage sparks. Because the method needs a voltage tap soldered to a midpoint of the coil winding and the AC HTS facilities generally operate at high voltages and therefore high voltage sparks may occur at the midpoint with no insulation. We have proposed the active power method for the quench detection and protection. The method requires no voltage tap on the midpoint of the coil winding and therefore it has in-built effectiveness for the AC HTS facilities. In this paper, we show that the method can detect the quench in an HTS transformer and moreover our proposed quench protection circuits which consist of thyristors are simple and useful for the AC HTS facilities.

Original languageEnglish
Pages (from-to)264-267
Number of pages4
JournalPhysics Procedia
Publication statusPublished - Jan 1 2013
Event26th International Symposium on Superconductivity, ISS 2013 - Tokyo, Japan
Duration: Nov 18 2013Nov 20 2013



  • AC voltage
  • active power method
  • HTS transformer
  • quench
  • thyristor

ASJC Scopus subject areas

  • Physics and Astronomy(all)

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