Development of low-AC-loss Bi-2223 superconducting multifilamentary wires

Kazuo Funaki, Yuji Sasasige, Haruo Yanagida, Satoshi Yamasaki, Masataka Iwakuma, Naoki Ayai, Tomonobu Ishida, Yusuke Fukumoto, Hiroki Kamijo

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We have been designing and developing advanced Ag-sheathed Bi-2223 multifilamentary wires for the future applications to superconducting transformers of electric rolling stocks. Trial wires were twisted without remarkable degradation in the transport property for suppressing AC losses in a perpendicular magnetic field configuration. The AC losses were measured by a saddle-shaped pickup coil in a wide range of frequency up to a commercial frequency. The experimental results show that the AC loss per cycle has linear frequency dependence in a region of the practical amplitude of AC magnetic field for the transformers, where the excess loss may come from an electromagnetic coupling between the filaments. The hysteresis loss evaluated as a low frequency limit of the AC loss was also reduced with the decrease in the twist pitch, which may be considered as a similar effect to the so-called "twist effect" observed in in- situ Nb3Sn wires.

Original languageEnglish
Article number5153246
Pages (from-to)3053-3056
Number of pages4
JournalIEEE Transactions on Applied Superconductivity
Issue number3
Publication statusPublished - Jun 1 2009


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Cite this

Funaki, K., Sasasige, Y., Yanagida, H., Yamasaki, S., Iwakuma, M., Ayai, N., ... Kamijo, H. (2009). Development of low-AC-loss Bi-2223 superconducting multifilamentary wires. IEEE Transactions on Applied Superconductivity, 19(3), 3053-3056. [5153246].