Plasma and Fusion Research
Volume 3, S1049 (2008)
Regular Articles
- The Graduate University for Advanced Studies, Toki, Gifu 509-5292, Japan
- 1)
- National Institute for Fusion Science, Toki, Gifu 509-5292, Japan
- 2)
- Japan Atomic Energy Agency, 801-1, Mukoyama, Naka 311-0193, Japan
Abstract
Large-current-capacity high-temperature superconducting (HTS) conductors using YBCO tapes are being considered as an option for the LHD-type fusion energy reactor FFHR. The typical operating current, magnetic field, and temperature of such conductors in FFHR are 100 kA, 13 T, and 20 K, respectively. A preliminary design of the HTS conductor has been proposed for the FFHR helical coils. Analyses have been performed on the proposed HTS conductor regarding thermal properties, mechanical structures, AC losses, and quench detection and protection. It is suggested that stainless steel might be a better choice for the outer jacket of the HTS conductor compared to aluminum alloy. Due to increased specific heats of conductor materials at 20 K, HTS magnets are supposed to be operated more stably compared to low-temperature superconducting (LTS) magnets operated at ∼4 K. The required refrigeration power is also reduced. Therefore, using HTS conductors, it is considered to be viable to assemble the continuous helical coils in segments with joints of conductors, as additional heat generation at the joints can be taken care by utilizing the surplus refrigeration power. According to these analyses, HTS conductors seem to be promising for the FFHR coils.
Keywords
LHD, FFHR, fusion reactor, HTS, YBCO, BSCCO, superconductor, stability
Full Text
References
- [1] A. Sagara et al., Fusion Eng. Design 81, 2703 (2006).
- [2] A. Sagara et al., Nucl. Fusion 45, 258 (2005).
- [3] J.R. Hull, Jour. Nucl. Materials 191-194, 520 (1992).
- [4] G. Janeschitz et al., Fus. Eng. Design 81, 2661 (2006).
- [5] P. Komarek, Fus. Eng. Design 81, 2287 (2006).
- [6] W.H. Fietz et al., Fus. Eng. Design 75-79, 105 (2005).
- [7] L. Bromberg et al., Fus. Eng. Design 54, 167 (2001).
- [8] T. Hemmi et al., Annual Report of National Institute for Fusion Science, ISSN 0917-1185, 278 (2007).
- [9] T. Ando et al., presented at SOFE 2005.
- [10] F. Dahlgren et al., Fus. Eng. Design 80, 139 (2006).
- [11] T. Isono et al., Fus. Eng. Design 81, 1257 (2006).
- [12] W Goldacker et al., J. Phys. Conf. Ser. 43, 901 (2006).
- [13] T. Isono et al., IEEE Trans. Appl. Supercond. 13, 1512 (2003).
- [14] K. Takahata et al., Fus. Eng. Design 82, 1487 (2007).
- [15] A. Sagara et al., Fus. Eng. Design 81, 1299 (2006).
- [16] M.N. Wilson, Superconducting Magents, (Clarendon Press, Oxford, 1983) p. 41.
- [17] K. Shikimachi et al., Journal of Physics: Conference Series 43, 547 (2006).
- [18] G. Bansal et al., to be published in IEEE Trans. Appl. Supercond., June (2008).
- [19] K. Kim et al., Supercond. Sci. Technol. 19, R23 (2006).
- [20] H. Hashizume et al., J. Plasma Fusion Res. SERIES 5, 532 (2001).
- [21] G. Bansal et al., to be published in IEEE Trans. Appl. Supercond., June (2008).
This paper may be cited as follows:
Gourab BANSAL, Nagato YANAGI, Tsutomu HEMMI, Kazuya TAKAHATA, Toshiyuki MITO and Akio SAGARA, Plasma Fusion Res. 3, S1049 (2008).