Plasma and Fusion Research
Volume 7, 2405026 (2012)
Regular Articles
- Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554, Japan
- 1)
- Tohoku University, 6-6-05 Aramaki, Aoba, Sendai 980-8579, Japan
Abstract
The Cable-In-Conduit Conductor (CICC) is the most promising one for large scale fusion magnets. Now it has been adopted as conductors for ITER magnets. Although the conductor has good mechanical strength against large electromagnetic force, the performance is not so good because the Nb3Sn strands are fragile and the critical current density is sensitive to strain. Because the conductor is composed of hundreds or thousands of strands which are twisted and become tangled, the strands experience extra-bending during energizing magnets. It seems so difficult to analyze plastic deformation of the strands of whole conductor. Our approach to calculate it is unique in terms of using structural mechanics called “Beam Model” based on the measured strand traces inside the conduit. The calculated traces provide us the local curvatures of strands under electromagnetic force. This leads to the evaluate the conductor performance such as Ic degradation.
Keywords
cable-in-conduit conductor, Nb3Sn strand, beam model, bending strain analysis, Ic degradation
Full Text
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This paper may be cited as follows:
Tsuyoshi YAGAI and Takataro HAMAJIMA, Plasma Fusion Res. 7, 2405026 (2012).