Analysis of strand positions in CIC conductor

作者：Teshima S; Nakazawa S; Tsuda M^*; Hamajima T; Yagai T; Nunoya Y; Okuno K; Takahata K

来源：Physica C-Superconductivity and Its Applications, 2011, 471(21-22): 1550-1553.

DOI：10.1016/j.physc.2011.05.236

• CIC conductor
• Strand positions
• Strand displacement
• Twist pitch

Information of 3D strand locations in a Cable-in-Conduit (CIC) conductor is necessary for accurate estimation of conductor performance, e.g., AC losses, current distribution or strain effect. However, it is difficult to derive strand positions after compaction, and there have been no analytical methods to accurately estimate strand positions. In our previous work, we measured strand positions in the CIC conductor, whose length is about 1 m, with 81 NbTi strands and it was verified that some strands were displaced from their original positions. In order to estimate strand locations in a long conductor, we developed a method to analyze three dimensional strand positions taking into account the cable deformation caused by compaction. In this method, we use strand positions in only one cross section of conductor and twist pitches of each sub-cable to calculate the center of gravity of each sub-cable. The strand positions are obtained in a manner that the same order sub-cables rotate around the center of gravity of one order higher sub-cable according to a function of the cabling pitch. We derive the twist pitches after compaction by using measured and calculated strand positions. The calculated strand locations by using the derived twist pitches agree well with the measured ones, with errors of about 0.7 mm.

• 出版日期2011-11