Tsuchiya, Katsuhiko; Kizu, Kaname; Murakami, Haruyuki; Asakawa, Shuji; Kuramochi, Masaya; Yoshida, Kiyoshi; Tomarchio, V.*
IEEE Transactions on Applied Superconductivity, 20(3), p.525 - 529, 2010/06
The programme of constructing JT-60SA device is progressing under the framework of the Broader Approach (BA) agreement decided by Japan (JA) and European Union (EU). The magnet system for JT-60SA consists of 18 toroidal field (TF) coils, a central solenoid (CS) with four modules, six equilibrium field (EF) coils. It is decided in the agreement between JA and EU that the poloidal field magnet system, CS and EF coils, shall be procured by JA. The CS consists of independent winding pack modules, which is hung from the top of the TF coils through its pre-load structure. The six EF coils are attached to the TF coil cases through supports that include flexible plates allowing radial displacements. In the procurement arrangement (PA) for CS and EF coils that was recently agreed by JA and EU, basic mechanical designs of CS and EF coils are prescribed in the basis of structural analysis. The equipment for the mass-production of conductors for CS and EF coils is prepared by JAEA. And JAEA also prepare the equipment for the fabrication of EF coils in the field of JAEA Naka site because these coils have large bores. In this paper, we describe the recent mechanical design of poloidal field coils, and evaluation result for the support structure.
Murakami, Haruyuki; Ichige, Toshikatsu; Kizu, Kaname; Tsuchiya, Katsuhiko; Yoshida, Kiyoshi; Obana, Tetsuhiro*; Hamaguchi, Shinji*; Takahata, Kazuya*; Mito, Toshiyuki*; Imagawa, Shinsaku*
IEEE Transactions on Applied Superconductivity, 20(3), p.512 - 516, 2010/06
JT-60SA magnets system consists of 18 toroidal field (TF) coils, 4 stacks of central solenoid (CS) and 6 plasma equilibrium field (EF) coils. The maximum magnetic field and maximum current of EF coils is 6.2 T and 20 kA, respectively. It has been decided that the NbTi cable-in-conduit (CIC) conductor is applied to EF coil conductors. The performance verification test was conducted by Japan Atomic Energy Agency (JAEA) and National Institute of Fusion Science (NIFS). The critical current measurement of this sample under the condition of coil operation was performed in the previous test. In addition, the quench test is conducted in this time to evaluate the stability margin and the coil behavior during quench. The Minimum Quench Energy of this conductor and the velocity of normal conducting state propagation are described in this paper. We also described the Tcs margin and maximum temperature during the quench evaluated by thermo-fluid analysis based on the quench test.
Kizu, Kaname; Tsuchiya, Katsuhiko; Kashiwa, Yoshitoshi; Murakami, Haruyuki; Yoshida, Kiyoshi
IEEE Transactions on Applied Superconductivity, 20(3), p.538 - 541, 2010/06
The CS and EF coils in JT-60SA are procured by Japan. The conductor for CS is NbSn cable-in-conduit (CIC). On the other hand, EF coil conductors are NbTi CIC conductor. Delivered superconducting cables and jackets are fabricated into CIC conductors at the jacketing facility constructed in the Naka site of JAEA. The length of jacketing facility is about 660 m. The production of superconducting cables and jackets were started from April 2008. Since the superconducting cables and jackets following the specifications were produced well, the mass production was started. In this paper, the design of jacketing line and the first production results of CIC conductor will be described.
Koizumi, Norikiyo; Nakajima, Hideo; Matsui, Kunihiro; Hemmi, Tsutomu; Takano, Katsutoshi; Okuno, Kiyoshi; Hasegawa, Mitsuru*; Kakui, Hideo*; Senda, Ikuo*
IEEE Transactions on Applied Superconductivity, 20(3), p.385 - 388, 2010/06
JAEA, as the JADA, signed PA for 9 ITER TF coil in 2008. The WP of the TF coil consists of seven DPs and each of DPs has a RP. The conductor is inserted in a groove of a RP and CP is welded to fix the conductor. Since flatness of 2 mm is required for a RP after welding of CPs, laser welding will be used. The tight tolerance of the CP, such as 0.3 mm, is necessary. Machining of a CP from a plate is technically promising method to satisfy the required tight tolerance. However, the machining is time consuming, resulting in penalty of high cost. Therefore, the authors study the feasibility of manufacture of a CP by new method to reduce the cost. A straight CP can be fabricated by hot-rolling and cold-drawing with sufficiently high accuracy, such as 0.1 mm. In addition, the curved CP can be obtained by bending this straight CP with the accuracy of 0.3 mm. Thus, it is concluded that the feasibility of manufacture of the straight and curved CPs with high accuracy can be demonstrated. From these results, JAEA begins trial manufacture of the proto RP and CPs from 2009.
Nunoya, Yoshihiko; Hemmi, Tsutomu; Nabara, Yoshihiro; Matsui, Kunihiro; Isono, Takaaki; Takahashi, Yoshikazu; Koizumi, Norikiyo; Okuno, Kiyoshi
IEEE Transactions on Applied Superconductivity, 20(3), p.1443 - 1446, 2010/06
Japan Atomic Energy Agency has developed NbSn strand for the ITER magnet, strand whose critical current density is about 1.4 times as large as that for ITER CS Model Coil. Magnetic field, temperature, and strain dependence on the critical current (Ic) of the strand are measured by the apparatus developed by the authors. Especially strain property is investigated in detail, and it is shown by strain tensor analysis that upper critical field dependence on strain can be naturally formulated by the high order polynomial terms of strain taking into account residual strain due to thermal contraction difference inside of the strand and applied strain externally. Correlation formula among field, temperature, strain and Ic for the strand is discussed and presented. Performance of superconducting cables composed of the developed strand is evaluated using the formula.
Savary, F.*; Bonito Oliva, A.*; Gallix, R.*; Knaster, J.*; Koizumi, Norikiyo; Mitchell, N.*; Nakajima, Hideo; Okuno, Kiyoshi; Sborchia, C.*
IEEE Transactions on Applied Superconductivity, 20(3), p.381 - 384, 2010/06
no abstracts in English
Banno, Nobuya*; Takeuchi, Takao*; Koizumi, Norikiyo; Okuno, Kiyoshi
IEEE Transactions on Applied Superconductivity, 20(3), p.1455 - 1458, 2010/06
no abstracts in English