Koide, Yoshihiko; Yoshida, Kiyoshi; Wanner, M.*; Barabaschi, P.*; Cucchiaro, A.*; Davis, S.*; Decool, P.*; Di Pietro, E.*; Disset, G.*; Genini, L.*; et al.
Nuclear Fusion, 55(8), p.086001_1 - 086001_7, 2015/08
The most distinctive feature of the superconducting magnet system for JT-60SA is the optimized coil structure in terms of the space utilization as well as the highly accurate coil manufacturing, thus meeting the requirements for the steady-state tokamak research: A conceptually new outer inter-coil structure separated from the casing is introduced to the toroidal field coils to realize their slender shape, allowing large-bore diagnostic ports for detailed plasma measurements. A method to minimize the manufacturing error of the equilibrium-field coils has been established, aiming at the precise plasma shape/position control. A compact butt-joint has been successfully developed for the Central Solenoid, which allows an optimized utilization of the limited space for the Central Solenoid to extend the duration of the plasma pulse.
Yoshida, Kiyoshi; Murakami, Haruyuki; Kizu, Kaname; Tsuchiya, Katsuhiko; Kamiya, Koji; Koide, Yoshihiko; Phillips, G.*; Zani, L.*; Wanner, M.*; Barabaschi, P.*; et al.
IEEE Transactions on Applied Superconductivity, 24(3), p.4200806_1 - 4200806_6, 2014/06
The upgrade of the JT-60U magnet system to the superconducting coils (JT-60SA) is progressing as a satellite facility for ITER by Japan and EU in the BA agreement. All components of magnet system are now under manufacturing in mass production. The first superconducting EF conductor was manufactured in 2010 in Japan. First superconducting coil EF4 was manufactured in 2012. Other EF5 and EF6 coils shall be manufactured by 2013 to install temporally on the cryostat base before the assembly of the plasma vacuum vessel. CS model coil is fabricated to qualify all manufacturing process of NbSn conductor. The first TF conductor was manufactured in 2012. The cryogenic requirements for JT-60SA are about 9 kW at 4.5K. Each coil is connected through an in-cryostat feeder to the current leads located outside the cryostat in the CTB. A total of 26 HTS current leads are installed in the CTB. The manufacturing of the magnet system is in progress to provide components to assembly the Tokamak machine.
Yoshida, Kiyoshi; Kizu, Kaname; Tsuchiya, Katsuhiko; Murakami, Haruyuki; Kamiya, Koji; Payrot, M.*; Zani, L.*; Wanner, M.*; Barabaschi, P.*; Heller, R.*; et al.
IEEE Transactions on Applied Superconductivity, 22(3), p.4200304_1 - 4200304_4, 2012/06
The JT-60SA is progressing as a "satellite" facility for ITER in the Broader Approach agreement. The fabrications of the conductor for CS and EF coils were started in 2008. The first superconducting conductor of EF4 coil was manufactured at March 2010. The manufacturing tools for EF coils are design and prepared from 2009. The double pancake using the superconductor has been started at 2011. The TF coil case encloses the winding pack and is the main structural component of the magnet system. The interface between TF case and CS and EF coil were designed. The conductor for TF coils fabrication has been started. The cryogenic system is equivalent to be about 9 kW refrigeration at 4.5 K. Each coil is electrically connected through the in-cryostat feeder and the coil terminal boxes. The 26 current leads using high temperature superconductor. The manufacturing of superconducting magnet for JT-60SA are started by solving its cost and technology.
Matsukawa, Makoto; Kikuchi, Mitsuru; Fujii, Tsuneyuki; Fujita, Takaaki; Hayashi, Takao; Higashijima, Satoru; Hosogane, Nobuyuki; Ikeda, Yoshitaka; Ide, Shunsuke; Ishida, Shinichi; et al.
Fusion Engineering and Design, 83(7-9), p.795 - 803, 2008/12
no abstracts in English
Kizu, Kaname; Tsuchiya, Katsuhiko; Yoshida, Kiyoshi; Edaya, Masahiro; Ichige, Toshikatsu*; Tamai, Hiroshi; Matsukawa, Makoto; della Corte, A.*; Di Zenobio, A.*; Muzzi, L.*; et al.
IEEE Transactions on Applied Superconductivity, 18(2), p.212 - 215, 2008/06
The maximum magnetic field and maximum current of CS and EF coils is 9 T, 20 kA and 6.2 T, 21 kA, respectively. The conductor for CS is NbSn CIC conductor with JK2LB conduit. On the other hand, EF coil conductors are NbTi CIC conductor with SS316LN conduit. In order to reduce the pressure drop and to raise the temperature margin against large AC loss and nuclear heating, central spiral is introduced inside cable. The Tcs margin and stability analyses of the CS and EF coils are performed by using the one-dimensional fluid analysis code with transient heat loads. These coils have enough high Tcs and stability margin against the operational scenario.
Pizzuto, A.*; Semeraro, L.*; Zani, L.*; Bayetti, P.*; Cucchiaro, A.*; Decool, P.*; della Corte, A.*; Di Zenobio, A.*; Dolgetta, N.*; Duchateau, J. L.*; et al.
IEEE Transactions on Applied Superconductivity, 18(2), p.505 - 508, 2008/06
The Broader Approach agreement between Europe and Japan includes the construction of a fully superconducting tokamak, the JT-60 Super Advanced (JT-60SA), as a satellite experiment to ITER. Toroidal field (TF) magnet which consists of 18 D-shaped coils will be provided to Japan by EU. TF coil main constituents are conductor, winding pack, joints, casing and current leads. The design criteria about conductor and structure were discussed between JA and EU adopted to fulfill the machine requirements. The results of the analyses performed by EU and JA to define and assess the TF magnet system conceptual design, are reported and commented.
Tsuchiya, Katsuhiko; Suzuki, Yutaka; Kizu, Kaname; Yoshida, Kiyoshi; Tamai, Hiroshi; Matsukawa, Makoto; Dolgetta, N.*; Portafaix, C.*; Zani, L.*; Pizzuto, A.*
IEEE Transactions on Applied Superconductivity, 18(2), p.208 - 211, 2008/06
Magnet system in JT-60SA consists of 18 toroidal field coils, 7 plasma equilibrium field (EF) coils, and central solenoid (CS) that has 4 modules of solenoids. Mechanical design of EF coils and CS is optimized in order to obtain the broad operational space of plasmas that are double-null plasma with high plasma current for high performance operation and ITER-like configuration with IP=3.5MA for ITER-relevant experiment. In the former design, called NCT, divertor coil (EF4) is made of NbSn conductor, as well as CS conductor. However, it is clear that 6.2T of Bmax is significant to operate ITER-like plasma. Therefore, material of cable for EF4 conductor is changed into NbTi, so that this contributes to cost reduction. Regarding CS design, material of conduit is changed into JK2LB in order to simplify the structure of pre-compression. Stress analysis for support structure and winding pack of EF coils and CS is currently carried out. In the case where the vertical unbalance force of CS is largest in the designed plasma operation, peak stress of conduit is less than fatigue limit in 18,000 cycles that is designed number of plasma shot in JT-60SA. This result shows the recent design of CS conductor has significant mechanical strength.
Yoshida, Kiyoshi; Kizu, Kaname; Tsuchiya, Katsuhiko; Tamai, Hiroshi; Matsukawa, Makoto; Kikuchi, Mitsuru; della Corte, A.*; Muzzi, L.*; Turt, S.*; Di Zenobio, A.*; et al.
IEEE Transactions on Applied Superconductivity, 18(2), p.441 - 446, 2008/06
The upgrade of JT-60U magnet system to superconducting coils (JT-60SA) has been decided by both parties of Japan and EU in the framework of the Broader Approach agreement. The magnet system for JT-60SA consists of 18 toroidal field (TF) coils, a central solenoid (CS) with four modules, seven equilibrium field (EF) coils. TF case encloses the winding pack and is the main structural component. CS consists of four winding pack modules with its pre-load structure. Seven EF coils are attached to the TF coil cases through supports which include flexible plates. Since CS modules are operated at high magnetic field, NbSn superconductor is used. While NbTi superconductor is used in TF coils and EF coils. The magnet system has large heat load from nuclear heating by DD fusion and large AC loss from control actions. This paper descries the technical requirements, the operational interface and the conceptual design of the superconducting magnet system for JT-60SA.
Zani, L.*; Pizzuto, A.*; Semeraro, L.*; Ciazynski, D.*; Cucchiaro, A.*; Decool, P.*; della Corte, A.*; Di Zenobio, A.*; Dolgetta, N.*; Duchateau, J. L.*; et al.
IEEE Transactions on Applied Superconductivity, 18(2), p.216 - 219, 2008/06
The upgrade of JT-60U to JT-60 Super Advanced (JT-60SA), a fully superconducting tokamak, will be performed in the framework of the Broader Approach (BA) agreement between Europe (EU) and Japan. In particular, the Toroidal Field (TF) system, which includes 18 coils, is foreseen to be procured by France, Italy and Germany. This work covers activities from design and manufacturing to shipping to Japan. The present paper is mainly devoted to the analyses that lead to the conductor design and to the technical specifications of the joints for the JT-60SA TF coils. The conductor geometry is described, which is derived from Cable-In-Conduit concept and adapted to the actual JT-60SA tokamak operating conditions, principally the ITER-like scenario. The reported simulations and calculations are particularly dealing with the stability analysis and the power deposition during normal and off-normal conditions (AC losses, nuclear heating). The final conductor solution was selected through a trade-off between scientific approach and industrial technical orientation. Besides, the TF system connections layout is shown, derived from the industrially assessed twin-box concept, together with the associated thermo-hydraulic calculations ensuring a proper temperature margin.
Zanino, R.*; Astrov, M.*; Bagnasco, M.*; Baker, W.*; Bellina, F.*; Ciazynski, D.*; Egorov, S. A.*; Kim, K.*; Kvitkovic, J. L.*; Lacroix, B.*; et al.
IEEE Transactions on Applied Superconductivity, 17(2), p.1353 - 1357, 2007/06
The PFCI will be tested at JAEA Naka, inside the bore of the ITER Central Solenoid Model Coil. The main test program are the DC characterization of the conductor, the measurement of AC losses in conductor, the hydraulic characterization, the stability and the quench propagation, and the effects of cycling electromagnetic load. Based on and in support of this test program, an extensive campaign of predictive analysis has been initiated on a subset of the above-mentioned test program items and the results of the comparison of selected predictions from different laboratories will be presented and discussed. A sudden quench at 5.7-6.2 K and 45 kA is predicted. The computed temperature increase at the winding outlet is about 0.5 K for the pulse. These results will be compared with the experiment and used for an accurate prediction of the PF coil performance.