Development of magnetic sensors for JT-60SA

Takechi, Manabu; Matsunaga, Go; Sakurai, Shinji; Sasajima, Tadayuki; Yagyu, Junichi; Hoshi, Ryo*; Kawamata, Yoichi; Kurihara, Kenichi; JT-60SA Team; Nishikawa, T.*; et al.

Fusion Engineering and Design, 96-97, p.985 - 988, 2015/10

https://doi.org/10.1016/j.fusengdes.2015.06.108

Feeder components and instrumentation for the JT-60SA magnet system

Yoshida, Kiyoshi; Kizu, Kaname; Murakami, Haruyuki; Kamiya, Koji; Honda, Atsushi; Onishi, Yoshihiro; Furukawa, Masato; Asakawa, Shuji; Kuramochi, Masaya; Kurihara, Kenichi

Fusion Engineering and Design, 88(9-10), p.1499 - 1504, 2013/10

https://doi.org/10.1016/j.fusengdes.2012.12.010

The modifying of the JT-60U magnet system to the superconducting coils (JT-60SA) is progressing as a satellite facility for ITER by both parties of Japanese government and European commission (EU) in the Broader Approach agreement. The magnet system for JT-60SA consists of 18 Toroidal Field (TF) coils, a Central Solenoid (CS) with 4 modules, and 6 Equilibrium Field (EF) coils. The manufacturing of the JT-60SA magnet system is in progress in EU and Japan. The JT-60SA superconducting magnet system generates an average heat load of 3.2 kW at 4 K to the cryoplant, from nuclear and thermal radiation, conduction and electromagnetic heating, and requires current supplies 20 kA for 4 CS modules and 6 EF coils, 25.7 kA to 18 TF coils. The helium flow to remove this heat, consisting of supercritical helium at pressures up to 0.5 MPa and temperature between 4.4-4.8 K, is distributed to the coils and structures through the valve box (VB) from the cryoline connecting to the auxiliary cold box located outside the torus hall. The feeders also contain the electrical supplies from the current lead transitions to room temperature to the coil. The feeder components consist of the in-cryostat feeders with flexible parts to allow coil operational displacements from the connection pipes out of the cryostat, including S-bend conductor to allow differential thermal contraction and the coil terminal boxes (CTBs) with HIS current leads. A measurement and control system is required to monitor and control these coils and feeders for safety and optimal operational availability. For each coil, both current and supercritical helium are supplied from external systems and are controlled from a central system as part of the regular operation with plasma pulses. Quench detection instruments for superconducting coils, feeders and HTS current leads are provided as a separate, stand alone system.

Break-even plasma test facilities JT-60; The Significance in the history of technology development

Kurihara, Kenichi

Denki Gakkai Kenkyukai Shiryo, Denki Gijutsushi Kenkyukai (HEE-12-016023), p.29 - 33, 2012/09

Breakeven plasma test facilities JT-60, as a large scale electrical device, has been developed in accordance with great technological advances of electrical applications such as power electronics, large energy storage with a motor generator, high power microwaves, high energy neutral beam, etc. JT-60 demonstrated efficient and continuous nuclear fusion reactions as well as a break-even plasma in a tokamak, and opened up the prospect of a fusion power plant in the future. In this article, the significance of JT-60 is considered from the viewpoint of the history of technology development in electrical engineering.

Eddy current-adjusted plasma shape reconstruction by Cauchy condition surface method on QUEST

Nakamura, Kazuo*; Jiang, Y.*; Liu, X.*; Mitarai, Osamu*; Kurihara, Kenichi; Kawamata, Yoichi; Sueoka, Michiharu; Hasegawa, Makoto*; Tokunaga, Kazutoshi*; Zushi, Hideki*; et al.

Fusion Engineering and Design, 86(6-8), p.1080 - 1084, 2011/10

https://doi.org/10.1016/j.fusengdes.2011.04.045

Introduction; Plasma profile control is the key to a fusion reactor

Kurihara, Kenichi

Purazuma, Kaku Yugo Gakkai-Shi, 86(9), p.517 - 518, 2010/09

http://www.jspf.or.jp/Journal/PDF_JSPF/jspf2010_09/jspf2010_09-517.pdf

http://www.jspf.or.jp/Journal/PDF_JSPF/jspf2010_09/jspf2010_09-541.pdf

http://ci.nii.ac.jp/naid/110007730775

While construction of the ITER aiming at full D-T burning has just started in Southern France, activities in DEMO reactor design and fusion nuclear research are now eagerly progressing. The design/manufacturing of the satellite tokamak JT-60SA has been also conducted under the Japan-EU Broader Approach collaboration on fusion research. To attain a steady state, high performance plasma, profile control of plasma current, density, temperature, and toroidal rotation is considered a key issue for a burning high-beta plasma. In Section 1, contents of the following sections are briefly presented as an introduction to this special issue together with difficulties and interest in this research area.

Study of current decay time during disruption in JT-60U tokamak

Shibata, Yoshihide*; Watanabe, Kiyomasa*; Okamoto, Masaaki*; Ono, Noriyasu*; Isayama, Akihiko; Kurihara, Kenichi; Nakano, Tomohide; Oyama, Naoyuki; Kawano, Yasunori; Matsunaga, Go; et al.

Nuclear Fusion, 50(2), p.025015_1 - 025015_7, 2010/01

https://doi.org/10.1088/0029-5515/50/2/025015

no abstracts in English

Status of JT-60SA tokamak under the EU-JA broader approach agreement

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

https://doi.org/10.1016/j.fusengdes.2008.06.047

no abstracts in English

Application study of a plasma shape reproduction system based on the Cauchy-condition surface (CCS) method considering plasma real-time control

Kurihara, Kenichi; Kawamata, Yoichi; Sueoka, Michiharu; Wang, F.*; Nakamura, Kazuo*; Mitarai, Osamu*; Sato, Konosuke*; Zushi, Hideki*; Hanada, Kazuaki*; Sakamoto, Mizuki*; et al.

Kyushu Daigaku Oyo Rikigaku Kenkyujo RIAM Foramu 2008 Koen Yoshi, p.66 - 69, 2008/06

no abstracts in English

Design study of the JT-60SA supervisory control system

Kawamata, Yoichi; Naito, Osamu; Kiyono, Kimihiro; Itami, Kiyoshi; Totsuka, Toshiyuki; Akasaka, Hiromi; Sueoka, Michiharu; Sato, Tomoki; Oshima, Takayuki; Sakata, Shinya; et al.

Fusion Engineering and Design, 83(2-3), p.198 - 201, 2008/04

https://doi.org/10.1016/j.fusengdes.2007.12.014

The design activity of JT-60SA (JT-60 Super Advanced) which is remodeled to a superconducting tokamak device has been starting under the JA-EU collaborative ITER-BA project. For the JT-60SA control system, the existing system should be reused as much as possible from the viewpoint of cost-effectiveness. We have just begun to discuss the configuration of the advanced Supervisory Control System (SVCS) including the following systems: (1) ultimately flexible real-time control system, (2) precise timing system enough to clarify cause and effect, and (3) safety shutdown control system. In this report, we present the design study of the JT-60SA SVCS with focusing on these systems.

Optimization of the viewing chord arrangement of the ITER poloidal polarimeter

Yamaguchi, Taiki; Kawano, Yasunori; Fujieda, Hirobumi; Kurihara, Kenichi; Sugihara, Masayoshi*; Kusama, Yoshinori

Plasma Physics and Controlled Fusion, 50(4), p.045004_1 - 045004_15, 2008/04

https://doi.org/10.1088/0741-3335/50/4/045004

We have studied the viewing chord arrangement of the poloidal polarimeter in the International Thermonuclear Experimental Reactor (ITER). We have optimized the viewing chord arrangement based on the evaluation using a magnetohydrodynamic equilibrium reconstruction code. This reconstruction code has been developed in this study. We have successfully optimized viewing chord arrangements for three equilibria of the ITER operation scenario. The accuracy of the central safety factor within 3% has been achieved in each case. Furthermore, the viewing chord arrangement, which is optimized for the inductive operation scenario II at the start of the burn phase (S2-SOB), has been applied for other equilibria. As the result, the accuracy has not deteriorated drastically compared with the accuracy which is evaluated using the optimized arrangement for each equilibrium. The viewing chord arrangement for S2-SOB is proposed as the most promising candidate of the ITER poloidal polarimeter.