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Nine toroidal field (TF) coils have been developed in Japan for the international thermonuclear experimental reactor (ITER). The joint resistance of TF coil should satisfy the requirement of smaller than 3 nano-ohm at 2 T of external magnetic field and 68 kA of transport current. Full-size joint sample (FSJS) tests were performed for joint development and for TF coil manufacture, as part of the process control. 11 FSJS tests are conducted in total. FSJS tests were conducted with assistance from a test faculty in the National Institute for Fusion Science as reported in a previous paper. All FSJS tests successfully satisfied the requirement of resistance less than 3 nΩ at 2 T. Additionally, the TF coil joints are subjected to cyclic electromagnetic force and warm-up/cool-down during the ITER operation. The authors investigated the joint performance for the abovementioned influence. The results showed no degradation in the joint resistance. Thus, the TF joint developed in Japan was qualified successfully. [ABSTRACT FROM AUTHOR]

JAEA has conducted qualification and rationalization activities in Japan since March 2009 in order to rationalize manufacturing procedure of ITER toroidal field coil (TFC) structures. These following activities has been performed: qualification of structural materials and qualification and development of welding procedure according to the JSME code constituted for fusion devices, demonstration of the manufacturing method and procedures through manufacture of 1 m mock-ups and full-scale segments of TFC structure. From results of these activities, JAEA confirmed quality of materials and weld joints of gas tungsten arc welding and gas metal arc welding. In addition, JAEA obtained knowledge of welding deformation of actual TFC structures. This paper describes results of these qualification and development activities for ITER TFC structure. [ABSTRACT FROM PUBLISHER]

HTS cable demonstration project supported by Ministry of Economy, Trade and Industry (METI) and New Energy and Industrial Technology Development Organization (NEDO) has started in Japan. The target of this project is to operate a 66 kV, 200 MVA HTS cable in the live network of Tokyo Electric Power Company in order to demonstrate its reliability and stable operation. The design of the HTS cable with DI-BSCCO has been completed as well as those of a termination and a joint. A 30-meter HTS cable system with terminations, a joint and a cooling system was installed in SEI facility to confirm their design and performance. Various tests as voltage tests, nominal and over current tests, heat cycle tests, heat loss measurements and so on were conducted and it is verified that the cable has good performances as design. This paper describes the design and test results of a 30-meter HTS cable, and discusses required test items of HTS cables. [ABSTRACT FROM AUTHOR]

The mission of the JT-60SA Tokamak, which will be built in Japan, is to contribute to the early realization of fusion energy in support and supplement of the ITER program. The JT-60SA project is part of the broader approach for fusion energy. In 2008, due to a design change of the TF cross section, and following the redefinition of the global JT-60SA features, mechanical analyses were redone. The first 2D and 3D mechanical analyses were performed on the current TF design, providing useful information on the pros and cons of the new design. For the 2D analysis, the critical area of the inner leg cross section in the location of the equatorial plane was meshed to study the effect of in plane loads. The analysis includes checking the peak field applied to the conductors and the stress on each of the components of the winding pack cross section, in particular in the insulation which is a critical component. The stress in winding pack cross section is due to the accumulation of cool down strain, "in plane" Lorentz forces and to the quench pressure. Both magnetic and mechanical analyses are performed with the ANSYS V11.0 code. In this paper, we present the main steps of the 2D and 3D FEM calculations which were developed by CEA and used in the following analyses. Associated statements concerning possible TF design optimization with respect to cost, feasibility or risk are also presented. [ABSTRACT FROM AUTHOR]

As an intense neutron source for the boron neutron capture therapy system, a FFAG storage ring with Energy/emittance Recovery Internal Target (ERIT) has been developed in the Kyoto University Research Reactor Institute (KURRI). In order to develop storage ring for ERIT scheme, the spiral sector and radial sector FFAG rings were designed and compared about performance in ERIT system. The 3-dimensional magnetic fields of these magnets were calculated with the field analysis code, TOSCA. The pole shape of magnet was carefully optimized checking the betatron tune. Tunes were computed by means of tracking simulations in field maps based on TOSCA models. In this paper, the FFAG magnet design for ERIT system and the construction of FFAG ring in KURRI are described. [ABSTRACT FROM AUTHOR]

We analyse the issues of quench propagation in the NbTi Poloidal Field Conductor Insert (PFCI), recently tested at JAEA Naka, Japan. The simulation tools Mithrandir, already validated against data from previous Nb3Sn Insert Coils, and M3, implementing a more detailed thermal-hydraulic description of the CICC cross section, are used. The results of the analysis are reported in the paper and compared with experimental data, with particular attention to NbTi versus Nb3Sn features and to the effects of different model assumptions. [ABSTRACT FROM AUTHOR]

ITER PFCI has been manufactured in the Europe and installed into the ITER Test Facility in Naka, Japan. The conductor is NbTi cable-in-conduit conductor with thick square stainless steel jacket and almost identical with the design of the ITER PF coils. The main objective of this test is the characterization of the conductor and joints at the conditions relevant to the ITER PF coil operation. Intermediate joint is located in the winding at relatively high field to examine its performance. The main items in the PFCI test program are thermo-hydraulic test, DC mode test, cyclic test and pulse mode test. The PFCI and CSMC were successfully cooled down to cryogenic temperature within 450 hours. The test of the PFCI was performed from May to August 2008. The key technology of the installation, the test methods and procedures, and some preliminary results of cool-down are described in this paper. [ABSTRACT FROM AUTHOR]

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. In particular, the whole Toroidal Field magnet system, described in this paper, will be provided to Japan by the EU. All the TF coil main constituents, i.e. conductor, winding pack, joints, casing, current leads, are here presented and discussed as well as the design criteria adopted to fulfil the machine requirements. The results of the analyses performed by the EU and JA to define and assess the TF magnet system conceptual design are reported and commented. Future work plan is also discussed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Since 2003, three years of the current 5-year national project for development of coated conductors using Y-system superconductors have passed and remarkable results have been achieved. In this paper, the current status and future prospects are reviewed. The group of Fujikura and SRL has worked on a long tape with high performance in the PLD-YBCO supercon- ducting tapes on the IBAD-GZO buffered substrates. The highest Ic × L value of the tape is over 50 k Am which is 212 m in length and 245 A of critical current (Ic). Additionally, a 500 m long IBAD-buffered tape with a reasonable in-plane texture was produced using a large scale IBAD apparatus by Fujikura. In the other group, long tape processing has been developed focusing on lowering production cost. An extremely high Ic value of 692 A was obtained in a short sample by the advanced TFA-MOD method on a CeO2 (PLD)/GZO(IBAD)/Hastelloy substrate. In the efforts for the long tape processing, a 25 m long tape with the Ic value of 100 A by a continuous reel-to-reel system and a 40 m long tape with 155 A by a batch system were realized. 100 m class long tapes were also obtained with the MOCVD and PLD-HoBCO processes. Both groups are aiming for 500 m long tapes with the high Ic value of 300 A/cm-w with a production rate of 5 m/h. Furthermore, feasibility studies for applications using coated conductors have already began due to the above mentioned success of long tape production. Several kinds of coils using the long coated conductors such as solenoid and pancake types and spiral shaped conductors for the cable were made. Reasonable high performance results were confirmed in the trials. New approaches on the preliminary studies for the applications of cables, transformers, motors and current limiters etc. are planned in this project. [ABSTRACT FROM AUTHOR]

Development of the SMES using high temperature superconducting (HTS) coil has progressed as a Japanese national project since FY 2004. The objective of the project is to obtain around twice the normal energy density via an HTS-LTS ‘hybrid’ coil system compared to an LTS coil system. The HTS coil is composed of sixteen double-pancake coils and the double-pancake coil is wound with a Bi2212 Rutherford-type cable. The HTS coil is operated at 4.2 K in liquid helium bath with the LTS coil, and operated at maximum field of 8.9 T. Before we made a hybrid coil system, we verified the design issues using HTS experimental coils. In this paper mechanical compression tests, DC operation tests and thermal runaway tests using the experimental coils are discussed. [ABSTRACT FROM AUTHOR]

A high-temperature superconducting dipole floating in the magnetic field of a normal conducting coil has been developed for the Ring Trap (RT)-1 plasma confinement apparatus at the University of Tokyo. The RT-1 device consists of the floating superconducting dipole, a levitation coil made of normal conductor, a vacuum vessel for plasma confinement and detachable services for the floating dipole. This paper describes the design concept and operating scenario of the floating dipole as well as the required services such as a HTS persistent current switch necessary to realize this scenario. [ABSTRACT FROM AUTHOR]

R&D of fundamental technologies for superconducting AC Power equipment (Super-ACE project) started as a national project, for a five-year plan since fiscal 2000 by MIT and NEDO. This project is to research and develop the basic technology of super-conductive cable, fault current limiter and transformer. This paper summarizes the research and development of following 2 types FCL. The R&D of the SN transition resistive type superconducting thin film fault current limiter aims to establish large-current/high-voltage technology by arranging films in multi-parallel/series, and increasing the current-carrying capacity through widening the area of the thin film of the current limiting element. The R&D of the reactor for a rectifier-type fault current limiter using coils of superconducting wire of the Ag sheath Bi2223 tape, aiming to apply it to high-voltage systems. [ABSTRACT FROM AUTHOR]