Nabara, Yoshihiro; Hemmi, Tsutomu; Kajitani, Hideki; Ozeki, Hidemasa; Suwa, Tomone; Iguchi, Masahide; Nunoya, Yoshihiko; Isono, Takaaki; Matsui, Kunihiro; Koizumi, Norikiyo; et al.
IEEE Transactions on Applied Superconductivity, 24(3), p.6000605_1 - 6000605_5, 2014/06
no abstracts in English
Hemmi, Tsutomu; Matsui, Kunihiro; Kajitani, Hideki; Okuno, Kiyoshi; Koizumi, Norikiyo; Ishimi, Akihiro; Katsuyama, Kozo
IEEE Transactions on Applied Superconductivity, 24(3), p.4802704_1 - 4802704_4, 2014/06
Japan Atomic Energy Agency (JAEA), as Japan Domestic Agency, has responsibility to procure nine ITER Toroidal Field (TF) coils. The TF coil winding consists of a NbSn Cable-In-Conduit conductor, a pair of joints and a He-inlet. The current capacity of 68 kA is required at the magnetic field of 7 T around the He-inlet region in the TF coil winding. During reaction heat-treatment, the compressive residual strain in NbSn cable is induced by the difference in the thermal expansion coefficients between the NbSn cable and stainless steel jacket. The strands bending in the NbSn cable of the He-inlet is anticipated since there is the compressive residual strain and a gap between the NbSn cable and the He-inlet to introduce SHE flow. If the strand is bent, the variation of mechanical behaviors, such as the elongation of He-inlet during the reaction heat-treatment and the thermally induced residual strain on the jacket around the He-inlet, are expected. To investigate the strands bending in the NbSn cable of the He-inlet, the following items are performed; (1) elongation measurement during reaction heat-treatment, (2) residual longitudinal strain measurement using strain gauges by sample cuttings, (3) nondestructive inspection on the cable and strands using high resolution X-ray CT, Detail of test results and investigation of the strands bending in the NbSn cable of the He-inlet are reported and discussed.
Ozeki, Hidemasa; Hamada, Kazuya; Takahashi, Yoshikazu; Nunoya, Yoshihiko; Kawano, Katsumi; Oshikiri, Masayuki; Saito, Toru; Teshima, Osamu*; Matsunami, Masahiro*
IEEE Transactions on Applied Superconductivity, 24(3), p.4800604_1 - 4800604_4, 2014/06
Takahashi, Yoshikazu; Nabara, Yoshihiro; Ozeki, Hidemasa; Hemmi, Tsutomu; Nunoya, Yoshihiko; Isono, Takaaki; Matsui, Kunihiro; Kawano, Katsumi; Oshikiri, Masayuki; Uno, Yasuhiro; et al.
IEEE Transactions on Applied Superconductivity, 24(3), p.4802404_1 - 4802404_4, 2014/06
Japan Atomic Energy Agency (JAEA) is procuring all amounts of NbSn conductors for Central Solenoid (CS) in the ITER project. Before start of mass-productions, the conductor should be tested to confirm superconducting performance in the SULTAN facility, Switzerland. The original design of cabling twist pitches is 45-85-145-250-450 mm, called normal twist pitch (NTP). The test results of the conductors with NTP was that current shearing temperature (Tcs) is decreasing due to electro-magnetic (EM) load cycles. On the other hand, the results of the conductors with short twist pitches (STP) of 25-45-80-150-450 mm show that the Tcs is stabilized during EM load cyclic tests. Because the conductors with STP have smaller void fraction, higher compaction ratio during cabling is required and possibility of damage on strands increases. The technology for the cables with STP was developed in Japanese cabling suppliers. The several key technologies will be described in this paper.
Iguchi, Masahide; Morimoto, Masaaki; Chida, Yutaka*; Hemmi, Tsutomu; Nakajima, Hideo; Nakahira, Masataka; Koizumi, Norikiyo; Yamamoto, Akio*; Miyake, Takashi*; Sawa, Naoki*
IEEE Transactions on Applied Superconductivity, 24(3), p.3801004_1 - 3801004_4, 2014/06
no abstracts in English
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.
Murakami, Haruyuki; Kizu, Kaname; Tsuchiya, Katsuhiko; Koide, Yoshihiko; Yoshida, Kiyoshi; Obana, Tetsuhiro*; Takahata, Kazuya*; Hamaguchi, Shinji*; Chikaraishi, Hirotaka*; Natsume, Kyohei*; et al.
IEEE Transactions on Applied Superconductivity, 24(3), p.4200205_1 - 4200205_5, 2014/06
Central Solenoid (CS) of JT-60SA are designed with the NbSn cable in conduit conductor. CS model coil (CSMC) was manufactured by using the real manufacturing jigs and procedure to validate the CS manufacturing processes before starting mass production. The dimensions of the CSMC are the same as real quad-pancake. The cold test of the CSMC was performed and the test results satisfied the design requirements. These results indicate that the manufacturing processes of the JT-60SA CS has been established. In this paper, the development and the validation of the CS manufacturing processes are described.
Takao, Tomoaki*; Kawahara, Yuzuru*; Nakamura, Kazuya*; Yamamoto, Yusuke*; Yagai, Tsuyoshi*; Murakami, Haruyuki; Yoshida, Kiyoshi; Natsume, Kyohei*; Hamaguchi, Shinji*; Obana, Tetsuhiro*; et al.
IEEE Transactions on Applied Superconductivity, 24(3), p.4800804_1 - 4800804_4, 2014/06
no abstracts in English
Tani, Norio; Takayanagi, Tomohiro; Ueno, Tomoaki; Harada, Hiroyuki; Saha, P. K.; Togashi, Tomohito; Horino, Koki; Hayashi, Naoki
IEEE Transactions on Applied Superconductivity, 24(3), p.0504004_1 - 0504004_4, 2014/06
J-PARC RCS has two functions as a proton beam driver to the spallation neutron source at MLF and also as an injector to MR. However the required beam parameters for each facility are different. The pulse steering magnet (PSTR) was developed to satisfy these requirements by switching the painting area in each acceleration cycle of MLF and MR and to realize center injection at 400 MeV. Therefore there are two operation modes, painting injection and center injection, for operation of PSTR. Painting injection switches beam size (emittance) between MR and MLF and center injection sets injected beam in the same phase space position. The former is operated with pulse mode of trapezoid current pattern and the latter is realized in DC mode. The magnet field measurement was also performed with two operation modes. In this paper we will report the result of the field measurement of PSTR.
Takayanagi, Tomohiro; Ueno, Tomoaki; Horino, Koki; Togashi, Tomohito; Hayashi, Naoki; Kinsho, Michikazu; Irie, Yoshiro*
IEEE Transactions on Applied Superconductivity, 24(3), p.3800905_1 - 3800905_5, 2014/06
Each pulse power supply of the bending magnets at the J-PARC 3-GeV RCS injection area has been designed and manufactured for the painting injection in the transverse plane. The shift bump and pulse steering magnets generate a trapezoidal waveform, the flat-top part of which is used for beam injection. The horizontal and vertical painting bump magnets dynamically change the beam orbit using a decaying waveform. The PFN switching capacitor system does not produce a current ripple at the flat top, although the IGBT chopping system cannot be free from ripple generation due to switching. However, the IGBT chopping system has an advantage of producing an arbitrary wave pattern as required. This paper summarizes the comparison of both power supply system from view point of the circuit structure, the switching noise and the control of the wave pattern formation.
Takayanagi, Tomohiro; Hayashi, Naoki; Kinsho, Michikazu; Ueno, Tomoaki; Togashi, Tomohito; Horino, Koki; Irie, Yoshiro*
IEEE Transactions on Applied Superconductivity, 24(3), p.0503504_1 - 0503504_4, 2014/06
New power supply of the injection shift bump magnet at the J-PARC 3-GeV RCS has been designed with the energy upgrading of LINAC to 400 MeV. The power supply is required to output the maximum current of 32 kA, which is 1.6 times the present current. Moreover, both current ripple noise and deviation should be less than 0.2% in a range from 10 kA to 32 kA output current. The IGBT chopping system as in the present power supply occurs the continuous current ripple due to the switching. So the circuit structure of the power supply has been changed from the IGBT chopping system to the PFN system by switching the capacitors. The power panel is comprised of 16 banks, each of which outputs 2 kA at 14 kV at maximum. More than four banks have been manufactured and the characteristics were evaluated in the factory. This paper summarizes the design and the experimental results of the new power supply.
Maistrello, A.*; Gaio, E.*; Ferro, A.*; Perna, M.*; Panizza, C.*; Soso, F.*; Novello, L.*; Matsukawa, Makoto; Yamauchi, Kunihito
IEEE Transactions on Applied Superconductivity, 24(3), p.3801505_1 - 3801505_5, 2014/06