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Ikeda, Yoshitaka; Hanada, Masaya; Kamada, Masaki; Kobayashi, Kaoru; Umeda, Naotaka; Akino, Noboru; Ebisawa, Noboru; Inoue, Takashi; Honda, Atsushi; Kawai, Mikito; et al.
IEEE Transactions on Plasma Science, 36(4), p.1519 - 1529, 2008/08
Times Cited Count：12 Percentile：41.25(Physics, Fluids & Plasmas)The JT-60SA N-NBI system is required to inject 10 MW for 100 s at 500 keV. Three key issues should be solved for the JT-60SA N-NBI ion source. One is to improve the voltage holding capability. Recent R&D tests suggested that the accelerator with a large area of grids may need a high margin in the design of electric field and a long time for conditioning. The second issue is to reduce the grid power loading. It was found that some beamlets were strongly deflected due to beamlet-beamlet interaction and strike on the grounded grid. The grids are to be designed by taking account of beamlet-beamlet interaction in three-dimensional simulation. Third is to maintain the D- production for 100 s. A simple cooling structure is proposed for the active cooled plasma grid, where a key is the temperature gradient on the plasma grid for uniform D- production. The modified N-NBI ion source will start on JT-60SA in 2015.
Kikuchi, Katsumi; Akino, Noboru; Ebisawa, Noboru; Ikeda, Yoshitaka; Seki, Norikazu*; Takenouchi, Tadashi; Tanai, Yutaka
JAEA-Technology 2008-034, 25 Pages, 2008/04
JAEA-Technology-2008-034.pdf:3.7MB
The control system for auxiliary pumping facility and primary water cooling facility in JT-60 NBI was updated. To realize the cost reduction, the control system with many input and outputs of 2000 was updated by JAEA itself using commercial Programmable Logic Controllers (PLC's). JAEA also made software with 3600 ladder lines by JAEA itself based on commercial basic programs. In addition to the simple replacement of the hardware and software, the function of remote operation has been newly added. At present, the auxiliary pumping facility and the primary water cooling facility have been stably operated without troubles. The remote operation enables to collect the detailed information on the trouble more easily, resulting in a quick countermeasure for the trouble.
Honda, Atsushi; Okano, Fuminori; Oshima, Katsumi; Akino, Noboru; Kikuchi, Katsumi; Tanai, Yutaka; Takenouchi, Tadashi; Numazawa, Susumu*; Ikeda, Yoshitaka
Fusion Engineering and Design, 83(2-3), p.276 - 279, 2008/04
Times Cited Count：11 Percentile：59.16(Nuclear Science & Technology)The control system of the cryogenic facility in the JT-60 NBI system has been renewed by employing the PLC (Programmable Logic Controller) and SCADA (Supervisory Control And Data Acquisition) system. The original control system was constructed about 20 years ago by specifying the DCS (Distributed Control System) computer to deal with 400 feedback loops. Recently, troubles on this control system have increased due to its aged deterioration. To maintain a high reliability of the cryogenic facility, a new control system has been intended with PLC and SCADA system. By optimizing the function blocks and connecting them in the FBD language, the feedback loops in the new control system have been successfully replaced from DCS to PLC without software developer. At present, the new control system has worked well. This is the first application of the marketable PLC to the actual system with feedback loops of 
400 produced by the user itself.
ion beams in the JT-60 negative ion sourceHanada, Masaya; Kamada, Masaki; Akino, Noboru; Ebisawa, Noboru; Honda, Atsushi; Kawai, Mikito; Kazawa, Minoru; Kikuchi, Katsumi; Komata, Masao; Mogaki, Kazuhiko; et al.
Review of Scientific Instruments, 79(2), p.02A519_1 - 02A519_4, 2008/02
Times Cited Count：6 Percentile：32.32(Instruments & Instrumentation)A long pulse production of high-current, high-energy D ion beams was studied in the JT-60U negative ion source that was designed to produce 22 A, 500 keV D ion beams. Prior to the long pulse production, the short pulse beams were produced to examine operational ranges for a stable voltage holding capability and an allowable grid power loading. From a correlation between the voltage holding capability and a light intensity of cathodoluminescence from the insulator made of Fiber Reinforced Plastic insulator, the voltage holding was found to be stable at 
340 kV where the light was sufficiently suppressed. The grid power loading for the long pulse operation was also decreased to the allowable level of 1 MW without a significant reduction of the beam power by tuning the extraction voltage (Vext) and the arc power (Parc). These allow the production of 30 A D ion beams at 340 keV from two ion sources at Vacc = 340 kV. The pulse length was extended step by step, and finally reached up to 21 s, where the beam pulse length was limited by the surface temperature of the beam scraper without water cooling. The D ion beams were neutralized to via a gas cell, resulting in a long pulse injection of 3.2 MW D
beams for 21 s. This is the first long injection of 20 s in a power range of 3 MW.
Ikeda, Yoshitaka; Akino, Noboru; Ebisawa, Noboru; Hanada, Masaya; Inoue, Takashi; Honda, Atsushi; Kamada, Masaki; Kawai, Mikito; Kazawa, Minoru; Kikuchi, Katsumi; et al.
Fusion Engineering and Design, 82(5-14), p.791 - 797, 2007/10
Times Cited Count：22 Percentile：80.64(Nuclear Science & Technology)Modification of JT-60U to a superconducting device (so called JT-60SA) has been planned to contribute to ITER and DEMO. The NBI system is required to inject 34 MW for 100 s. The upgraded NBI system consists of twelve positive ion based NBI (P-NBI) units and one negative ion based NBI (N-NBI) unit. The injection power of the P-NBI units are 2 MW each at 85 keV, and the N-NBI unit will be 10 MW at 500 keV, respectively. On JT-60U, the long pulse operation of 30 s at 2 MW (85 keV) and 20 s at 3.2 MW (320 keV) have been achieved on P-NBI and N-NBI units, respectively. Since the temperature increase of the cooling water in both ion sources is saturated within 20 s, further pulse extension up to 100 s is expected to mainly modify the power supply systems in addition to modification of the N-NBI ion source for high acceleration voltage. The detailed technical design of the NBI system for JT-60SA is presented.
Ikeda, Yoshitaka; Umeda, Naotaka; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Hanada, Masaya; Honda, Atsushi; Inoue, Takashi; Kawai, Mikito; Kazawa, Minoru; et al.
Nuclear Fusion, 46(6), p.S211 - S219, 2006/06
Times Cited Count：59 Percentile：87.2(Physics, Fluids & Plasmas)Recently, the extension of the pulse duration up to 30 sec has been intended to study quasi-steady state plasma on JT-60U N-NBI system. The most serious issue is to reduce the heat load on the grids for long pulse operation. Two modifications have been proposed to reduce the heat load. One is to suppress the beam spread which may be caused by beamlet-beamlet interaction in the multi-aperture grid due to the space charge force. Thin plates were attached on the extraction grid to modify the local electric field. The plate thickness was optimized to steer the beamlet deflection. The other is to reduce the stripping loss, where the electron of the negative ion beam is stripped and accelerated in the ion source and then collides with the grids. The ion source was modified to reduce the pressure in the accelerator column to suppress the beam-ion stripping loss. Up to now, long pulse injection of 17 sec for 1.6 MW and 25 sec for 
1 MW has been obtained by one ion source with these modifications.
Honda, Atsushi; Okano, Fuminori; Oshima, Katsumi; Akino, Noboru; Kikuchi, Katsumi; Tanai, Yutaka; Takenouchi, Tadashi; Numazawa, Susumu*
JAEA-Technology 2006-020, 20 Pages, 2006/03
JAEA-Technology-2006-020.pdf:2.96MB
no abstracts in English
Kikuchi, Katsumi*; Akino, Noboru; Ikeda, Yoshitaka; Oga, Tokumichi; Oshima, Katsumi*; Okano, Fuminori; Takenouchi, Tadashi*; Tanai, Yutaka*; Honda, Atsushi
Heisei-16-Nendo Osaka Daigaku Sogo Gijutsu Kenkyukai Hokokushu (CD-ROM), 4 Pages, 2005/03
no abstracts in English
Kawai, Mikito; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Hanada, Masaya; Honda, Atsushi; Inoue, Takashi; Kazawa, Minoru; Kikuchi, Katsumi*; Kuriyama, Masaaki; et al.
Fusion Science and Technology, 44(2), p.508 - 512, 2003/09
Times Cited Count：5 Percentile：36.81(Nuclear Science & Technology)The negative ion source for negative ion based neutral beam injector(N-NBI) of JT-60U aims at generating a negative ion beam with 500 keV and 22A for 10s. The N-NBI system was completed in 1996, followed by starting the efforts to increase beam power and energy. (1)Spatial non-uniformity of the source plasma causes position-dependent divergence of a beamlet due to mis-matching of local beam perveance. A part of the divergent energetic beams is intercepted by the grids and resultantly produce the excessive heat load of the grids and/or induce the high voltage breakdown. So several techniques to take measures against and to correct the non-uniformity in these sources were implemented. (2)Correction of beamlet deflection by adjusting the electric field at the extraction grids. It improved the beam divergence and then decreased an excessive heat load of a beam limiter by more than 50 %. As a result, the maximum injection power 6.2MW and beam pulse duration 10 seconds were obtaind.
Oga, Tokumichi; Umeda, Naotaka; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Hikida, Shigenori*; Honda, Atsushi; Ito, Takao; Kawai, Mikito; Kazawa, Minoru; et al.
Review of Scientific Instruments, 73(2), p.1058 - 1060, 2002/02
Times Cited Count：12 Percentile：55.3(Instruments & Instrumentation)no abstracts in English
Kuriyama, Masaaki; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Hikida, Shigenori*; Honda, Atsushi; Ito, Takao; Kawai, Mikito; Kazawa, Minoru; Kusaka, Makoto*; et al.
Fusion Engineering and Design, 56-57(Part.A), p.523 - 527, 2001/10
Times Cited Count：6 Percentile：44.09(Nuclear Science & Technology)no abstracts in English
Umeda, Naotaka; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Hikida, Shigenori*; Honda, Atsushi; Ito, Takao; Kawai, Mikito; Kazawa, Minoru; Kusaka, Makoto*; et al.
Fusion Technology, 39(2-Part2), p.1135 - 1139, 2001/03
no abstracts in English
Ohara, Hiroshi; Akino, Noboru; Ebisawa, Noboru; Hikida, Shigenori*; Honda, Atsushi; Ito, Takao; Kawai, Mikito; Kazawa, Minoru; Kusaka, Makoto*; Kuriyama, Masaaki; et al.
Fusion Technology, 39(2-Part2), p.1140 - 1144, 2001/03
no abstracts in English
Ito, Takao; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Honda, Atsushi; Hu, L.*; Kawai, Mikito; Kazawa, Minoru; Kuriyama, Masaaki; Kusaka, Makoto*; et al.
Fusion Engineering and Design, 51-52, p.1039 - 1047, 2000/11
Times Cited Count：15 Percentile：68.65(Nuclear Science & Technology)no abstracts in English
Kuriyama, Masaaki; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Hikida, Shigenori*; Honda, Atsushi; Ito, Takao; Kawai, Mikito; Kazawa, Minoru; Kusaka, Makoto*; et al.
Review of Scientific Instruments, 71(2), p.751 - 754, 2000/02
Times Cited Count：21 Percentile：72.69(Instruments & Instrumentation)no abstracts in English
Numata, Kazuaki; Otani, Seiji; *; *; *; Goto, Tatsuro*
JNC TN8430 2000-001, 23 Pages, 1999/09
JNC-TN8430-2000-001.pdf:0.89MB
None
Hu, L.*; Akino, Noboru; Ebisawa, Noboru; Honda, Atsushi; Ito, Takao; Kawai, Mikito; Kazawa, Minoru; Kuriyama, Masaaki; Kusaka, Makoto*; Mogaki, Kazuhiko; et al.
JAERI-Tech 99-057, 16 Pages, 1999/08
no abstracts in English
Seki, Hiroshi*; Oga, Tokumichi; Akino, Noboru; Tanai, Yutaka*; *; Kuriyama, Masaaki; Ito, Takao; *
KEK Proceedings 99-17 (CD-ROM), 4 Pages, 1999/00
no abstracts in English
Kuriyama, Masaaki; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Hikida, Shigenori*; Honda, Atsushi; Ito, Takao; Kawai, Mikito; Kazawa, Minoru; Kusaka, Makoto*; et al.
Proceedings of the 18th IEEE/NPSS Symposium on Fusion Engineering (SOFE '99), p.133 - 136, 1999/00
no abstracts in English
Akino, Noboru; Kuriyama, Masaaki; Oga, Tokumichi; Seki, Hiroshi*; Tanai, Yutaka*
JAERI-Tech 98-034, 22 Pages, 1998/08
no abstracts in English
