Transient phenomena analysis of a DC -1MV power supply for the ITER NBI

Yamamoto, Masanori; Watanabe, Kazuhiro; Yamanaka, Haruhiko; Takemoto, Jumpei; Yamashita, Yasuo*; Inoue, Takashi

JAEA-Technology 2010-029, 60 Pages, 2010/08

JAEA-Technology-2010-029.pdf:10.49MB

A power supply for the ITER Neutral Beam Injector (NBI) is a DC ultra-high voltage (UHV) power supply to accelerate negative ion beams of 40 A up to an energy of 1 MeV. Japan Atomic Energy Agency as the Japan Domestic Agency for ITER contributes procurement of dc -1 MV main components such as step-up -1 MV transformers rectifiers, a high voltage deck 2, a -1 MV insulating transformer, a transmission line, a surge reduction system and equipments for site test. Design of the surge suppression in the NBI power supply is one of the key issues to obtain the stable injector performance. This report describes the design study using EMTDC code on the surge suppression by optimizing the core snubber and additional elements in the -1 MV power supply. The results show that the input energy from the stray capacitance to the accelerator at the breakdown can be reduced to about 25 J that is smaller than the design criteria of 50 J for the ITER NBI.

-1 MV DC UHV power supply for ITER NBI

Watanabe, Kazuhiro; Yamamoto, Masanori; Takemoto, Jumpei; Yamashita, Yasuo*; Dairaku, Masayuki; Kashiwagi, Mieko; Taniguchi, Masaki; Tobari, Hiroyuki; Umeda, Naotaka; Sakamoto, Keishi; et al.

Proceedings of 22nd IAEA Fusion Energy Conference (FEC 2008) (CD-ROM), 7 Pages, 2008/10

http://www-naweb.iaea.org/napc/physics/FEC/FEC2008/html/node377.htm#78504

The JADA contributes procurement of DC -1 MV ultra-high voltage (UHV) components such as a -1 MV DC generator, a transmission line and a -1 MV insulating transformer. The DC UHV insulation has been carefully analyzed since DC long pulse insulation is quite different from conventional AC insulation. The insulation structure has been designed and the overall dimensions of the DC UHV components have been finalized. The JADA contributes to provide an effective surge suppression system composed of core snubbers and resistors. Input energy into the accelerator from the power supply can be reduced to about 20 J which satisfies the design criteria of the total 50 J at -1 MV breakdown. From these studies, major technical issues were considered and the functional technical specifications of the UHV components have been developed for the procurement by the JADA.

Neutronics analysis of the ITER NB system; Nuclear responses of the components and shutdown dose around the NB injector

Shibata, Keiichiro*; Maki, Koichi*; Inoue, Takashi*; Hanada, Masaya; Okumura, Yoshikazu; Yamashita, Y.*

Fusion Engineering and Design, 51-52, p.357 - 362, 2000/11

https://doi.org/10.1016/S0920-3796(00)00263-5

no abstracts in English

ITER neutral beam injection system; Japanese design proposal

Ohara, Yoshihiro; Tanaka, Shigeru; Akiba, Masato; Araki, Masanori; Fujisawa, Noboru; Hanada, Masaya; Inoue, Takashi; *; Mizuno, Makoto; Okumura, Yoshikazu; et al.

JAERI-M 91-052, 176 Pages, 1991/03

JAERI-M-91-052.pdf:4.07MB

no abstracts in English

Inverter type high voltage DC power supply for negative-ion-based neutral beam injectors

Mizuno, Makoto; Dairaku, Masayuki; Ohara, Yoshihiro; *; Tanaka, Shigeru; *; Watanabe, Kazuhiro; Yamashita, Y.*;

IEEE 13th Symp. on Fusion Engineering, Vol. 1, p.574 - 577, 1989/00

no abstracts in English

Development of dc -1 MV power supply and negative ion beam accelerator for ITER

Watanabe, Kazuhiro; Yamamoto, Masanori; Taniguchi, Masaki; Umeda, Naotaka; Kobayashi, Kaoru; Hanada, Masaya; Kashiwagi, Mieko; Tobari, Hiroyuki; Dairaku, Masayuki; Sakamoto, Keishi; et al.

no journal, , 

Japan Atomic Energy Agency as a Japanese Domestic Agency will procure the high voltage part of the power supply for the ITER neutral beam injector (NBI). Design studies have been performed on high voltage components and a surge suppression system of the -1 MV power supply. It was confirmed by circuit analysis that an input energy from the power supply to the accelerator can be reduced to 20 joule which is smaller than the design criteria of 50 joule at 1 MV breakdowns. Present status of the development on the negative ion accelerators and high voltage bushing will be also reported.

Structural specification of high voltage bushing for the ITER NBI

Tobari, Hiroyuki; Umeda, Naotaka; Watanabe, Kazuhiro; Inoue, Takashi; Sakamoto, Keishi; Yamashita, Yasuo*

no journal, , 

no abstracts in English

Development of water choke model for high-voltage deck of ITER neutral beam

Tsuchida, Kazuki; Watanabe, Kazuhiro; Yamanaka, Haruhiko; Takemoto, Jumpei; Inoue, Takashi; Tanaka, Shigeru*; Yamashita, Yasuo*

no journal, , 

In ITER Neutral Beam (NB) injection system, the negative ion source and the accelerator should be cooled to generate high energy and high power beam for the prolonged operation. Those devices will be settled at high electric potential of -1 MV and an water choke is needed in the cooling water line to insulate the high voltage. The water choke for ITER should meet the following specifications; high water pressure (2 MPa) and high leak current (several ten mA) due to the reduction of resistivity in hot water (65 C), etc. So, we developed a ceramic insulation tube for the water choke of ITER NB system and it's performance was confirmed by mechanical and withstand voltage tests. From the test results, it was confirmed the developed ceramic tube has sufficient performance (110 kV/tube) as a part of ITER water choke. The anti-corrosion and anti-dissolution of the sealing materials in the ceramic tube was also confirmed under the high leak current condition.