Development of plasma stored energy feedback control and its application to high performance discharges on JT-60U

Oikawa, Toshihiro; Tsuchiya, Katsuhiko; Kurihara, Kenichi; Kawamata, Yoichi; Fukuda, Takeshi*; Fujita, Takaaki; Neyatani, Yuzuru

Fusion Engineering and Design, 70(2), p.175 - 183, 2004/02

https://doi.org/10.1016/j.fusengdes.2003.11.002

The real-time feedback control of the plasma stored energy has been developed for control of the plasma MHD stability in the JT-60U tokamak. The plasma stored energy can be detected with high accuracy in real-time by the function parametrization method for various plasmas available in JT-60U, such as the ohmic plasma, the L-mode, the H-mode, the high poloidal beta mode and the reversed shear mode over a wide range of the plasma parameters. By manipulating the neutral beam injection power, the plasma stored energy has been successfully controlled along the preprogrammed reference waveform. Especially in the reversed shear mode, this feedback control scheme has improved the reproducibility of the formation of the internal transport barrier, and the MHD instability could be suppressed with keeping the normalized beta in the stable region. The D-T equivalent fusion amplification gain of 0.5 was sustained for 0.8 s in a reversed shear plasma by employing this feedback control scheme.

Development of accelerating unit for high beam current

; Toyama, Shinichi; Nomura, Masahiro; Hirano, Koichiro; Yamazaki, Yoshio; Sato, Isamu

JNC TN9400 99-073, 18 Pages, 1999/08

JNC-TN9400-99-073.pdf:0.57MB

A short traveling wave accelerator with a traveling wave resonant ring is proposed for high beam current accelerators (including the linear accelerator, circular accelerator and storage ring). It is a normal conducting accelerator. The CW beam current can be as high as 10A. Such kind of accelerator unit has large beam holes for damping all of the cavity high order modes in order to avoid the resonant buildup of the fields that would cause multibunch instabilities at high currents. It has high efficiency, high power input capability and low K. It is called "single mode" type. Even though beams are accelerated off the crest for phase stability in circular accelerator, the cavities do not need detuning.

Ion heating up to 1 MeV range with higher harmonic ICRF wave on JT-60U

Nemoto, Masahiro; Kusama, Yoshinori; Afanassiev, V. I.*; Hamamatsu, Kiyotaka; Kimura, Haruyuki; Fujii, Tsuneyuki; Moriyama, Shinichi; Saigusa, Mikio

Plasma Physics and Controlled Fusion, 39(10), p.1599 - 1614, 1997/10

https://doi.org/10.1088/0741-3335/39/10/008

no abstracts in English

Irradiation behaviors of nuclear grade graphite in commercial reactor, 2; Thermal and physical properties

;

Journal of Nuclear Science and Technology, 22(3), p.225 - 232, 1985/00

https://doi.org/10.3327/jnst.22.225

no abstracts in English