Advanced Plasma Energy
Advanced Energy Generation Division Advanced Plasma Energy Research Section
Associate Professor : Takashi MINAMI
Assistant Professor : Shinji KOBAYASHI
Our research is aiming at developing advanced plasma control technology for plasma energy application and investigating high temperature plasma physics
Generation of high performance plasmas by development of plasma heating, diagnostic and control technologies for plasma energy application
Our research interests focus on the physics and engineering of the high temperature plasmas for the development of the fusion energy reactor and new windows of the high temperature plasma application. Understanding and control of the heat, particle and momentum transport in plasmas are indispensable to obtain the high performance plasmas. For this sake, optimization of magnetic field configuration, development in the plasma heating and the particle fueling/pumping technologies and control of the boundary plasma conditions are the important key issues to solve the problems. The neutral beam injection based on the high power hydrogen ion sources has been utilized not only for the plasma heating, but also for the active actuator of the momentum and plasma current, which has enabled us to control the plasma transport to a preferable plasma confinement condition. As well as the development in the plasma heating technology, new fueling schemes are developed to extend the operational region toward high density plasma condition.
In such the case, control of the boundary plasma is one of the important subjects not only to obtain the high performance plasmas but also to realize the optimized plasma-material interactions. In order to understand the heat, momentum and particle transport, we are developing plasma diagnostic systems such as an Nd:YAG laser Thomson scattering, a charge-exchange recombination spectroscopy, a beam emission spectroscopy and so on. These studies provide us important information of the spatiotemporal structure of the density, temperature and flow velocity of the high temperature plasmas and these fluctuation components. Recently, we have observed that the optimization of the heating and fueling schemes and the boundary plasma condition has been able to produce the high performance plasmas with the formation of the transport barrier. We are now clarifying the physical mechanism of the transport barrier formation and its relation to the turbulent fluctuations.
Neutral beam injection system for Heliotron J
Neutral beam injection system consists of two tangential neutral beam lines (BL1 and BL2). Each beam line has maximum applied voltage of 30keV and maximum injection power of 0.7MW, respectively.
Expansion of plasma operation range by advanced fueling method
A short-pulsed high intensity gas puffing (HIGP) is successfully applied to NBI plasma in Heliotron J, resulting formation of high density H-mode plasmas with steep density gradient at peripheral region.