China's "artificial sun" realizes for the first time a 100-second long pulsed neutral beam
The reporter learned from the Hefei Institute of Physical Science of the Chinese Academy of Sciences on the 5th that the "Eastern Sun" (EAST) project known as the "Artificial Sun" by the media has made major progress. The Dongfang Superloop neutral beam injection system achieves a 100-second long pulse neutrality. bundle. It is reported that the long-pulsed neutral beam obtained in this round of experiments is the first in China, marking that China has taken a solid step in the field of neutral beam injection heating. According to reports, the NBI of the “Eastern Supercycle†(EAST) auxiliary heating project undertaken by the plasma of the Hefei Institute of Physics, Chinese Academy of Sciences, was successfully implemented on the comprehensive test platform for 100 seconds. The long pulsed hydrogen neutral beam leads to a preliminary verification of the system's long pulse operation capability. The neutral beam injection system is one of the two auxiliary heating systems for the "EAST" auxiliary heating project of the large scientific project funded by the National Development and Reform Commission, which was completely developed by China. The system involves a variety of disciplines such as precision high-current ion source, high vacuum, low temperature engineering, high voltage and isolation technology, remote precise measurement and control, plasma and beam diagnostics. In this round of experiments, the neutral beam injection system team used only 10 days of debugging according to the experimental plan, ie, a long pulsed neutral beam extraction with a beam energy of 30 keV, beam current of 9A, beam power of about 0.3 MW, and pulse width of 100 s. While successfully testing the performance of the MW-class strong current ion source, we also verified that the NBI subsystems have 100-second long pulse capability. At present, the results of this experiment indicate that China's self-developed neutral beam injection heating system with international advanced level has basically overcome major technical difficulties, and laid a solid foundation for the neutral beam injection system in the EAST physics experiment in 2013. The EAST device is the world's first fully superconducting tokamak device designed and developed by China.
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