Study of the multi-driver decoupling model of RF negative ion sources

8 Sep 2020, 02:00
2h
Poster Fundamental processes and modelling P2

Speakers

Ms Na Wang (a) Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; b) University of Science and Technology of China, Hefei 230026, China) Dr Zhimin Liu (a) Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; b) University of Science and Technology of China, Hefei 230026, China) Dr Yahong Xie (a) Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; b) University of Science and Technology of China, Hefei 230026, China)

Description

According to the latest physics design of the China Fusion Engineering Test Reactor (CFETR), radio-frequency(RF) driven negative ion sources are selected as the preferred ion source for CFETR neutral beam injector (NBI).To solve the key problems of the CFETR, the engineering design, development, and construction of the Comprehensive Research Facility for Fusion Technology (CRAFT) has begun. Since the RF driven negative ion sources of CRAFT are Large-area high-current extraction beam sources, according to the NBI beam line extraction surface requirements, the RF negative ion sources will adopt the working mode of multi-driver distributed driving. When multiple RF drivers of the same type work at the same time, there may be mutual coupling and interference between them, which results in an asymmetric distribution of the RF magnetic field in the driver, thereby affects the extraction of ion current of the RF negative ion sources. This study analyzes the multi-driver decoupling model of the RF ion negative sources by simulating the mutual coupling of drivers in different distribution modes and obtains the distribution mode with the least mutual coupling and interference between the driver. In this mode, through simulating decoupling effects of adding metal shielding on the periphery of the driver, adding decoupling circuit in the driver circuit, replacing multiple drivers with larger drivers and so on, the best method of eliminating the coupling interference between the RF negative ion sources drivers is obtained, which provides theoretical support for CRAFT's RF negative ion sources to achieve stable operation of the extracted ion current.

Primary authors

Ms Na Wang (a) Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; b) University of Science and Technology of China, Hefei 230026, China) Dr Zhimin Liu (a) Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; b) University of Science and Technology of China, Hefei 230026, China) Dr Yahong Xie (a) Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; b) University of Science and Technology of China, Hefei 230026, China)

Presentation Materials

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