Cryogenic commissioning, cool down and first magnet operation of Wendelstein 7-X

26th International Cryogenic Engineering Conference & International Cryogenic Materials Conference 2016

材料科学;物理学

Nagel, M.^1 ; Dhard, C.P.^1 ; Bau, H.^1 ; Bosch, H.-S.^1 ; Meyer, U.^1 ; Raatz, S.^1 ; Risse, K.^1 ; Rummel, T.^1

Max-Planck-Institut für Plasmaphysik, Greifswald, Germany^1

关键词: Cooling circuits;    Cryogenic system;    Fusion experiments;    Helium temperatures;    Plasma operations;    Steady-state operation;    Thermal shields;    WENDELSTEIN 7-X;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/171/1/012050/pdf
DOI  :  10.1088/1757-899X/171/1/012050

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

The construction of the stellarator fusion experiment Wendelstein 7-X (W7-X) was accomplished in 2014. Commissioning of cryogenic system, first cool down of W7-X cryostat and operation of the magnet system was achieved. First plasma operation was accomplished 10thof December 2015. W7-X consists of a magnet system with 70 superconducting coils inside a cryostat. The cold mass of 456 tons is cooled with a helium plant with an equivalent refrigeration power of 7 kW at 4.5 K. The paper presents the commissioning of the cryogenic system, the cool down of the cryostat and first steady state operation with currents up to 12.8 kA. Helium temperatures, mass flow rates and pressure drops inside W7-X cooling circuits are as expected allowing safe magnet operation. Heat loads on the thermal shield and on the superconducting coils are lower than specified for the cryostat design.