Fusion Science and Technology / Volume 47 / Number 3 / April 2005 / Pages 339-344
Technical Paper / Fusion Energy - Experimental Devices and Advanced Designs
The WENDELSTEIN 7-X stellarator (W7-X) is the next step device in the stellarator line of IPP and is presently under construction at the Greifswald branch institute. The experiment aims at demonstrating the steady state capability of a stellarator machine at reactor relevant parameters. An important feature of W7-X is the high geometrical accuracy of the magnetic configuration which implies tight tolerances in the construction and assembly phases. The magnetic system consists of 50 non planar and 20 planar superconducting coils. Critical components are the coil support elements connecting the coil to the central mechanical structure and the inter-coil elements connecting the coils one to the other. Efficient thermal insulation of the superconducting coils is achieved by high vacuum and multi-layer insulation. The plasma vessel is composed of 10 half-modules welded together during the assembly phase. A 10 MW ECRH system with CW-capability operation at 140 GHz is required to meet the scientific objective of W7-X.
The paper will report the recent progress on W7-X with particular emphasis on the components where high technology solutions have been applied.