Structural evaluation of the busbar system of Wendelstein 7-X stellarator

Abstract The superconducting magnet system of the Wendelstein 7-X stellarator produces magnetic field up to 3 T at the plasma axis. The system consists of five identical modules, each including ten non-planar and four planar coils as well as a 72° sector of the central supporting ring. The superconducting busbar lines feeding the coils (bus current is up to 18 kA) are routed in a similar way for each module except for the current lead lines and separation planes between adjacent modules. The coils’ modular system allows the design, study and manufacture of the busbar lines independently for each module. The electromagnetic forces experienced by the busbars are taken by the supporting system. The paper presents the current design of the system for the fifth module, main results of the stress analysis and tests.