Winding Non-Planar Coils for Stellarators

The Electron Positron Optimized Stellarator (EPOS) project is centered on developing nonplanar coils for plasma confinement. These coils are wound with high-temperature superconducting (HTS) tape, which is fragile and must be wrapped around each coil approximately 220 times. The challenge lies in the fact that every coil has a unique nonplanar geometry, and the tape must be wound precisely and without defects. Manual winding introduces too much error, and achieving the required dense winding by hand is difficult. To address this, we designed a tool and concept to help with this process. The project explored both fully automated and semi-automated approaches, testing numerous concepts over three months. The final solution integrates electrical and mechanical components into a winding system, supplemented with 3D-printed parts tailored to each coil shape. This device is capable of winding non-planar coils, offering a major step forward in making stellarator production more efficient.