Numerical Study on Screening Current Induced Stress of Dry-Wound HTS Racetrack Coil

This study presents a mechanical stress analysis of a dry-wound high-temperature superconducting (HTS) racetrack coil, focusing on the effects of screening current-induced stress (SCS). A three-dimensional (3D)H-formulation was used to simulate the nonlinear current distribution caused by screening current. A modified method was applied to enforce the total current in the cross-section without having to introduce cross-sectional subdivisions separated by highly resistive layers, as required in conventional models. The coil domain was not divided into subdomains, resulting in a more continuous current distribution. The resulting Lorentz force density was used in a 3D mechanical model with turn-to-turn contact conditions to represent the dry-wound racetrack coil. The analysis showed that screening current caused both the typical expansion of the straight sections and additional tilting def…