Presentation Information
[WB5-05]Development of a 2D Scanning Approach for Modelling AC Loss in Twisted Stacked-Tape Cables for HTS Fusion Applications
*Alexander Wiseman1, Yueming Sun1, Nick Strickland1, Zhenan Jiang1 (1. Robinson Research Institute (New Zealand))
Keywords:
FEM,Fusion,PIT-VIPER,Magnetization loss,Dynamic loss,H-Φ formulation
Twisted stacked-tape cables (TSTC), such as the PIT-VIPER cable developed by Commonwealth Fusion Systems (CFS), are strong candidates for use in compact HTS fusion magnet designs. Operating in magnetic fields exceeding 20 T at 20 K, a critical concern for these cables is AC loss driven by time-varying magnetic fields and currents, which can significantly impact magnet performance and cooling system design. Finite element method (FEM) simulations are a powerful tool for evaluating these losses, especially when experimental measurements are impractical, costly, or unable to isolate individual loss mechanisms. However, the immense computational demands of 3D models present a major obstacle to simulating AC loss in twisted cables; even a small number of tapes can take days produce a single data point. Full-size cables, containing potentially hundreds of tapes, are unfeasible to model with this approach.
To overcome this limitation, we present the development of a scanning method that can accurately match the loss in 3D models with a small number of 2D simulations. The method integrates the loss over several cable cross-sections, enabling efficient evaluation of AC loss under combined DC transport current and alternating external magnetic fields. A thorough validation of the approach is carried out using a simplified PIT-VIPER cable, with the copper former and jacket excluded. Results are compared to 3D reference models containing up to 80 tapes at a temperature of 20 K, with applied magnetic fields of up to 8 T and varying DC current levels. Simulations are implemented with H-Φ formulation in COMSOL Multiphysics. Finally, the scanning method is used to simulate magnetization and dynamic loss in full-size PIT-VIPER cables composed of up to 400 individually modelled tapes carrying 50 kA under magnetic fields of up to 20 T.
To overcome this limitation, we present the development of a scanning method that can accurately match the loss in 3D models with a small number of 2D simulations. The method integrates the loss over several cable cross-sections, enabling efficient evaluation of AC loss under combined DC transport current and alternating external magnetic fields. A thorough validation of the approach is carried out using a simplified PIT-VIPER cable, with the copper former and jacket excluded. Results are compared to 3D reference models containing up to 80 tapes at a temperature of 20 K, with applied magnetic fields of up to 8 T and varying DC current levels. Simulations are implemented with H-Φ formulation in COMSOL Multiphysics. Finally, the scanning method is used to simulate magnetization and dynamic loss in full-size PIT-VIPER cables composed of up to 400 individually modelled tapes carrying 50 kA under magnetic fields of up to 20 T.