Magnetization Losses of Transposed Stacked Tape Conductors Under AC Transverse Magnetic Fields

Twisted stacked-tape conductors (TSTC) have emerged as promising candidates for next-generation high-temperature superconducting (HTS) cables, addressing the challenges of high-current and low-loss operation in high-field applications such as fusion magnets and power systems. This paper presents a rigorous electromagnetic analysis of TSTC and STC cables, integrating advanced numerical modeling with experimental validation to address critical challenges in the physical understanding of their superconducting current distribution and AC loss prediction. For this, a magneto-angular anisotropy model tailored to GdBCO tapes is reported, which accurately captures the Jc dependencies on field magnitude and orientation when adequate ansatz for the 3D modelling of the twisted tapes geometry, and no constant in-field direction conditions, are both considered. We validate the model against recent experimental measurements on eight TSTC prototypes, comprising straight and twisted stacks of up to six tapes under sinusoidal magnetic fields (15–100 mT). The simulations achieve deviations of less than 5%, demonstrating exceptional fidelity in predicting magnetization losses and resolving current density distributions across tape thickness. The results highlight the critical role of twisting geometries in reducing magnetization losses while maintaining current-carrying performance, demonstrating the potential of TSTC designs for scalable, low-loss superconducting cables. Furthermore, the developed model provides a robust tool for optimizing conductor architecture, extending from single tapes to multi-tape architectures, and provides critical physical and computational insights into the interplay between geometric design and energy loss mechanisms. These findings establish a robust foundation for optimizing TSTC cables and similar HTS architectures, like the VIPER conductor, advancing their readiness for deployment in fusion energy, power transmission, and large-scale scientific instruments.