Investigation of AC Losses in the HTS Twisted Stacked-Tape Conductor Cable Using H and T-A Formulation-Based Finite Element Methods

High-temperature superconducting (HTS) twisted stacked-tape conductor-cable in conduit conductors (TSTC-CICC) are critical in superconducting fusion research. The quantification of ac losses in HTS TSTC-CICC is crucial for determining the thermal load and operational stability. However, due to the multilayer stacking characteristics and complex 3-D twisted structures of HTS TSTC-CICC, the process of analyzing the electromagnetic properties and ac losses through numerical methods is time-consuming. To addresses the need for rapid assessment of AC losses in HTS TSTC-CICC cables, this article compares different types of numerical formulations, acceleration strategies, and geometric dimensions on the time and accuracy of ac loss in HTS TSTC-CICC cables. The principles behind the errors among different models are explored based on flux distribution and current distribution characteristics. The results show that when the twist pitch of HTS TSTC-CICC cables is greater than 200 mm, the 2-D numerical model based on the T-A formulation and multiscale acceleration strategies can achieve a good balance between computational time and accuracy. The error between simulation results and experimental data is between 4.3% and 6.2%, which meets the error requirements for evaluation of ac losses. This article provides a technical reference for the rapid evaluation of ac losses in HTS TSTC-CICC cables.