3D TA Formulation Modeling of Bent CORC Cables: Influence of Bending Radius on AC Loss Characteristics

High-temperature superconducting (HTS) CORC cables are promising candidates for next-generation high-field fusion and energy-storage magnets because of their compact geometry, mechanical flexibility, and high current-carrying capability. However, when such conductors are bent into coils, the curvature alters the local magnetic-field distribution and may influence the AC losses. This work presents a three-dimensional finite-element model based on the TA formulation to investigate the electromagnetic behavior of CORC cables under controlled bending. Systematic simulations for bending radii between 90 and 192 mm reveal a non-monotonic dependence of AC transport and magnetization losses on curvature. The initial increase arises from curvature-enhanced normal fields, the subsequent dip from interlayer magnetic cancellation, and the final rise from current concentration near the inner arc. Under ramp-current excitation, the peak loss per unit length exhibits a weak sensitivity to bending. These results suggest that CORC cables retain stable electromagnetic performance even in compact coil geometries.