  AC losses in conductor-on-rounded-core (CORC) cables of YBCO high-temperature
superconducting (HTS) tapes are a significant challenge in HTS power
applications. This study employs two finite element analysis (FEA) models to
investigate the contributions from different AC loss components and provide
approaches for reducing AC losses in cables. An FEA model based on T-A formula
treats the cross-section of thin superconducting layers as 1D lines and,
therefore, only can predict the AC loss generated by the perpendicular magnetic
field. In contrast, the model based on H-formulation can be performed on the
actual 2D rectangular cross-section HTS tapes to provide the total AC losses
generated by magnetic fluxes penetrating from both the edges and surfaces of
HTS tapes, although this model requires more computing time and memory. Both 1D
and 2D simulation approaches were employed to offer a comprehensive
understanding of the effects of cable design and operational parameters on the
AC loss components in a 2-layer CORC cable. The research results given in this
paper are therefore not only valuable to suggest strategies for reducing AC
loss in multi-layer cables but also for developing more accurate and effective
methods to calculate AC loss in CORC HTS cables.
