  For an accurate estimation of the AC losses of superconducting triaxial
cables, we present a 2D model capable to provide a global assessment of
multi-layer triaxial cables, validated against the AC-losses on single-phase
cables provided by the VNIIKP Cable Institute. Four models are presented, the
first being a single-phase cable of 50 tapes and the others being three
triaxial cables made of up to 135 coated conductors distributed in up to 9
layers. A systematic study is devised, where the number of layers per phase
increases from 1 to 3, with at least 14 tapes distributed across each layer of
the first (innermost) phase, 15 in the secondary (middle) phase, and 16 in the
third (outermost) phase, respectively. Remarkably, our results reveal that the
simple strategy of considering an unbalanced distribution for the amplitudes of
the applied current, can generally balance the magnetic field between the three
phases even for the bilayer and trilayer cables, resulting in negligible
magnetic leaks in all situations. Besides, our simulations allow to see for the
first time how the transport and magnetization currents distribute across the
thickness of all the superconducting tapes, from which we have found that the
AC-losses of the 2nd phase is generally higher than at the other phases at low
to moderate transport currents Itr < 0.8 Ic. Nevertheless, depending on whether
the Ic of the SC tapes at the 3rd phase layers is lower than the one at the 2nd
phase, the layers at the third phase can exhibit a considerable increment on
the AC losses, as result of the considered magneto angular anisotropy of the
HTS tapes, which lead to intriguing electromagnetic features that suggest a
practical threshold for the applied transport current, being it 0.8 Ic.
Likewise, the relative change in the AC-losses per adding layers, per phase,
and as a function of the applied current is disclosed.
