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In this work, semi-analytical models to compute alternating current (AC) power loss in stacks of high-temperature superconductor YBa2Cu3O7-x (or Y-Ba-Cu-O) tapes subjected to a time-varying magnetic field perpendicular to the tapes with zero transport current are developed. Both standard and non-standard arrangements of tapes are considered. The models take into account screening of the interior of a stack and show decreasing dependence of the power loss per tape with . We validate the results by experiments carried out at temperature K under an applied magnetic field with the amplitude of its induction T and frequencies up to 110 Hz. In addition, explicit formula for an error of analytical expressions for the AC loss is derived, which establishes the applicability domain of the models. The approach is extended to compute the AC loss for lower temperatures, larger magnetic fields strengths, and for frequencies up to several kHz. These studies are important for understanding and predicting the AC loss for contemporary motors and generators. As is shown, the AC loss dependence on the arrangement of tapes in the stack can be quite strong, varying by factors up to ~ 200 for temperatures 20–65 K, magnetic fields 2–5 T and frequencies up to 2 kHz .
