AC loss in stacks of Y–Ba–Cu–O tapes accounting for side penetration of external magnetic field

A semi-analytical model that accounts for side penetration of a time-varying external magnetic field inside regions between superconducting (SC) layers is proposed for computing the alternating current (AC) power loss in a stack of N superconducting YBa2Cu3O7−x (or Y–Ba–Cu–O) tapes with zero transport current. The N dependence of the AC power loss from the model is validated by experimental studies. The results of the model application to compute the AC power loss dependence on the distance between SC layers are confirmed by our recent experiments. The approach is extended to compute the dependence of the AC power loss on different temperatures and strengths of the magnetic field. Asymptotic for the AC power loss at large N is derived. For N→∞, the AC power loss reaches a plateau and its value is found.