We aim to demonstrate an efficient method to calculate the AC losses in multi-pancake coils. This method extends Yuan front-track model into several pancake application and investigates the detail parameters in comparison with established H-formula implemented in COMSOL and minimization of energy method. We use the front-track idea to analyze stacked pancakes assuming the current fronts are straight lines and using the critical state model. The current distribution is solved by two means: minimization of the perpendicular magnetic field in the subcritical region, as Clem and Yuan proposed; minimization of total magnetic energy. We also investigate the impacts of applied current and different gaps between multi pancakes on loss calculation. Our model provides a fast calculation method of AC loss in stacked (Re)BCO pancakes and is useful to HTS applications in high field magnets, energy storage devices and electric machines.
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