Resistance Dependence of the Magnetization Loss for the Partially Coupled REBCO Stacks Modeled by MEMEP Method

Abstract

Generally, HTS tapes are stacked and connected to improve the current carrying capacity in real large HTS machinery. This kind of stack is defined as partially coupled stack because there are resistances at both soldering ends of the stack, which will induce coupling current and cause resistance loss when a parallel sinusoidal magnetic field is applied. The resistance value affects the resistance loss a lot. The magnetization loss character of the partially coupled stack is studied by the minimum electromagnetic entropy production in 2D (MEMEP 2D) method systematically. The result shows, when the resistance is extremely small, the resistance loss is too small to affect the magnetization loss. When the resistance is extremely large, there is no coupling current or resistance loss at all. When the resistance is not too small or too large, an obvious resistance loss is observed and there is a pick value which is relate to the structure parameters and the amplitude of the applied magnetic field. The resistance dependence in magnetization loss of the partially coupled stack under a series of ac magnetic field amplitude and frequency are discussed. The results reveal the features of resistance loss which is very helpful to devices with multi-tape conductors for real large HTS machinery.