AC loss measurement and simulation of a coated conductor pancake coil with ferromagnetic parts

Magnetic diverters are commonly used in order to reduce the AC loss in superconducting coils. However, they have not been proved to work on YBa2Cu3O7−x-coated conductor coils. Moreover, modeling tools are required for predicting the resulting AC loss and understanding the loss mechanisms. In this paper, a coated conductor pancake coil with ferromagnetic diverter is measured and simulated. The magnetic diverter reduces the AC loss but the critical current practically does not change. Our simulations show that a diverter wider than that in the measurements can reduce the loss below that of a single strip. Therefore, the optimum diverter size should be obtained by simulations.