Mechanical force optimization on superconductor element of shield-type superconducting FCLs

Superconducting fault current limiter (SFCL) is classified in the category of most efficient fault current limiters. Inductive shield-type SFCLs use bulk superconductor rings in their structure. At the fault occurrence, the induced current in the superconductor ring causes high mechanical forces on the ring. In the preliminary fabricated prototypes of this work, this mechanical force caused several damages to the superconductor element. Thus in this paper an analytical method is introduced to yield the main design parameters of the shield-type SFCL to ensure the sufficient mechanical withstand capability of the superconductor ring employed in this design. A prototype SFCL of this type is fabricated in this work (using the superconductor ring parameters, determined through this analytical method) to limit the fault current to about 2 A. The fabricated device is tested and no damage occurred on the superconducting ring.