Design considerations in MgB2-based superconducting coils for use in saturated-core fault current limiters

Saturated-core fault current limiters (FCLs) are devices that have many applications and potential for use within power networks. At a commercial scale, these devices require high H-field magnets to saturate the steel core, which can typically only be achieved through the use of superconducting coils. Here, we present several challenges that arise in the application of superconducting coils in FCLs and discuss how to address these issues through a case study MgB2-based coil. It is found that significant ac magnetic fields, Lorentz forces, and Joule heating in components occur during normal and fault operations; however, these issues can be mitigated when properly addressed.