In a medium-voltage power system, fault currents are subjected to uncertainties in lines and distributed generations. Uncertainties in fault currents in a power grid can introduce system protection problems. Superconducting cablewith fault current limiting capability can be used as means to meet the increasing electricity demand while resolving the issues involving system protection. In order to integrate the fault current limiting superconducting cable into a power grid, its impedance selection under fault conditions needs to consider the impact of power system uncertainties on system protection. In this paper, an expected regret-based method is proposed for determining the impedance of the fault current limiting superconducting cable incorporating the uncertainties in fault currents. The results of numerical simulations are presented to show the effectiveness of the proposed expected regret-based impedance selection method.