Electrical insulation for high temperature superconducting fault current limiters

This paper provides an overview of the electrical insulation of high temperature superconducting fault current limiter (HTS FCL) by singling out from the literature a few aspects that are critical for such insulation. The performances of some important insulating materials such as organic polymers with fillers, non-filled ethylene propylene rubber (EPR), polyimide and epoxy nano-composites are reported. The main elements of the electrical design and withstand tests of mini-model coils are described. Moreover, as practical applications of such concepts, the paper illustrates the electrical insulation design of a 13.2 kV/630 A bifilar winding type HTSFCL with YBCO coated conductor (CC) wire and of a cryogenic bushing for superconducting power applications.