Performance of extruded ethylene-propylene rubber insulated cryogenic power cable

Electrical and mechanical properties of ethylene propylene rubber (EPR) pieces were studied in comparison with polyethylene (PE) in the cryogenic temperature region to examine the possibility of applying EPR as a solid electrical insulating material for superconducting cables. Based on the results, an extruded EPR-insulated cable was fabricated. Cooling tests of the 15-m cable down to liquid helium temperature were performed six times and no crack was observed in EPR insulation. The cable was free from partial discharge at this temperature. A long term cooling test at liquid nitrogen temperature was also carried out without any problems.<
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