Thermo-insulation characteristics of PPLP used for superconducting cable

Abstract

Abstract High temperature superconducting (HTS) cable has attracted more attention for its high current density, low loss, and small size. The insulation structure design of HTS cable is very important for the safe operation. Many of the cold dielectric HTS cables use PPLP as the insulation material. However, the HTS conductor needs to endure temperature higher than 150°C during the manufacturing process, and the effect of high temperature on the insulation characteristic of PPLP is unclear. The DSC curve of PPLP was analyzed, and the melting temperature of PPLP was 164.3 °C. The oven was used to heat PPLP for 10 min, 20 min, 30 min, 1 h, 2 h. The heated PPLP was subjected to a power-frequency AC breakdown experiment. It was found that the AC breakdown voltage of PPLP is less than that of unheated PPLP, and its insulation performance degrades.