Lapping dielectric design of 110 kV HTS cable body

High temperature superconducting (HTS) cable is developing towards the direction of bigger capacity and higher voltage grade, 110 kV cold dielectric HTS cable has being developed in China. Polypropylene laminated paper (PPLP) is a widespread used film dielectric material for cold dielectric HTS cable, it is usually lapped on the conductor. So the dielectric characteristics may be effected by the lapping tension. In this paper, the lightning impulse dielectric breakdown strength of PPLP under tensile status is tested by a special electrode system. The experimental results are processed by method of Weibull plot. The impulse dielectric breakdown strengths of 0.1 % breakdown probability under different tensile stresses are achieved. Combining experimental results and design methods related, the lapping thickness and layers of PPLP used for 110 kV cold dielectric HTS cable are designed.