Thermo-electric field analysis of AC XLPE cable in monopole, bipole, and tripole DC operation modes

摘要

This paper presents a numerical analysis of thermo-electric fields of 10 and 35 kV AC XLPE cables in monopole, and tripole DC operating modes based on conduction current measurements. DC conductivities and electric field thresholds of the space charge accumulation for XLPE materials were estimated at different temperatures and electric fields. The result showed that the electric field threshold of the space charge accumulation for the materials reduced with an increase of the temperature. DC currents of the cables were increased with the increase of the operating temperatures in the three DC operation modes. The maximum DC operation voltage of the cables increased with the decline of the operation temperature in the three DC operation modes. The maximum transient electric fields were below the threshold of the space charge accumulation for the cables in the tripole DC operation. The maximum transmission power of the 10 kV XLPE cable in the DC operation modes was at 60 degrees C, whereas the maximum transmission power of the 35 kV XLPE cable was at 50 degrees C. It was elucidated that the 10 kV AC XLPE cable could have more advantages than the 35 kV AC XLPE cable in the three DC operation modes.