Feasibility evaluation of DC extruded cable with conductor operating temperature of 90°C

In recent years, flexible DC transmission technology has developed rapidly. In China, the rated voltage of extruded HVDC project has raised to 400kV since Dec. 9
^th
, 2021. In order to improve transmission power more effectively and obtain higher economic benefits, the increase of voltage level and maximum conductor operating temperature will be future development trend. In this paper, the construction of ±535kV DC cable with maximum conductor operating temperature of 90 °c is introduced. The current carrying capacity of DC extruded cable is approximately calculated. The qualification process and the results of HVDC system are present. The volume resistivity parameters are obtained by testing the cable insulation slice samples under different field strengths and temperatures.