DEVEIOPMENT PROSPECTS OF HIGH ECONOMY XLPE INSULATION HVDC SUBMARINE CABLE

The material consumables of HVDC submarine cable required per unit transmission capacity was taken as a typical economic index, based on that, the economy of HVDC submarine cable was improved both with voltage and current capacity increasing for a single HVDC submarine cable circuit. Compared the material consumables with the increase of voltage and the current capacity of HVDC submarine cable based on different routes, it was cleared that the improvement of voltage and current capacity respectively by increasing the Insulation tolerance level and the maximum operating temperature of conductor is more effective in improving the economy of HVDC submarine cable. In addition, ±525kV DC submarine cable was selected as a typical specification, whose insulation field strength distribution was analyzed through finite element simulation after the applied voltage was increased to 972kV and the conductor operating temperature was increased from 70°C to 90°C. The results showed that the increase of applied voltage and conductor operating temperature would both caused a further increase of the field strength close to the insulation shield after the insulation field strength reversal, and there is an additional synergism between voltage and temperature.