Investigation of the insulation system of 500 kV XLPE cables

The statistical approach to the design of XLPE cables is presented in detail. The voltage withstand level of 500 kV XLPE cable insulation based on the principle of insulation coordination is discussed. The philosophy to determine the insulation thickness of 500 kV XLPE cables in terms of statistical design procedures and the quality control requirements in reference to those of 500 kV XLPE cables being operated in Japan is justified. Finally, the insulation thickness of 500 kV XLPE cables of different crosssectional areas used in China are proposed.