Study on Characteristics of ±800kV DC Composite Insulators

This paper presents the basic structure parameters of 800 kV DC composite insulator specimen and the pollution test scheme under whole voltage and whole structure dimension. The condition of 800 kV DC composite insulator pollution test under whole 800 kV voltage and whole structure dimension completed in STRI, which is completed first time in the world, is introduced. The study results indicate that the linear relation between the flashover voltage and the length of 800 kV DC composite insulator is high-blooded. The consistency of test data between STRI and CEPRI is good. The flashover characteristics of I string and V string under whole voltage and whole structure dimension is confirmed. The formula of DC pollution flashover grads calculated by SDD of DC composite insulator is obtained.