Insulation coordination optimization study for ±800kV UHVDC project with increased transmission capacity

the UHVDC transmission systems have the advantages of long-distance and high-capacity power transmission capability, in order to better play the advantages of the UHVDC transmission systems mentioned above, State Grid Corporation of China (SGCC) proposed to increase the transmission capacity of ±800kV UHVDC transmission system, and increase the bipolar rated capacity from 7200MW to 7600MW. Based on the researched results of overvoltages in ±800kV UHVDC transmission system with the capacity of 7600MW, the insulation coordination for this transmission system is researched, and the obtained results are compared with that for ±800 kV UHVDC transmission system with the capacity of 7200MW. The researched results can be refered by the planed ±800 kV UHVDC transmission systems of China.