Insulation coordination optimization study for ±660KV EHVDC project with increased transmission capacity

摘要

The EHVDC transmission systems have the advantages of long-distance and high-capacity power transmission capability, in order to better play the advantages of the EHVDC transmission systems mentioned above, State Grid Corporation of China (SGCC) had proposed to increase the transmission capacity of ±660kV UHVDC transmission system, and increase the bipolar rated capacity from 4000MW to 4600MW, and the research relied on Ningdong-Shandong ±660kV EHVDC project. Based on the researched results of overvoltages in ±660kV EHVDC transmission system with the capacity of 4600MW, the insulation coordination for this transmission system is researched, and the obtained results are compared with that for ±660 kV EHVDC transmission system with the capacity of 4000MW. The content of insulation coordination includes determining insulation level of substation electrical equipment and air gap distance, and determining the line insulator configuration and air gap distance, which can provide references for the planed ±660 kV UHVDC transmission project from Xinjiang China to Pakistan, which will go into operation before 2020.