Research on Insulation Coordination Design for ±600kV Bipolar HVDC Transmission Line with Dedicated Metallic Return in Chile

The paper developed a new insulation coordination design method to create a tower head electrical design, which meets the requirements of environmental conditions for the first ±600kV HVDC Kimal Lo Aguirre (KILO) project in Chile. Based on the results of the overvoltage study, and considering the local Chilean climate and pollution research results, combined with the mature design and operational experience of ±800kV transmission lines in China, specific recommendations were made for the selection of insulators for the pole conductors and Dedicated Metallic Return (DMR). According to the relevant standards such as the current IEC standards, Cigre standards, and Chilean regulations, the electrical clearances for the pole conductors and DMR of the ±600kV HVDC project were calculated. By integrating the recommended insulator types and electrical clearance values, typical tower head electrical design suitable for the ±600kV HVDC transmission project with DMR was developed.