Topological and technical characteristics analysis of large-scale renewable energy HVDC transmission

The paper aims to analyse the development, technological pathways, and applications of large-scale renewable energy Voltage Source Converter-based High Voltage Direct Current (VSC-HVDC) transmission. The paper begins by comparing the key differences between LCC-HVDC (Line Commutated Converter High Voltage Direct Current) and VSC-HVDC, assessing the advantages and disadvantages of VSC compared to LCC. It then focuses on the Modular Multilevel Converter (MMC), which represents the third generation of VSC, and discusses its topology and technical characteristics. Additionally, the paper examines typical application scenarios for VSC-HVDC and emphasises the advantages of VSC-HVDC in these contexts. Finally, an in-depth analysis of China's leading VSC-HVDC projects highlights their innovative topology and unique technical characteristics, showcasing their pivotal role in various application scenarios, including long-distance transmission, renewable energy grid connection, and grid interconnection. The results show that VSC-HVDC, with its efficient, flexible transmission capability and fault ride-through advantages, has become a key driver in promoting renewable energy development and optimising power grids.