MMC‐HVDC Transmission Technology and MTDC Networks

Line‐commutated converter high‐voltage direct current (LCC‐HVDC) transmission technology is widely recognized as being advantageous for bulk power transmission over long distances, asynchronous interconnections of ac power systems, and interconnectors with long submarine cable. New modular multilevel converter (MMC) designs have broadened the potential range of HVDC transmission to include application of HVDC schemes in weak ac networks. MMC‐HVDC technology is foreseen as the most suitable technology for development of multi‐terminal direct current (MTDC) networks. This chapter presents different HVDC scheme configurations and MTDC configurations. It describes various dc grid control and protection strategies, including dc breaker technologies. The LCC‐HVDC transmission is the preferred transmission technology for bulk power transmission with overhead power lines over long distances. The LCC‐HVDC transmission technology cannot be utilized in weak ac networks, such as islanded offshore WPPs. Finally, the chapter presents dc breaker technologies with passive components and solid‐state hybrid breaker technologies.