Abstract
The integration of offshore wind farms has revitalized the interest in multi-terminal high voltage direct current (M-HVdc) transmission grids. HVdc breakers' importance has increased as M-HVdc grids are now a commercial truth. Several HVdc circuit breaker technologies have been developed, published, and appeared as prototypes for HVdc networks. This paper summarizes the HVdc breaker technologies from the last two decades, distributed mainly in literature. A comparison of various state-of-the-art HVdc breakers is presented. Further, areas are identified where further research and development are required. The goal is to provide primary challenges and prospects in the HVdc breaker field.