Impact of topology and fault current on dimensioning and performance of HVDC circuit breakers

Multiterminal HVDC networks are a key technology for future power transmission. For safe and reliable operation, it is necessary to equip these with HVDC circuit breakers. In the presented paper, four HVDC breakers, representing different breaker classes, are dimensioned and simulated in synthetic and exemplary grid fault cases. The results are used to illustrate topology dependent limitations and individual options to upgrade each circuit breaker. Additionally, differences between commonly used linear fault currents and faults in MTDC grids as well as their implications are highlighted.