Distributed voltage control and fault management of star-connected multi-terminal VSC MMC systems

The generation capacity of wind farms in the north and north-east area of Germany is growing continuously. At the same time the nuclear phase-out leads to the shutdown of power plants mainly in the southern part of Germany and causes a regional deficit of generation capacity. As a consequence, the German transmission grid needs significant reinforcements for the integration of renewable energy into the power system as well as to ensure the security of supply in the south. With regard to losses, power per transmission line and system performance requirements, HVDC based on the VSC MMC technology is the most promising technology for this task. This paper initially carries out a comparison between point-to-point, starconnected multi-terminal systems and meshed DC-grids. Subsequently, a…