Multiterminal HVDC Networks—What is the Preferred Topology?

This paper investigates the influence of dc network topology with respect to two important aspects: the steady-state losses and the transient fault currents. For this, optimal power flow in a combined ac-dc multiterminal HVDC cable system based on voltage-source converters and the development of prospective fault currents during a pole-to-ground fault is simulated. The results prove that an evaluation of grid topologies must include both of the aforementioned aspects and that no network topology can optimize both at the same time.