Interoperability of voltage source converters in dc grids

This study examines the possibility of operating different voltage source converter topologies in high-voltage direct current grids. The investigation is motivated by growing concern from the utility companies and transmission system operators regarding the compatibility of these converters, especially the behaviour of resultant multi-vendor dc grids during ac and dc network faults. In an attempt to establish the credibility of the expressed concerns, the transient response of illustrative multi-vendor six-terminal dc grids that consists of four two-level converters, a two-switch modular converter and a H-bridge modular converter are examined during ac and dc network faults. The main results obtained and observations drawn are highlighted and discussed.