On the Influence of Switch Inductance in Zonal DC System Stability

Most advanced navy ships are nowadays conceived to attain a totally controlled power grid with high reconfigurability and resiliency. The latter are the key-features of DC zonal microgrids, where the widespread adoption of power electronics ensures the load supply even during critical events, like a zone blackout. In the zonal configuration, a remote-maneuverable DC switch is to be installed on the mutual interconnection among buses to independently provide power to the feeders. As the DC switch is characterized by an intrinsic inductive nature, its presence could be negative in regarding to the DC system stability. Basing on this possible criticality, the paper wants to explore the influence of DC switch inductance on the stability of a zonal DC power system. A convenient modeling will provide a simplified equivalent circuit on which the stability conditions are made evident, thus clarifying the switch effect. Final tests on Hardware In the Loop platform will prove the validity of analytical stability boundaries.