Primary and backup protection for fault current limited MVDC shipboard power systems

Robust management of short-circuit faults in MVDC systems must rely on a combination of communication-dependent and communication-independent methods. In one approach, an MVDC system is designed to operate without breakers [1], so both methods rely on coordinated control of power converters and non-fault-breaking mechanical disconnect switches to effect the fault clearance process-fault detection and localization, complete de-energizing of the system, isolation of faulted branch and re-energizing of the system. The Centralized Fault Management (CFM) method depends on communication between distributed sensors and a central decision-making authority to achieve fastest primary protection. It is backed up by a local response function, Localized Fault Management (LFM), that takes over in case of failure in the primary method. To validate not only that the CFM and LFM can work independently but also that they can perfectly integrate and are compatible with each other, an overall shipboard power system was first modeled and simulated within a MATLAB-Simulink environment and partially implemented in a Hardware in Loop (HIL) environment.