Development of Grounding and Fault Localization in Power Electronic-Interfaced MVDC Shipboard Power and Energy Systems

Medium Voltage Direct Current (MVDC) shipboard power systems are being developed for next generation naval warships. To realize this goal, standardization of suitable grounding and ground fault localization are two significant efforts under development. These efforts are part of a multiphase research effort working towards interface standardization of MVDC shipboard power systems. This paper presents a short-circuit transient study of two different dc grounding methods and a fault locality study based on US Patent 8067942 B2. The short-circuit transient results show that voltage recovery post-fault is governed by the redistribution of parasitic capacitive charge via the parasitic conductance in the system verifying fundamental assumptions. For the fault locality study, distinct differences in the voltage oscillatory behavior are seen depending on the location of a line-to-ground fault, justifying the use of the methodology in MVDC systems.