Adaptive Overcurrent Protection Scheme for Shipboard Power Systems

Abstract

Future naval ships will be all-electric, with an integrated power system that combines the propulsion power system with the rest of the ship?s electrical distribution system. Reconfiguration of the power system will increase fight-through and survivability of ships, but will also require the systems that support the power system, such as the protection system, to be automatically updated to match current power system needs. This thesis presents an adaptive relaying scheme for shipboard power systems, to automatically modify relay settings after power system topology changes. Multiple Groups of relay settings are predetermined and stored in the digital relays that are protecting the power system. The active Group of settings is automatically determined based on the open/close status of breakers and switches. The developed protection scheme is tested on two test cases by digital simulation using CAPE software and on one case by closed-loop simulation with RTDS and SEL-351S relays.