Modeling and simulation of shipboard power system protection schemes using coordination of overcurrent relay

Combining the modeling and simulation of power systems and control systems is a challenge. Several packages allow the optimization of either the power system functionality or the control system functionality. Research efforts are underway at Mississippi State University to model the protection functionality of microprocessor controlled relays to allow the integration of the protection system and power system models for advanced optimization and simulation analysis related to shipboard power systems (SPS). This paper presents a detailed overview of the overcurrent relay model and procedures used to conduct closed loop coordination testing of relays using a real time digital simulator (RTDS). The coordination of a relay is a useful concept, which is used widely in the protection of a power system. This paper mainly focuses on the coordination of overcurrent relays in order to protect the SPS after severe disturbances.