Hardware-in-the-Loop Validation of Optimal Adaptive Protection for Utility Networked Microgrid Applications

Abstract

The increased prevalence of distributed energy resources and microgrids has led to highly variable fault current levels and system configurations in distribution networks. To improve power system resilience during severe weather events, microgrids can be networked outside of their original boundaries to restore service to additional customers. Traditional protective relaying schemes may not be equipped to handle these contingencies. Optimal Adaptive Protection (OAP) algorithms can provide more robust system protection during such events by monitoring the network for system state changes and modifying protective relay settings in near real-time. In this paper an OAP algorithm is applied to systems from three different utilities, modeled in OPAL-RT, and connected to hardware-in-the-loop (HIL) relays. Restoration scenarios are considered starting from islanded microgrids and returning to normal operating conditions. By incorporating OAP after any network switching event, protection security is improved throughout the restoration process.