Protection system monitoring for the prevention of cascading events in smart transmission grids

With the diffusion of standardized communication protocols in smart transmission systems, it is expected that digital distance relays will become active elements in monitoring and control architecture. Real-time tuning of distance relays settings will allow to overcome the classical conflict between dependability and security, or to avoid improper operation of such devices in vulnerable conditions and during major blackout events. In this paper, along with the presentation of a monitoring and control architecture that integrates such devices into SCADA/EMS, a system security monitoring function, based on simulated system trajectories and their closeness to distance relay zones, is proposed for system operation and contingency analysis.