Contingency re-definition and its application to power system security analysis

This paper presents the contingency re-definition and its application to power system security analysis. Contingency Analysis (CA) has been an important tool in power system planning and security analysis for many years. Based on real-time network connectivity, the re-definition function takes into account the actual response of protection subsystem on the power system equipment. It identifies the breakers required for isolating the contingency equipment. This provides additional accuracy of post contingency results and provides important data to ensure the remedial action schemes are emulated correctly. Each contingency is simulated in contingency analysis by opening these breakers to evaluate their impact to the system. The ability to recognize and respect the status of manually operated switches is important to ensure the simulation mimics protection schemes. Any non-contingency equipment forced out as a result of these breaker openings, also called sympathetic outages, will be added to the contingency equipment list. All outage equipment and breakers will be listed on the contingency definition display for each contingency case. This function has been integrated in the real-time CA, off-line CA, and into dispatcher training simulator.