Tracking changes in the external network model

In any interconnected system, each system has real-time access to its own measurements and topology, whereas the real-time external line status information is generally not easily accessible by the internal power system dispatcher. Since the static security analysis is highly dependent on the topology of external system, it is critical for the internal system operator to be aware of any external topology changes. Currently, information about the breaker status in the external system is not commonly telemetered to the internal system. Therefore, external line outage detection remains a potential problem to a large number of utility companies. This paper proposes a new method to identify an external network line outage based on the internal system measurements.