External system line outage identification using phasor measurement units

This paper investigates the problem of line outage detection in an area external to the operating area boundaries. The so-called “internal system” is assumed to be fully observable and the base case topology of the external system is assumed to be known. A limited number of phasor measurements are also assumed to be available from the external system. The paper takes advantage of the equivalent representation of a line outage by a pair of injections at the line´s terminal buses and formulates the outage detection problem as an integer programming problem. Results are verified by simulating various external line outage scenarios using the IEEE 118-bus test system.