State estimation for the interconnected power networks using branch outage sensitivity

This paper addresses the issues of the external system modeling and power system state estimation with the external model. A set of significant branches is identified in the external system based on their outage sensitivities on the tie-lines. Measurements on these branches are transffered to internal system and updated in real-time. The state estimator is run for different loading conditions by using the actual measurements for the internal system and selected significant external system measurements while keeping the rest of the external system measurements at their base case values. Simulation results are presented using the IEEE 118 bus system as an example.