Uncertainties in real-time external modeling for state estimation: A heuristic practice

State estimation plays the key role in real-time bulk power system reliability operation and economical market operation. Active transactions across the regional transmission systems are integrated nature of today´s electricity markets. To ensure stable and adequate SE solution, EMS engineers are paying more attentions on external network models, which usually deal with real-time operation uncertainties in the neighbor systems. This panel will discuss a heuristic approach on external model analysis focusing on important tie-line post contingency flow and across-region transfer flow adequacy with sensitivity and observability indices for external model boundary cut. Practical cases will be discussed.