  Power system robustness against high impact low probability events is
becoming a major concern. To depict distinct phases of a system response during
these disturbances, an irregular polygon model is derived from the conventional
trapezoid model and the model is analytically investigated for transmission
system performance, based on which resiliency metrics are developed for the
same. Furthermore, the system resiliency to windstorm is evaluated on the IEEE
reliability test system (RTS) by performing steady state and dynamic security
assessment incorporating protection modelling and corrective action schemes
using the software Power System Simulator for Engineering (PSS/E). Based on the
results of steady state and dynamic analysis, modified resiliency metrics are
quantified. Finally, this paper quantifies the interdependency of operational
and infrastructure resiliency as they cannot be considered as discrete
characteristics of the system.
