Sensitivity analysis of the power grid vulnerability to large-scale cascading failures

Abstract

This paper revisits models of cascading failures in the transmission system of the power grid. It has been recently shownthat since power flows are governed by the laws of physics,these models significantly differ from epidemic/percolationbased models. Yet, while some numerical results have been recently obtained based on these models, there is a need to investigate the sensitivity of the results to various parameters and to evaluate the models' accuracy. In this paper, through numerical experiments with real grid data, we study the effects of geographically correlated outages and the resulting cascades. We consider a wide range of parameters, such as the power lines' Factor of Safety and the sensitivity of the lines to power flow spikes. Moreover, we compare our numerical results to the actual events in a recent blackout in the San Diego area (Sept. 2011), thereby demonstrating that the model's predictions are consistent with real events.