Estimation of cascade failure probability in electrical transmission networks by Subset Simulation

In this work, standard Monte Carlo Simulation (MCS) and Subset Simulation (SS) are ap-plied for assessing the probability of cascading failures in network systems. The latter method has been origi-nally developed to solve structural reliability problems [Au and Beck, 2001], based on the idea that a small failure probability can be expressed as a product of larger conditional probabilities of some intermediate events. A model of cascading failure dynamics previously presented in the literature is taken as reference to predict the size of cascading failures in network systems, under realistic loading. In the application, SS is shown to be more efficient than MCS. The sensitivity of the system response to uncertain parameters is also studied.