Probabilistic cascading event risk assessment

This paper describes an algorithm for the identification of rare events with high severities, potentially leading to blackouts in power systems, and the quantification of the risk a given system state holds. Based on the method of probabilistic load flow, probability density functions of the branch loadings under consideration of the forecast uncertainty are determined. From that branch tripping probabilities are derived. Using these tripping probabilities, numerous cascades are simulated. As the main output of this method the overall risk is calculated. This method is applied to the IEEE 118-bus test system extended by uncertainty data and outage statistics.