Two application examples of probabilistic risk assessment in power system operations

This paper demonstrates two application examples of probabilistic risk assessment (PRA) in power system operations. In the first example, a risk based method is proposed to take the uncertainty of contingency occurrence and impacts into account to provide an essential set of contingency cases for a transient stability special protection system (SPS) implementation. In the second example, an approach for determining the power transfer limit of a longitudinal electric power system is presented. In these examples, the PRA method retains the numerical tools and procedure of the traditional deterministic approach, but also includes the computing of operations risks which accounts for contingency occurrence probability and impacts in terms of load shedding and generation rejections for avoiding system transient instability