A flow importance measure with application to an Italian transmission power system

Potential catastrophic events have been historically assessed through the techniques of power system security analysis. A correct assessment must consider not only events associated with "credible outages" but also the possibility of attacks and/or "rare" events. This paper combines concepts of reliability engineering and operations research to develop a new importance measure, D(α), that identifies the most vulnerable group of α links in a network. Since the computation of the new importance measure, D(α), becomes computationally prohibitive for large systems, an approximation technique is provided based on the optimization of a multi-objective deterministic network interdiction problem. The efficiency of the algorithm is then illustrated by analyzing the Italian high-voltage electrical transmission network. In summary, D(α) can be useful for an initial screening of the critical elements of the network.