Seismic reliability of electric power transmission systems

Electric power transmission systems are networks of nodes (stations) connected by lines (power transmission lines), dedicated to the production, transformation and distribution of electric power to users. The network contains many seismically fragile elements, the stations being composed of slender steel-ceramic members, and is a complex system because it is capacitive and capable of insulating short-circuits. In the present work the functional logic of a generic electric network is analyzed and a model suitable for reliability assessment is estabilished. The model is then applied to evaluate the seismic reliability of a realistic network comprising the central part of Italy, using simulation methods. Various measures can be adopted to assess the performance of a network: the one selected in this study is a global index related to the quantity and the quality of the power delivered.