Seismic loss assessment: the case study of the power distribution network in Arak city, Iran

Vital infrastructures have, nowadays, a high level of importance in urban areas. Any disruption in one of the infrastructures can cause severe impacts on inhabitants and consequently can affect the other infrastructure systems. In this regard, the electricity grid is considered to be one of the most critical infrastructures, and it has been performed vulnerable to natural hazards, specifically in past earthquakes. Iran is located in a high seismic activity region. Therefore, in this study, the seismic vulnerability of the power distribution network in Arak city has been comprehensively investigated. The power grid has three sections consisting: the electricity generation, transmission, and distribution. In this study, a seismic risk analysis was carried out on its distribution section. The obtained results show that the seismic hazard in the north-eastern part of Arak city is at the lowest level, and in the south-west region, it is at the highest level. Then, the potential damage to the network and the possible financial losses have been calculated. It was revealed that the 315 KVA transformer substations, 615 KVA transformer substations, and finally transmission lines, are at the highest seismic risk of financial damage. According to the obtained results, the probable financial losses for a return period of 475 years event for the 315 KVA transformer substations, the 615 KVA transformer substations, the transmission lines with 120 mm and 70 mm aluminum wires are, respectively, 22300000, 5717000, 270000, and 700000 U.S. dollars.