Physical performance of power grids against earthquakes: from framework to implementation

Resilience analysis of power grids requires their performance assessment during threatening hazards. However, the diverse connections among various constituent components make studying power grids' network behavior complicated. This study aims to present a practical framework with appropriate computational speed and acceptable accuracy in estimating the seismic physical performance of power grids, such that both electrical and earthquake experts can easily use it. The framework has provided a performance indicator by implementing the system's component-based analysis in the network-based graph model. This indicator has been calculated based on distinguishing the components under power service, failed components by direct physical damage, and failed components by indirect physical damage from each other (network-based). The proposed indicator has also considered the physical capacity lost/remaining in both under-service and out-of-service components (component-based). Consequently, It can distinguish among the network components beyond the binary classification of performance and failure. In other words, while maintaining the positive features of binary connectivity analysis, higher accuracy has been obtained for a preliminary estimation of the system's physical performance. The variety of seismic scenarios for the selected case study provided the possibility of examining and comparing different network performance states on three levels: physical blackout, physical outage, and no physical interruption. The practical functionality of the indicator, verified by a prototype graph, and the merits such as higher accuracy than commonly used connectivity analysis, simplicity, and rapidity make it a user-friendly method in interdisciplinary studies of electricity and earthquake engineering.