Modeling the Resilience of Power Distribution Systems Subjected to Extreme Winds Considering Tree Failures: An Integrated Framework

Abstract

Overhead electrical power distribution systems (PDS) are very susceptible to extreme wind hazards. Power outages can cause catastrophic consequences, including economic losses, loss of critical services, and disruption to daily life. Therefore, it is very important to model the resilience of PDS against extreme winds to support disaster planning. While several frameworks currently exist to assess the resilience of PDS subjected to extreme winds, these frameworks do not systematically consider the tree-failure risk. In other words, there is no integrated framework that can simultaneously consider tree failures, PDS component failures induced by falling trees, resilience assessment, and evaluation of resilience enhancement with vegetation management. Therefore, this study proposed an integrated simulation framework to model the resilience of PDS against extreme winds, which includes tree fragility modeling, PDS fragility modeling, PDS component failure estimation, system performance evaluation, system restoration modeling, and resilience enhancement evaluation. The framework is demonstrated with a power distribution network in Oklahoma. The results show that the estimated system resilience will reduce if tree failures are considered. Crown thinning can effectively enhance the system’s resilience, but the effectiveness is affected by both wind speed and direction.