Evaluating the impact of component unavailability on power distribution feeder reliability

Abstract

The power distribution system reliability is the key driver for service quality as well as customer satisfaction. In this study, the impact of component unavailability on overhead as well as underground distribution feeder reliability is analyzed in terms of reliability metrics like SAIFI, ASAI, ENS, CAIDI, and SAIDI. Due to environmental conditions, overhead power distribution lines face many challenges, while underground power distribution cables are superior to this due to their resiliency and performance. The reliability of distribution feeders varies based on the analysis of different protective devices such as fuses, disconnecting switches, and alternative supplies as well as the restoration process of transformer failure. Using the analytical approach, this study evaluates the reliability of both feeder types such as overhead and underground in different unavailability cases. It is observed that the reliability level of feeders is greatly impacted by the absence of these devices. The results also show that the feeder reliability is improved when overhead power lines are replaced by underground power cables, resulting in a reduced number of outages and durations.