Analysis and enhancement of resilience of the electricity distribution network of Ardabil province using interruption data

In this paper, the resilience of the Ardabil province power distribution network was investigated at the level of medium voltage feeders by studying the interruptions of the feeders caused by weather conditions. To do this, the weighted sum of the “number of failures due to weather condition (NFW)”, “failure time duration due to weather condition (FTW)”, and “energy not supplied due to weather condition (ENSW)” were used as an index to assess the resilience of the network. Considering the power interruptions of the last five years, for the interruptions caused by the weather conditions, the numerical value of the defined index for the electricity distribution network of Ardabil province resulted in about 20%, which indicates that the resilience of this network is about 20% less than its ideal value (it is about 80%). To reduce the defined index (increase the resilience), one of the preventive methods is to harden the equipment used in the distribution network for which the feeders that have the highest impact on the defined index were extracted as high-risk feeders to be hardened. Also, to increase the resilience of the Ardabil electricity distribution network, some suggestions have been made to harden high-risk feeders. For this purpose, a number of high-risk feeders were visited to determine possible design discrepancies (contrary to the standard design announced by Tavanir) or their incorrect implementation. By comparing the current status of the studied feeders with the design standards, solutions were provided to correct and increase the strength of these feeders (preventive action to increase resilience). The implementation of the proposed hardening methods is expected to reduce the number of interruptions (due to weather conditions), which will decrease the obtained index and increase the resilience of the network. Moreover, based on this study, it was found that wind, severe storms, rain, thunderstorms, and snow are the most common causes of outages at the level of medium voltage feeders, respectively.