Reliability-centred maintenance for circuit breakers in transmission networks

Reliability of power system can be influenced by the maintenance strategy adopted for the system's equipments. This study focuses on power circuit breakers maintenance planning based on the concept of reliability-centered maintenance (RCM) and applies the proposed approach on the 400 kV transmission network in Khorasan province in Iran. The RCM strategy takes into account the technical condition and importance of each circuit breaker from the network's perspective. The technical condition index of a specific circuit breaker is a numerical representation of the physical health of the breaker and can be evaluated by some criteria. To determine this index, the performance of the circuit breakers during interval 2007-2012 is considered. The importance of each circuit breaker is related to the consequence of its failure on the network. As the main drawback of the available researches in this area is the lack of a generic tool to determine the importance of the circuit breakers, this study proposes a three-stage procedure to accurately evaluate the importance of the circuit breakers. The main idea in the proposed approach is to analyse all failure modes of the circuit breakers and simulate the effect of each failure mode on the overall expected energy not served. The obtained results show the efficiency of the proposed approach.