An intelligent maintenance model to assess the condition-based maintenance of circuit breakers

Abstract

Summary The circuit breaker (CB) is one of the most important equipment in power systems. CB serves as both control and protection equipment, and its operating condition is critical to the stability and reliability of power systems. CB must operate reliably to protect power systems as well as to perform tasks such as load disconnection, normal interruption and fault current interruption. As the number of equipment increases and the demand for reliability grows, many utilities switch to condition-based maintenance (CBM) for better system operation efficiency and lower operating cost. This paper proposes a CB CBM model which integrates fuzzy set theory (FST), analytical hierarchy process (AHP) and evidential reasoning (ER). Two assessment factors, i.e. (i) operating mechanism and (ii) CB lifetime, are selected as the condition parameters. A hierarchical assessment index system is constructed based on intelligent electronic device (IED) monitoring data. FST is applied to analyze the CB condition assessment indices provided by the IEDs. Data collected from questionnaires after interviews with experts are utilized by AHP to calculate factors and index weights. The ER algorithm is applied to calculate each factor by combining the indices and by combining the factors to generate the overall assessment of the CB condition. Maintenance activity is scheduled according to the CB condition assessment. Field examples are given to illustrate the application of the model in assessing CB operation conditions. Copyright © 2014 John Wiley & Sons, Ltd.