Condition based maintenance on MV circuit breakers

Condition based maintenance of MV circuit breakers represents an effective way to improve the continuity of supply, reducing operation costs as well. For this reason Enel Distribuzione, the major Italian utility in electric power distribution, has recently started a series of experimental analyses on this type of equipments, with the aim at finding out a way to implement a self-consistent diagnostic system. The application of a preliminary Failure Mode Effect Analysis allowed to determine the critical elements of circuit breaker, related to the most frequent failure modes experienced in service. Experimental tests, carried out on pre-defined quantitative failure configurations, provided interesting results for the selection of most significant diagnostic parameters and their respective sensor system. Cost Benefit Analysis lead the technical considerations and choices throughout this work.