Preventive maintenance optimization to improve quality in electrical power systems

An optimization method to schedule preventive maintenance of electrical power system is described. The method is based on the frequency of failures with related probability distributions and on a conventional age estimation for each component according to a "substitution at a certain age" procedure. The economic convenience to repair before or after failure is evaluated, an optimization of stored spare parts is analyzed, and Logistic Waiting Time computations are supplied to establish outage costs due to electric service interruptions. The proposed method requires a preventive FMECA (Failure Modes, Effects and Criticality Analysis) that in this paper is implicitly assumed as already performed.