Effective computing algorithm for maintenance optimization of highly reliable systems

This paper describes a new iterative numerical algorithm for optimal maintenance strategy respecting a given reliability constraint. It stems from the previous authorʹs research work which brings a new direct analytical method that enables exact reliability quantifications of highly reliable systems with maintenance (both preventive and corrective), i.e. the instantaneous unavailability function is computed in full machine accuracy. The method takes into account systems with highly reliable and maintained components, including repairable components undergoing to hidden failures. The new numerical algorithm for maintenance optimization introduced in this article fully respects previously developed exact computing methodology to solve a cost optimization problem where decision variable is maintenance. The algorithm, which is based on merits of a high performance language for technical computing MATLAB, results from linear approximation of total system cost that is supposed to be a linear function of frequency of maintenance and from limiting unavailability approximation in each iteration step. The optimization method is demonstrated on two systems from practice—a real power distribution network and high pressure injection system of a nuclear power plant.