Condition Based Maintenance Optimization for Multi-component Systems

Abstract

Most existing condition based maintenance (CBM) work reported in the literature only focuses on determining the optimal CBM policy for single units. Replacement and other maintenance decisions are made independently for each component, based on the component’s age, condition monitoring data and the CBM policy. In this paper, a CBM optimization method is proposed for multi-component systems, where economic dependency exists among the components subject to condition monitoring. In a multi-component system, due to the existence of economic dependency, it might be more cost-effective to replace multiple component at the same time rather than making maintenance decisions on components separately. Deterioration of a multi-component system is represented by a conditional failure probability value, which is calculated based on the predicted failure time distributions of components. The proposed CBM policy is defined by a two- level failure probability threshold. A method is developed to obtain the optimal threshold values in order to minimize the long-term maintenance cost. An example is used to demonstrate the proposed multi-component CBM method.