Maintenance Modeling for a Multi‐Component System Considering Dynamic Importance of Components and Imperfect Repair

ABSTRACT A system consisting of a critical and an auxiliary component is studied, and imperfect maintenance models considering degradation interaction and maintenance effect are developed. The auxiliary component assists the critical one in completing the system function, and its failure does not directly lead to the system failure. When the critical component deteriorates to the preventive maintenance (PM) threshold, it is restored by PM. When the auxiliary component deteriorates to a poor condition, significantly affecting the system reliability, the dynamic importance of the auxiliary component is considered, and the maintenance decision is provided according to the state of the auxiliary component. By minimizing the system's long‐term average cost, the optimal PM threshold for the critical component and maintenance threshold for the auxiliary component are derived. Finally, the effectiveness of the proposed model is further demonstrated with examples, comparison with previous model and comprehensive sensitivity analysis.