A Reliability Allocation Method Based on Fault Tree and Optimization Method

ABSTRACT In the early stages of system design, due to the lack of detailed information, unconstrained methods are often adopted. Among these, the weighted factor allocation method is a common approach. However, this method is mainly suitable for series systems. Although some extended methods allow its application to more complex series‐parallel systems, these methods are often influenced by subjective scoring. To address this issue, we propose a system reliability allocation method based on fault tree models and optimization methods. This approach constructs a fault tree model considering the impact of common cause failures and establishes an objective function between system reliability and the reliability to be allocated. Through optimization algorithms, the minimum value of the objective function is found, and the optimal solution of this objective function is the allocation result of the reliability target. This method can be implemented in the early stages of system development and does not rely on expert experience. We demonstrate the effectiveness of this allocation method through a case study.