Research ArticleReal-time reliability evaluation methodology based on dynamic Bayesian networks: A case study of a subsea pipe ram BOP system

- A two-phase real-time reliability evaluation methodology is proposed.
- A root cause diagnosis phase and a reliability evaluation phase form the frameworks.
- BNs and DBNs are used for root cause diagnosis and real-time reliability evaluation.
- The methodology can give the real-time reliability value when the faults occur.
- The methodology can give the importance degree sequence of components.

A novel real-time reliability evaluation methodology is proposed by combining root cause diagnosis phase based on Bayesian networks (BNs) and reliability evaluation phase based on dynamic BNs (DBNs). The root cause diagnosis phase exactly locates the root cause of a complex mechatronic system failure in real time to increase diagnostic coverage and is performed through backward analysis of BNs. The reliability evaluation phase calculates the real-time reliability of the entire system by forward inference of DBNs. The application of the proposed methodology is demonstrated using a case of a subsea pipe ram blowout preventer system. The value and the variation trend of real-time system reliability when the faults of components occur are studied; the importance degree sequence of components at different times is also determined using mutual information and belief variance.