飞控计算机系统分层混合可靠性建模方法

Hierarchical Hybrid Reliability Modeling Method for Flight Control Computer System

对于复杂的非相似、多余度飞控计算机系统,根据其结构特点,综合静态和动态可靠性建模方法的优势,提出了采用可靠性框图(RBD)和广义随机Petri网(GSPN)相结合的分层混合建模方法,并对建模过程中低层各子系统存在共因失效部件情况下的可靠性建模和求解作了分析.分别采用分层混合建模方法和动态可靠性建模GSPN方法对Boeing777电传主飞控计算机系统进行可靠性建模和分析.同动态GSPN方法相比,该方法综合采用了静态和动态可靠性建模方法,具有状态空间模型的灵活性和组合模型求解的高效性,同时层次结构避免了GSPN方法带来的状态空间爆炸问题.由结果比较可得,该方法可行、高效、精确.

According to the characteristics of complex dissimilar,redundant flight control computer system and the combination of the advantage of static and dynamic reliability modeling,the hierarchical hybrid reliability modeling method（HHRM）,which combines reliability block diagram（RBD） and generalized stochastic Petri net（GSPN）,was presented.In the case that components of common cause failures exist in the various low-level subsystems,the system reliability modeling method was analyzed.The HHRM and GSPN methods were respectively used for the reliability modeling and analysis of the main fly-by-wire flight control computer system of Boeing777.Compared with the dynamic GSPN method,the HHRM method adopted static and dynamic reliability modeling methods and combined the flexibility of state-space models and efficiency of combinatorial models.The state space explosion problem caused by GSPN method is avoided by using hierarchical structure.The results of the two methods show that the HHRM method is feasible,efficient and accurate.