分层结构热备冗余系统的可靠性分析

热备冗余结构在安全苛求系统中应用广泛．智能化输入输出模块和逻辑处理模块的分离形成了分层结构，层内两个模块相互热备，层与层串联后实现系统功能．采用Markov分析方法，考虑模块失效率和维修率，对分层热备冗余系统的可靠性进行了研究．按照优先恢复系统功能的维修策略建立了系统状态转移图，并由此得出了系统可靠性计算方法．依据仿真计算结果，不同模块的失效率和维修率对系统可靠性的影响程度相似，低优先级修复的模块对系统可靠性的影响程度增大．

Reliability analysis of layered structure hot standby redundancy system

The hot standby redundancy structure has been wide used in safety critical system. The separation of intelligentized input output module,and logic processing module results in the layered structure. Two modules in the same layer are hot standby one another and the layers in series work,so it fulfills the system function. Using the Markov analysis method and taking account of the module failure ratio and maintenance ratio, we analyzed the reliability of layered hot standby redundancy system. We designed the state transition diagram according to the maintenance strategy of first resuming the system function,so reached the system reliability formula. In accordance with the emulation result, the influences of the different modules failure ratio and the maintenance ratio on system reliability are similar, and the influence of the module which has a low maintenance priority on system reliability increases.