基于BDMP的核电厂蒸汽发生器水位控制系统可靠性评价

Reliability Assessment for Steam Generator Water Level Control System in NPP Based on BDMP

数字化仪表与控制系统(DICS)已广泛应用于核电厂安全/非安全相关的系统中。作为中枢神经系统,DICS的可靠性对核电厂运行过程的操作和维护至关重要。基于蒸汽发生器水位控制系统(SGWLCS)的结构和控制逻辑,采用布尔逻辑驱动的马尔科夫过程(BDMP)方法对系统进行了评价,分别得到可修复系统与不可修复系统随仿真步长增加的累积分布概率(CDP)。通过KB3搭建了BDMP模型,通过蒙特卡罗仿真软件YAMS对搭建的系统进行生产力分析,定量化分析出系统随仿真步长增加的CDP的变化趋势,以此计算系统的失效概率。通过对系统各组件的敏感性分析可直观得到各组件对系统的重要度影响。

Digital instrumentation and control system （DICS） has been widely applied to safety/non-safety systems in NPP. As the central nervous system, its reliability is cru-cial to the operation and maintenances in the process of operation. Based on the struc-tural and control logics of the digital steam generator water level control system （SGWLCS）, the Boolean logic driven Markov process （BDMP） formalism was recom-mended and applied to the assessment of the system. With the increase of simulation steps, the cumulative distribution probability （CDP） of repairable and non-repairable SGWLCS was calculated. The BDMP model was constructed by KB3, and the produc-tivity analysis was performed by the Monte Carlo simulation software YAMS. The tendency of the system CDP used to derive the failure probability with the performance period was assessed in quantitative way. Through the sensitivity of each component of the system, the importance to the whole system of each component can be intuitivelyachieved.