考虑维修优先权的多状态冷储备系统可靠性模型

Reliability Analysis of Multi-state Cold Standby System with Repair Priority

针对多状态两部件冷储备系统存在多类维护方式的情况,假设系统中的单维修台能够根据部件状态提供保养和维修两类服务,其中维修具有更高的优先级。采用连续Phase-type分布代替指数分布等典型分布,描述工作部件在不同性能水平的停留时间、维修台保养和维修时间。利用矩阵解析方法获得了系统稳态概率,推导出系统稳态可用度、系统工作时间、系统平均停机间隔时间、维修台故障件到达率和系统故障率等参数的解析表达式。通过算例验证了模型的正确性和适用性,演示了保养和维修速率对系统各可靠性参数的影响。研究结果表明,利用Phase-type分布对多状态系统开展可靠性解析建模,能够在确保良好解析特性的同时,有效提升模型的描述能力,从假设条件环节保证模型具有更强的通用性。

The maintenance mode of a multi-state cold standby system with two identical units is studied. According to the states of units, the single repair facility provides preventive maintenance and corrective maintenance, and the corrective maintenance has a higher priority. The residence time in the different performance levels of the operational unit, the preventive maintenance time and the corrective mainte- nance time are assumed to follow continuous Phase-type distribution, instead of exponential distribution or others typical distributions. The stationary distribution is built by using matrix analytic methods ; and sev- eral performance measures of interest, such as the system stationary availability, operational time, mean time between system halt, failure arrival rate of repair facility and system failure rate, are obtained. Fi- nally, the validity and applicability of the model are verified by numerical applications; and the influ- ences of the preventive maintenance rate and the corrective maintenance rate on the system reliability measures are demonstrated. The study shows that the modeling of system reliability by Phase-type distri- bution can ensure the better analytical property of model, improve the description ability of model, and make the model have strong universality under the condition of some assumptions.