基于改善因子的单部件不完全维护优化模型

Optimal imperfect maintenance model for one-unit system based on improvement factor

为了描述维护活动对系统的影响,构建了以周期预防为基础的不完全维护优化模型。针对大部分维护活动都难以使系统修复如新的事实,应用新的改善因子描述维护活动的工龄恢复效应,得到系统的维护成本率。假设系统为寿命符合Weibull分布的耗损型部件,分别以维护成本率最小和在一定可靠度水平上的维护成本率最小为目标进行优化,求解出最佳的系统周期预防维护的时间间隔并进行了数值验证。案例研究表明:考虑失效限度的维护策略虽然获得略高的维护成本率,却可以使设备的可靠度保持在预设水平上,并降低突发功能故障的风险。该维护优化模型可以定量地确定最优维护时间间隔,为维护策略的制定提供决策支持。

The influence of the system maintenance on system failure is modeled in an imperfect maintenance model based on periodic prevention.Most maintenance activities cannot restore the system to as good as new.The age restoration effect is described by an improvement factor with the maintenance costs also included in the model.The lifetime of a deteriorating system is assumed to follow a Weibull distribution.The maintenance cost and the cost with failure limit were minimized to get the optimal maintenance interval.A case study shows that maintenance policies with the failure limit result in higher maintenance costs.However,such policies can ensure that the equipment reliability is kept above a predetermined level and the risk of sudden functional failure is low.The model quantitively determines the optimal maintenance interval to provide decision support for system maintenance.