基于可用度的预防维修和均值控制图联合优化模型

针对高可用度要求的生产系统(即可修复系统,以下简称系统),提出一种以单位时间成本为约束,可用度最大化为目标的预防维修和均值控制图联合优化模型。首先,考虑到系统运行存在受控、失控两种状态以及均值控制图两类错误(漏报警和误报警)发生的概率,在完美维修假设前提下,构建了4种系统运行(更新)情景(S1~S4)。然后,建立了每种更新情景的可用度和经济模型,并在此基础上建立了系统的可用度目标函数和经济约束函数,以实现单位时间成本约束条件下预防维修和均值控制图联合优化的系统可用度最大化目标。针对所建立的联合优化模型,通过实例对比验证了模型的有效性,并利用遗传算法对决策变量进行优化,实例优化结果表明,该模型能够有效提高系统可用度,并能降低系统成本。最后,通过正交试验、回归分析等方法对模型进行了参数的灵敏度分析。

Joint optimization model of preventive maintenance and mean control chart based on availability

A joint optimization model of preventive maintenance and mean control chart was proposed for high availability production system(repairable system, hereinafter referred to as system),which was constrained by unit time cost and aimed at maximizing availability. First, considering the two states of controlled and out of control in the system operation and the two types errors(missing alarm and false alarm) of mean control chart, four system operation(renewal) scenarios(S1~S4) were constructed on the premise of perfect maintenance. Then, the availability model and economic model of each scenario were constructed. On the basis of the above, the availability objective function and economic constraint function of the system were established to obtained maximize the system availability by joint optimizing preventive maintenance and mean control chart under the constraints of unit time cost. The effectiveness of the model was verified by an example comparison, and the genetic algorithm was used to optimize the decision variables. The example optimization results show that the joint optimization model can effectively improve the availability of the system and reduce the system cost.Finally, the sensitivity of the model was analyzed by orthogonal test and regression analysis.