等周期预防性维修策略是一种常见的维修策略，具有实施简单的特点。针对等周期预防性维修策略优化建模粒度过大，且鲜有考虑故障差异（预防性维修对不同故障维修效果存在差异性）等问题，本文以元动作单元为研究对象，将其故障分为损伤故障和本质疲劳故障，考虑预防性维修对这两类故障维修效果存在的差异性，以混合故障率模型描述不完全预防性维修效果，建立了元动作单元的等周期不完全预防性维修策略优化模型，并给出了模型的优化求解算法。最后，通过数值分析对模型的有效性进行了验证，分析了不同维修成本对最优维修成本率以及最优维修策略的影响。研究结果表明：不考虑预防性维修效果差异性会低估元动作单元的维修成本率；不同类型维修成本以及故障类型的占比对元动作单元最优维修策略的制定有着显著的影响。

The equal-cycle preventive maintenance strategy is a common maintenance strategy, which has the characteristics of simple implementation. Aiming at the problem that the optimization modeling granularity of the The equal-cycle preventive maintenance strategy is a common maintenance strategy, which has the characteristics of simple implementation. Aiming at the problem that the optimization modeling granularity of the current equal-cycle preventive maintenance strategy is too large, and fault difference (the difference of preventive maintenance effects on different failures) is rarely considered, this paper takes the meta-action unit as the research object, divides unit failures into damage failures and intrinsic fatigue failures, and considers the difference of preventive maintenance effects on these two types of failures. The hybrid failure rate model is used to describe the imperfect maintenance effect, and an optimization model for equal-cycle imperfect preventive maintenance strategy is developed. Finally, numerical analysis is performed to verify the effectiveness of the proposed model and to analyze the influence of different maintenance costs on the optimal maintenance cost rate and the optimal maintenance strategy. It was shown that the maintenance cost rate of the meta-action unit would be underestimated without accounting for the difference of preventive maintenance effects; the different types of maintenance costs and the proportion of failure types have a significant impact on the formulation of the optimal maintenance strategy for the meta-action unit.

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国家自然科学基金项目（面上项目，重点项目，重大项目）