一种新型动态故障树分析方法及在液压系统中的应用

发布时间：2018-11-10 07:38

【摘要】：针对静态故障树无法描述液压系统中元件在失效时呈现出的动态性、时序性、冗余性和相关性等动态失效特征,以及现有的动态故障树在求解顶事件失效概率时存在数据爆炸的问题,基于传统静态故障树、T-S故障树及现有的动态故障树的基础上,提出了一种新型动态故障树分析方法,进而提出了新型动态故障树的重要度算法,最后采用新型动态故障树分析方法及其重要度算法对数控机床液压系统进行了可靠性分析。首先,基于静态故障树、现有的动态故障树,提出一种新型动态故障树分析方法。新型动态故障树分析方法在求解过程中,不仅能够得到系统在任务时间内的失效概率,还可得到任务时间内各时间段内的失效概率,为系统在任意时间段内的可靠性定性与定量分析提供依据。通过与传统静态故障树、T-S故障树以及现有的动态故障树分析方法对比,验证了新型动态故障树分析方法的可行性及更广泛的适用性。其次,重要度作为故障树定量分析方法中的重要组成部分,反映基本事件或系统的割集对系统的重要程度。基于所提出的新型动态故障树分析方法的基础上,提出新型动态故障树的概率重要度、关键重要度算法,分别从概率重要度、关键重要度的物理意义出发,描述了具有动态失效特征的基本事件的重要度,为系统的可靠性定量分析提供依据。通过与传统静态故障树、T-S故障树的重要度算法对比,验证了所提重要度算法的可行性。最后,数控机床是装备制造业的工作母机,其可靠性问题已成为制约机械装备制造行业发展的关键共性问题,将新型动态故障树分析方法及其重要度算法应用到数控机床液压系统的可靠性分析中,求解出液压系统失效时顶事件的失效概率及各个基本事件的概率重要度和关键重要度,为数控机床液压系统的可靠性提升、故障诊断和基于可靠性的状态维修提供依据。
[Abstract]:The static fault tree can not describe the dynamic failure characteristics of components in hydraulic system, such as dynamic, sequential, redundancy and correlation. And the existing dynamic fault tree has the problem of data explosion in solving the failure probability of top event, based on the traditional static fault tree, T-S fault tree and the existing dynamic fault tree. In this paper, a new dynamic fault tree analysis method is proposed, and then the importance algorithm of the new dynamic fault tree is proposed. Finally, the reliability analysis of the hydraulic system of NC machine tools is carried out by using the new dynamic fault tree analysis method and its importance algorithm. Firstly, based on the static fault tree and the existing dynamic fault tree, a new dynamic fault tree analysis method is proposed. The new dynamic fault tree analysis method can not only obtain the failure probability of the system in the task time, but also obtain the failure probability in each time period of the task time. It provides the basis for the qualitative and quantitative analysis of the reliability of the system in any time period. Compared with the traditional static fault tree, T-S fault tree and the existing dynamic fault tree analysis method, the feasibility and wider applicability of the new dynamic fault tree analysis method are verified. Secondly, as an important part of the fault tree quantitative analysis method, importance degree reflects the importance of the basic event or the cut set of the system to the system. Based on the new dynamic fault tree analysis method, the probabilistic importance degree and the key importance algorithm of the new dynamic fault tree are proposed, which are based on the physical meaning of probability importance and critical importance respectively. The importance of the basic events with dynamic failure characteristics is described, which provides the basis for the quantitative analysis of the reliability of the system. Compared with the traditional static fault tree and T-S fault tree, the feasibility of the proposed importance algorithm is verified. Finally, the CNC machine tool is the working machine of the equipment manufacturing industry, and its reliability has become the key common problem that restricts the development of the machinery and equipment manufacturing industry. The new dynamic fault tree analysis method and its importance algorithm are applied to the reliability analysis of the hydraulic system of NC machine tools. The failure probability of the top event and the probability importance and the critical importance of each basic event are solved. It provides the basis for improving the reliability, fault diagnosis and condition maintenance based on reliability of the hydraulic system of NC machine tools.
【学位授予单位】：燕山大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TH137

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