工程机械复杂系统可靠性设计的模糊故障树方法

Fuzzy fault tree method for reliability design of complex system in engineering machinery

针对工程机械系统结构复杂且故障特征和原因具有模糊性的特点,将模糊集引入其故障树分析当中,并确定了模糊故障树分析的步骤、原则与方法。通过对工程机械典型发动机系统的功能结构和故障判据进行分析,建立了工程机械某典型发动机系统的模糊故障树,应用模糊数学理论对其进行了模糊故障分析,并应用模糊重要度分析的中值法对重要度进行了计算。分析结果表明,该方法可以较好地解决故障树分析中部分事件故障判据及数据的模糊性问题,为工程机械复杂系统的可靠性设计提供了有价值的参考。

As the system structure of the engineering machinery is complex,and its faults and causes are featured with fuzziness,the fuzzy set was introduced into its fault tree analysis,and then the steps,principles and methods for fault tree analysis was determined.Through analyzing the functional structure and fault criterion of the typical engine system of the engineering machinery,a fuzzy fault tree for certain typical engine system was established.The fuzzy fault analysis was carried out by applying the fuzzy mathematics theory,and the calculation was conducted by using the reliability analysis with fuzzy fault rate and the median method of fuzzy significance analysis.The analysis result indicates that this method can solve the fuzziness problem of failure criterion and data of part events in fault tree analysis,providing the reliability design of the complex system in the engineering machinery with a valuable reference.