基于Simscape模型的航空发动机系统安全性分析方法

In view of the problem of coupling influence in the system safety analysis of aero-engines, the coupling fault modeling and safety analysis of aero-engines based on Simscape model were studied. Combined with the general characteristics of fault extension in model based safety analysis (MBSA), two ways of fault external expansion and internal fault expansion based on modeling language of Simscape model were analyzed, so as to establish a model considering the coupling faults. Taking the main fuel control subsystem in full authority digital engine control (FADEC) as a research example, formal safety analysis of the independent and coupling fault was conducted. The results showed that the Simscape model of aero-engines system safety analysis based on the system design environment can be used as a common tool for system design and safety analysis, which can ensure the consistency of design and safety analysis. Based on the principle of fault mathematics, the model expansion method and modeling language can flexibly and quantitatively describe the component independency and coupling fault characteristics in different physical domains of the actual system. The safety analysis based on the extended fault model had the advantages of formalization, intuitiveness and objectivity.