Testability modeling of hydraulic system based on multi-signal flow model

Testability is an important feature for system which is easy to test and diagnose. A system or equipment with good testability can effectively reduce the time of fault detection and isolation, reduce life cycle costs and improve system reliability and security. In view of the importance of the normal operation of the hydraulic system to the safe flight of the aircraft and the difficulty of accurately positioning and troubleshooting the failure of hydraulic system, it is necessary to start the testability design of the hydraulic system of aircraft. Carrying out testability modeling in the design prophase, it can optimize the testability design, reduce the R&D cycle and save the costs of research. The testability design of the aircraft's hydraulic system also plays an important role in the efficiency of the later maintenance. Through analyzing the structure and function of the hydraulic system, this paper simplifies and divides the hydraulic system of the aircraft flaps. On this basis, it builds the Multi-Signal Flow Model of this system, and proves the validity and feasibility of the testability model by a simulation model of the hydraulic system. The research of the paper has certain theoretical significance for the coordination and analysis of the hydraulic system and the multi-system. It also has reference value for the testability design of the hydraulic system.