Reliability Analysis Of Civil Aircraft Redundant Actuator System

The Fly-by-wire system of civil aircraft is carried out by servo actuator system, which reliability is one of the important technical indexes. The reliability of the servo actuator system has directly influence on the reliability and safety of the civil aircraft. Therefore, it's particularly important studying on the method of reliability analysis and design of the servo actuator system.In this paper the method of reliability analysis and design are mainly studied, especially a parallel-working redundant actuation system is designed. Firstly introduce the common reliability modeling method, and with "servo valve no action", take qualitative and quantitative analysis on electric hydraulic steering gear adopting the fault tree, then the reliability index is allocated to the key components. Based on upwards analysis, dissimilar redundant technology is utilized to the servo actuator system, the study of similar redundant technology in the application of the servo actuator system, and a kind of parallel-working dissimilar redundant actuator is put forward, then the dynamic performance under different control mode is simulated. Make a detailed research on redundant management and work out suitable design of the basic algorithm process, involved synchronous technology, signal monitoring and the cross channel data link communication. Finally, Petri nets is introduced to the reliability model of the servo actuator system, then the generalized stochastic Petri nets models are established from the channel level and the system level separately, the simulation results show that the system designed can achieve the reliability of the specified index requirements, and has a very high reliability.