High Reliability Of The Aircraft Engine Fadec Software System Technology Research

With the development of Aeroengine control technology, reliability of Full Authority Digital Electronic Control (FADEC) becomes more and more important. So, in the design of highly reliable FADEC system, it is greatly necessary to enhance Research & Development of Fault-Tolerant software system. In this paper, software technique applied to highly reliable FADEC system is studied. The FADEC system consists of hardware layer based on Similarity Redundancy technique and software layer based on Dissimilarity Redundancy technique.This thesis proposes a new architecture of FADEC system, which is comprised of hardware layer based on Similarity Redundancy technique and software layer based on Dissimilarity Redundancy technique. On the base of this new architecture of FADEC system, the framework of Fault-Tolerant Software system is constructed. Then, two Fault-Tolerant-orient Real-Time Operating System (RTOS), which are tested as flight critical software applications and reliable, are presented. In addition, the synchronization between the two computers in FADEC system, which includes synchronization of Real Time Clock (RTC) and synchronization of task layer, is designed. Furthermore, Real-time scheduling algorithms and Fault-Tolerant Real-time scheduling algorithms are introduced, and applicability of the Fault-Tolerant Real-time scheduling algorithms in FADEC is discussed.In order to achieve highly reliable application program layer, applicability and availability of Ada program language is analyzed. At last, a new software voting mechanism is introduced.