Reliability Analysis Of Aircraft Power System Considering Common Cause Failure

The aircraft power system serves as a direct source of electrical energy for the onboard electrical equipment,and its reliability is an important guarantee for flight safety.In recent years,The civil aviation industry of China has developed rapidly and will enter a period of high-quality development.The high-quality development of civil aviation is inseparable from the safety and reliability of the aircraft,which puts forward higher reliability requirements for the aircraft power system.At present,in civil aircraft,redundant design is usually used to improve the reliability of the aircraft power system.The redundant design of the aircraft power system not only improves the reliability of the system,but also increases the probability of common cause failure of the components in the system.Therefore,this paper analyzes and studies the reliability of the aircraft power system on the basis of considering common cause failure factors.This paper first introduces the basic concepts of reliability,and discusses the reliability analysis methods of common cause failure systems based on the related theories of common cause failures.Then analyze the power supply principle of the B737-800 aircraft power system and common cause failures in the system according to the composition structure of the aircraft power system,and use Bayesian networks and dynamic Bayesian networks to construct aircraft power system reliability model considering common cause failures and aircraft power system reliability model considering common cause failure and maintenance factors.Finally,analyze the influence of common cause failure factors and maintenance factors in the reliability analysis of aircraft power system.The results show a lower reliability of the obtained aircraft power system when the common cause failure factors among redundant components are considered than that without considering these factors,which is more consistent with the actual situation;When the system is under maintenance,the failure rate of the aircraft power system tends to be stable after a period of operation,while in the absence of maintenance factors,the failure rate of the aircraft power system gradually increases with the passage of time.It can be seen that regular maintenance and repair of the aircraft power system can effectively improve the reliability of the system.This paper takes the B737-800 aircraft power system as an example,takes reliability and related theories of common cause failure as guidance,and combines system reliability modeling methods to carry out reliability analysis and research on the aircraft power system,provide a theoretical basis for improving the reliability of the aircraft power system and the in-depth maintenance capability.