Reliability Analysis Of Aircraft Power System Based On Minimum Cut Set

With the rapid development of more electric aircraft and increased electronic and electrical equipment,the reliability requirements of aircraft power system have also been continuously improved.The reliability study of the aircraft power supply network can provide a theoretical basis for aircraft design and maintenance.Firstly,the study statically analyzes the B787 aircraft power grid and establishes a static fault tree model.The Petri net and improved binary decision graph method is used to solve the minimum cut set.The static reliability index of the aircraft power grid is solved by the minimum cut set non-intersection theory.Secondly,the study dynamically analyzes the B787 aircraft power grid and establishes a dynamic fault tree model.The logical operation principle of the time operator is used to solve the minimum cut sequence set.The dynamic reliability index of the aircraft power grid is solved by the method of layered module.The dynamic reliability compared with the static reliability index.In order to verify the correctness of the above theoretical analysis,simulation platform of the B737 aircraft lighting system is constructed.The static and dynamic reliability indexes of the B737 aircraft lighting system is calculated by using the minimum cut set and the minimum cut set method,and compared with the B787 aircraft power grid reliability analysis results.The dynamic reliability index of the B787 aircraft grid obtained by the algorithm in this study satisfies the aircraft airworthiness certification standard,which proves the correctness of the method.The dynamic failure probability is three orders of magnitude lower than the static failure probability.The reliability index satisfies the aircraft airworthiness certification standard by analyzing the static and dynamic reliability indicators of the B737 aircraft lighting system.The dynamic failure probability is the same order of magnitude as the static failure probability.This shows that the power supply redundancy of the B787 aircraft grid is improved,and the reliability is better than that of the B737 aircraft.At the same time,it proves the correctness and applicability of the algorithm.