A Reliability Modelling Method for Aircraft Electrical Power System Based on Probability Network

As aircraft electrical power system (AEPS) is critical for flight safety, a system-level reliability modelling method for large complex AEPS is proposed with a typical power system as illustration. The modelling method concludes two parts: first, based on the data structure of stack, a depthfirst search algorithm for solving the minimal path sets from each power source node to its sink nodes (which correspond to power supply bus in AEPS) is developed first; and then on the basis of Bayesian network theory, a reliability model construction algorithm for AEPS is proposed by transforming all these minimal path sets into an equivalent probability network. Finally, the power supply reliability of the typical power system is evaluated by using the existent traditional method and the new proposed method separately. The calculation results show that, compared with the traditional method, the new reliability model not only can be used to compute the power supply reliability of each sink node exactly and faster, but also has the advantage of analyzing the dependency of the components in AEPS.