Reliability analysis for multi-component system considering failure propagation and dependent competing failure process

Failure propagation exists widely in complex systems and has great influence on reliability evaluation of systems. A system reliability model considering multiple failure propagation based on the dependent competing failure process is developed in this paper. A multiple failure propagation is explored, namely, acceleration of degradation and intensification of shock. General linear paths with different degradation rates and shock damage are used to describe the soft failure process of components. The mixed shock model and the Markov chain method are used to establish the reliability model of the hard failure process. The discrete probability density function method is used to calculate component failure time. The reliability model of the whole system is derived by utilizing the total probability method. The model is verified by using a Li-ion battery pack as a numerical example, and the corresponding analysis is conducted.