Reliability modeling for intermittent working system based on Wiener process

摘要

Intermittent working system (IWS) refers to the system which alternates between working state and storage state. Different from continuous working system, a considerable part of IWS's lifetime is spent in storage state. Temperature, humidity, corrosion and long-term storage in storage state jointly contribute to a non-ignorable part of the degradation of the IWSs. Motivated by this problem, in this paper, a novel reliability model considering both storage degradation and working degradation is developed based on Wiener process. In the proposed model, the distribution of degradation states at the transition points between storage state and working state is included. Further, the IWS whose duration time of storage state and working state are predetermined fixed values is categorized as scheduled IWS and the IWS whose duration time of the two states are random variables is random IWS. Randomness that exists in duration time of each state period as well as the accumulative duration time of each state is analysed and considered. The general degradation model of scheduled IWS and random IWS are obtained and expression of IWS's reliability is derived from the proposed model. Finally, analytical results as well as Monte Carlo simulation results are compared to illustrate the effectiveness of the model.