Dynamic Mode Transfer Scheduling for Degrading Standby System Considering Load-Sharing Characteristic

For safety-critical industrial systems, standby redundancy is widely applied to guarantee safety requirements. With the advancement of sensing technology, real-time system reliability evaluation can be executed to prevent failures, for which the load-sharing characteristic has to be considered because multiple components jointly accomplish the mission. In this article, a novel methodology is proposed to online assess the reliability and optimize the mode transfer scheduling of the degrading standby system considering the load-sharing characteristic. First, the stepwise drifted Wiener process is invoked to characterize the component degradation process. Then, to deal with the process and measurement noise, the monitored degradation data are processed online to update the component degradation state and rate, based on the particle filter. Besides, a Monte Carlo method involving the closed Newton-Cotes quadrature rule is employed to quantify the real-time system reliability. Finally, the mode transfer scheduling of standby components is optimized online to maximize the system reliability at mission time. A numerical example and a case study referring to the aircraft hydraulic system are presented to demonstrate the effectiveness of the developed methodology.