Optimal periodic switching strategy for a two‐unit warm standby degradation system.

In the traditional switching policy of a standby system, the standby unit is switched to the normal operation state only after the active unit fails. In contrast, in satellite engineering, a new periodic switching strategy is used by technicians in the satellite gyroscope standby system. Due to the performance degradation of the gyroscope in the long‐term operation and standby process, satellites may fail on orbit. For this problem, an operation optimization model is established for a two‐unit warm standby degradation system considering the periodic switching strategy. First, the degradation process of the units is described by a multiphase Wiener process. Second, based on the first‐hitting time theory, the analytic expressions of reliability and mean time to failure (MTTF) of the degradation system are derived. Third, the optimal periodic switching interval is determined to maximize the system MTTF by using the particle swarm optimization algorithm (PSO). Finally, a numerical example of a gyroscope warm standby subsystem is provided to validate the proposed model. [ABSTRACT FROM AUTHOR]