三床型机载制氧系统控制设计与实验验证

Two-bed onboard oxygen generation system is facing the problem of large pressure fluctuation of output gas and high oxygen concentration at low altitude during the practical application process. In order to solve these problems, three-bed onboard oxygen generation system needs to be developed. According to the system control logic, the control mode that the electronic controlled pneumatic servo valve worked circularly was adopted. The control design of three-bed onboard oxygen generation system has been proposed. The control method of segmented regulation was proposed, in which different cycle time was applied depending on the altitude. Under different input pressure and flow conditions, the experiments of the three-bed onboard oxygen generation system were performed to investigate the influence of the cycle time on the oxygen concentration of product gas. The study results show that when the cycle time for low altitude and high altitude is determined to be 9 s and 6 s, respectively, and the segmented altitude is determined to be 3.5 km, the system control design is suitable for the three-bed onboard oxygen generation system, and meets the requirements for the control design of three-bed oxygen generation system.