结构滤波器在望远镜主轴控制系统中的应用

摘要

为了提高望远镜控制系统的闭环带宽和动态性能,研究了结构滤波器对控制系统闭环性能的影响.根据望远镜机械跟踪架的弹簧质量模型推导了系统的传递函数,分析了电机和负载转动惯量与谐振频率的关系,设计了基于系统开环频率特性的结构滤波器?将设计的结构滤波器串联入控制回路,用于减小机械谐振的幅值?介绍了结构滤波器的设计方法,以及加入结构滤波器后对控制系统闭环性能的影响?最后,在2 m望远镜跟踪架转台上进行了验证实验?结果表明,加入结构滤波器后系统的闭环带宽由10 Hz提高到了13 Hz,有效地抑制了速度的稳态谐振,提高了望远镜控制系统的速度跟踪性能?得到的实验结果验证了结构滤波器能够有效地提高系统的动态性能.%To improve the closed-loop bandwidth and dynamic performance of control system in a telescope, the effect of structural filters on the closed-loop performance of the control system was researched.According to the spring-mass model of mechanical tracking frame for the telescope, the transfer function of the system was deduced and the relation between the rotational inertias for electrical machines and loads and the resonant frequencies was analyzed.Then, a structural filter was designed based on frequency characteristics of an open-loop system, and it was added into the control loop to reduce the amplitude of mechanical resonance.The design method of the structural filter was introduced and influence of the added structural filter on the close-loop performance of control system was analyzed.Finally, a confirmatory experiment was performed on a rotary table of tracking frame for a 2-meter-high telescope.The experimental result shows that closed-loop bandwidth of the system increases from 10 Hz to 13 Hz after adding the structural filter, which effectively restrains the stable resonance of speed, improves the speed tracking performance of control system in the telescope.These results verify the effectiveness of the structural filter.