针对大射电望远镜(LT)悬索粗调系统为一变结构、非线性、慢时变、大滞后、强耦合、多输入多输出柔性结构系统的特点,提出了一种Fuzzy-PID控制和干扰观测器相结合的控制算法来实现馈源轨迹跟踪策略。这种方法通过构造干扰观测器来预测该柔性结构系统的各种干扰,并根据预测到的干扰信息进行补偿以抑制干扰对系统的影响,同时引入Fuzzy控制算法来自适应整定PID控制器的参数实现具有最佳组合的PID控制。最后,对LT悬索-馈源舱控制系统进行了数值仿真,结果表明该控制算法可以较好地满足馈源系统轨迹跟踪精度要求,同时系统具有较强的适应性和鲁棒性。
Considering the characteristics of variable structure, nonlinearity, slow time-variance, large delay, strong coupling, MIMO and flexible feed system of large spherical radio telescope (LT), a novel control method combining the Fuzzy-PID controller with the disturbance observer is utilized to realize the trajectory tracking of the feed. That is, through estimation of a variety of disturbance by using disturbance observer, the disturbance acting on the flexible structural system can be compensated, and then the effect of disturbance is suppressed. Based on a practical project, an algorithm of fuzzy self-tuning PID control is introduced to approximate optimal control. The simulation results show that the tracking accuracy is much better and the control system has strong adaptability and robustness.