时变周期性参考输入的自适应重复控制系统设计

摘要

在凸轮研磨加工应用中,为符合特定加工条件,凸轮需要操作在变转速条件,这将使得输入信号变成所谓的时变周期信号,即是位置或角度的周期信号.因此,为降低时变周期信号的跟踪误差,提出了一种基于重复控制理论设计的具有线性时变特性的自适应重复控制器,使得角位移域内的时变周期信号得到衰减.采用自适应重复控制理论将定义在时域内的所有的控制信号转换成定义在角位移域内的信号,以使输入信号变成周期函数.针对直线伺服电机驱动的凸轮加工中心进行了仿真研究,结果表明所提出的控制方案是有效的,提高了系统跟踪精度,大大减小了跟踪误差.%In the cam grind machining applications, cam needs operate in the varying speed condition to meet certain machining condition. This makes the input signals change into time varying periodic signals, I. E. , the periodic signals of the position or angle. Therefore, the adaptive repetitive controller with linear time varying performance based on the repetitive control theory design is proposed, in order to diminish the tracking error of the time varying periodic signals. This suppresses the time varying periodic signals in the angular displacement domain. Using the adaptive control theory, all the control signals defined in time domain are transformed into the signals in the angular displacement domain to make input signal change into periodic functions. For cam machining drive by the linear servo motor, the simulations are performed. The results show the proposed control scheme is effective. The tracking precision of the system is enhanced and the tracking error is greatly diminished.