具有控制时滞的离散系统的无抖振滑模控制

Chattering-free sliding-mode control for discrete systems with time-delay

中文关键词  离散系统  时滞系统  滑动模态  无抖振  变结构控制

英文关键词  discrete systems  time-delay systems  sliding mode  chattering-free  variable structure control

中文摘要

      研究含时滞的线性离散系统的变结构控制问题. 首先将之简化为不含时滞项的线性离散系统. 然后对简化系统提出一种新的无抖振滑动模态控制算法. 该算法使滑模控制分为两个阶段，当系统轨迹在滑模某邻域以外时, 利用传统的到达控制律使系统状态轨迹单调趋近滑模面; 当系统轨迹进入该邻域内, 无抖振控制律使其轨迹一步到达滑模面. 该控制律有效地削除了由离散系统解轨迹的不连续性产生的抖振现象. 仿真结果表明了这种方法的有效性.

英文摘要

      This paper considers the variable structure control for linear discrete systems with time-delay. The original discrete system with time-delay is simplified to a linear discrete system without time-delay. A new chattering-free slidingmode control strategy is designed for this simplified discrete system. The control algorithm divides the control process into two phases. When the system trajectory is outside of the given neighborhood, the conventional reaching-control law is used to drive the trajectory monotonically toward the switching surface. When the trajectory is inside the neighborhood, the chattering-free control law drives the trajectory to the switching surface precisely in one step. This control algorithm eliminates the sliding-mode chattering caused by the discontinuity of the discrete system. The numerical simulation validates the proposed approach.