Zhejiang University of Technology
The National Natural Science Foundation of China (General Program, Key Program, Major Research Plan)
针对一类不确定离散时间系统, 提出一种新型两相幂次吸引律, 能够直接反映误差的动态性能. 在吸引律设计中, 将跟踪误差收敛过程划分为两个不同阶段, 且各收敛阶段设计的吸引律幂值不同, 从而增加误差每步收敛的幅度和提高误差收敛速度. 为了有效补偿系统干扰, 构造离散形式的扩张状态观测器, 并基于观测值设计两相幂次形式的离散时间控制器, 提高系统鲁棒性和减小稳态误差. 此外, 推导出跟踪误差的绝对吸引层和稳态误差带的具体表达式, 并给出了最大收敛步数分析, 以此刻画系统稳态和瞬态性能. 仿真结果验证了所提方法的有效性.
In this paper, a novel two-phase power attracting law-based control scheme is proposed for a class of uncertain discrete-time systems, which can directly reflect the dynamic performance of the tracking error. In the design of the attracting law, the convergence process of the tracking error is divided into two different stages with different power values, such that the amplitude of each convergence step and the error convergence speed are both improved. In order to effectively compensate for system disturbances, an extend state observer is designed, and then a discrete-time controller with two-phase power is presented to improve the system robustness and reduce the steady-state error. In addition, to characterize both the steady-state and transient performance, the steady-state error band, the attractive layer and the maximum step size of the tracking error converging into the steady-state error band are derived, respectively. The simulation results are provided to show the effectiveness of the proposed scheme.