时滞系统自抗扰滑模控制

Active Disturbance Rejection Sliding Mode Control for Time-Delay Systems

针对含输入端未知时延的时滞系统,利用坐标变换设计了三阶非线性反馈扩张状态观测器。扩张状态观测器能够同时估计变换后的系统状态和输入端总扰动信号,非线性反馈具有快速收敛性。通过对时延环节的一阶近似,时滞系统被转化为带有未知函数的二阶非线性不确定性系统的输出反馈控制问题。在此基础上,设计基于跟踪微分器和扩张状态观测器的二阶滑模控制器,实现了输出信号的快速精确跟踪。数值仿真结果验证了所提出控制算法的有效性。

Aiming at the time-delay systems with uncertainty,this paper designs a third-order nonlinear feedback extended state observer(ESO) by using the coordinate transformation.The ESO can estimate both the system states and the total disturbance signal,and the nonlinear feedback has fast convergence.By the first-order approximation of the time-delay,the output feedback control problem of the time-delay system is transformed into controlling the second-order nonlinear uncertain system with unknown function.On the basis of the tracking differentiator(TD) and the designed ESO,the second-order sliding mode controller(SMC) is designed to realize the fast and accurate tracking of the output signal.The numerical simulation results verify the effectiveness of the proposed control algorithm.