含高阶干扰的非仿射非线性系统自适应跟踪控制

Adaptive tracking control for nonaffine nonlinear system with high-order disturbances

本文考虑了一类带有高阶干扰和未知参数的非仿射非线性系统的自适应跟踪控制问题.为了提高系统的抗干扰性能,首先设计了扩张状态滤波器估计系统受到的高阶干扰,并把干扰估计值引入到控制器中.其次,在每一步递推设计中,为了避免backstepping方法固有的"微分爆炸"问题,引入滑模微分器估计虚拟控制律的微分,进而提出了一种新的自适应控制策略.借助Lyapunov函数理论方法分析了闭环系统的稳定性,即在所提控制策略作用下,可保证闭环系统所有信号是一致最终有界的.最后,利用MATLAB仿真验证了方法的有效性.

In this paper, the problem of adaptive tracking control is investigated for nonaffine nonlinear system with high-order disturbances and unknown parameters. In order to enhance the anti-disturbance performance of system, firstly, a high-order observer is designed to estimate the unknown disturbances, and the disturbance estimate value is introduced into controller. Secondly, in order to avoid the"explosion of complexity"problem, a sliding mode differentiator is introduced in each step and a novel adaptive control scheme is proposed. It is proven that the closed-loop system is stable and all signals in the closed-loop system is uniformly ultimately boundedness via Lyapunov function theory. Finally, a MATLAB simulation is employed to demonstrate the effectiveness of the proposed method.