基于Backstepping的非仿射非线性系统鲁棒控制

Robust control for nonaffine nonlinear systems based on Backstepping

针对一类不确定非仿射非线性系统的跟踪控制问题,提出一种鲁棒Backstepping控制策略.首先,为利用仿射非线性方法设计控制器,给出一种适用于全局的非仿射非线性近似方法;然后,设计快速收敛非线性微分器以估计复合干扰和获取虚拟信号的微分,进而给出不确定非仿射非线性系统的复合控制器,其中鲁棒项和阻尼项分别用于减少逼近误差和近似方法中动态误差对系统跟踪的影响;最后,通过仿真实验验证了所提出方法的有效性.

A robust Backstepping control strategy is proposed for a class of uncertain nonaffine nonlinear systems. Firstly, a global approximation method is given for uncertain nonaffine nonlinear systems, aiming to design the controller by using affine nonlinear methods. Then, a fast convergence nonlinear differentiator is designed in order to get the differential value of virtual signal and approximate unknown compound disturbances in the uncertain systems. Furthermove, the composite controller structure based on the above design is proposed, in which the robust terms and nonlinear damping term can offset the impact of the approximation errors. Finally, the simulation results show the effectiveness of the proposed method.