一种新的模糊滑模控制器设计方法

针对具有较大且不可观测外界干扰的一类不确定系统,提出一种新的模糊滑模控制器设计方法.首先基于模糊滑模控制原理,引入全局快速终端滑模控制,使系统在有限时间内达到稳态;然后构造以李雅普诺夫函数导数的绝对值为补偿的自适应干扰估计项,对外界干扰进行准确估计,进而提出一种双层递阶指数趋近全局快速终端模糊滑模控制器,通过指数趋近率来调节滑模面的动态品质,该控制器能快速收敛到稳定状态,且有效消除控制器的抖振情况;最后通过仿真算例验证所提方法的有效性.

A new design method of fuzzy sliding mode controller

A new design method of a fuzzy sliding mode controller is proposed for a class of uncertain systems with large and unobservable external disturbances. Firstly, based on the principle of fuzzy sliding mode control, global fast terminal sliding mode control is introduced to make the system reach a steady state in a limited time. Then an adaptive disturbance estimation term compensated by the absolute value of the derivative of the Lyapunov function is constructed to conduct an accurate estimation of external disturbances. Furthermore, a double-layer hierarchical and exponential reaching law global fast terminal fuzzy sliding mode controller is proposed. The dynamic quality of the sliding mode surface is adjusted by the exponential reaching law. The controller can quickly converge to a stable state and effectively eliminate the chattering of the controller. Finally, the effectiveness of the proposed method is verified by a simulation example.