一种基于改进趋近律的离散变结构控制方法

Discrete-time variable structure control based on improved approach law

研究了使用离散指数趋近律方法设计的离散时间控制系统中存在的抖振现象。为了减小这种抖振现象,提出了一种改进的离散趋近律设计方法,而且给出了趋近律的参数选择原则。仿真结果表明:在使用该改进趋近律方法设计的离散时间变结构控制器的调节下,系统的运动状态最终趋近于原点,还可使系统状态保持步步穿越切换面,提高了控制系统的鲁棒性。

The chattering of discrete-time variable structure controller designed by discrete exponent reac- hing law is studied. In order to reduce this chattering phenomenon, an improved method about reaching law is presented. Simulation result shows that the discrete-time variable structure controller adopting the improved reaching law, not only makes the control system status approach zero gradually, but also makes it cross the switching surface at every step, and the robust performance of the controller is also improved.