一种新的约束变速趋近律离散滑模控制方法

考虑惯性执行器输出速度有限的实际,引入趋近律变化速率的控制函数,设计了一种新的无抖振离散滑模变速趋近律算法. 首次提出了通过设计趋近律变化速率来构造离散滑模趋近律的思想,使得控制器的物理意义更加明显,设计更加灵活和简单.对于标称系统, 该算法可以使切换函数在有限时间内快速无抖振地收敛至零;对于满足匹配条件的不确定系统,切 换函数能够收敛至与不确定性及控制参数相关的某一数值,通过设置控制参数,可使这一数值任意小.

A New Discrete-time Sliding Mode Control Method Based on Restricted Variable Trending Law

A new chattering-free variable trending law for discrete-time sliding mode control is designed. On account of actual controller of inertial system where the velocity of output is limited, the function of varying speed of trending law is introduced. A novel idea is firstly presented that through designing the acceleration of trending law the expected trending law is constructed to make the controller's physical meaning distinct, and the design of controller more flexible and easier. As to the nominal system, the trending law can make the value of switch function reach zero in finite time without chattering. For uncertain system satisfying matching condition, this trending law can make the value of switch function monotonously reach a certain value, which is related with external disturbance and can be arbitrarily small by designing the parameter of controller.