无抖振离散滑模输出反馈控制方法及仿真研究

摘要

针对离散时间系统,提出了一种基于多速率采样输出反馈和幂次函数趋近律的离散滑模控制方法;理论分析表明,通过引入幂次函数可消除离散滑模控制系统的抖振;采用多速率采样技术,运用不同采样速率下的系统输出值表示系统状态,实现了仅用系统输入输出采样值完成离散滑模控制器的设计,减轻了控制系统设计的复杂性;仿真结果表明,控制器的输出、切换函数、系统的输出均不存在抖振现象,而且控制系统表现出了良好的动态特性.%This paper presents a new approach for sliding mode control of discrete-time systems based on the power-function reaching law approach together with the multirate output feedback technique. Theoretical analysis shows that. The chattering of discrete sliding mode control systems can be eliminated by introducing the power-function. The system states are expressed by the system output under the different sample rates with using multirate technology, which are used to design the discrete sliding mode controller and the complexity of the whole system can be alleviated. Simulation result states that there is no chattering in the output of controller, the value of switching function, and the output of the controlled system. This algorithm also makes the controlled system achieve excellent dynamic performance.