离散滑模预测控制的鲁棒性

Robustness of discrete time sliding mode prediction control

采用单步预测的思想对滑模预测控制算法进行简化,分析其鲁棒性机理,并将它与传统离散滑模控制设计方法的鲁棒性机理进行对比研究,给出了闭环系统的鲁棒稳定性证明。结果表明:传统离散滑模控制方法通过在控制律中引入不确定性上界值以克服不确定因素的影响,虽然能够保证系统的鲁棒性,但同时必然导致过度补偿,从而加剧抖振。而滑模预测控制采用反馈校正与滚动优化相结合的方法以保证系统鲁棒性,从原理上避免了抖振现象。仿真结果验证了理论分析的正确性。

As for discrete time sliding mode prediction control algorithm,its robustness was studied. By using the single-step prediction method,the discrete time sliding mode prediction control algorithm was simplified.The mechanism of its robustness was analyzed thus to prove that the robustness of the close loop system is stable.Compared with the conventional discrete sliding mode control design method,which suffers from serious chattering due to the overshot compensation to system uncertainties,the sliding mode prediction control algorithm combines receding optimization with feedback correction to assure its robustness.So it can avoid chattering phenomenon effectively.The simulation results prove the correctness of theoretical analysis.