Northwestern Polytechnical University, 127 West Youyi Road, Beilin District, Xi'an, 710072, Shanxi, China.
Ansteel Engineering Technology Corporation Limited, 1 Huangang Road, Tiexi District, Anshan, 114021, Liaoning, China.
ISA Trans. 2023 Jul;138:432-441. doi: 10.1016/j.isatra.2023.03.028. Epub 2023 Mar 24.
In this paper, the composite robust control problem of uncertain nonlinear systems with unmatched disturbances is investigated. In order to improve the robust control performance, the integral sliding mode control method is considered together with H control for nonlinear systems. By designing a disturbance observer with a new structure, the estimations of disturbances can be obtained with small errors, which are used to construct sliding mode control policy and avoid high gains. On the basis of ensuring the accessibility of specified sliding surface, the guaranteed cost control problem of nonlinear sliding mode dynamics is considered. To overcome the difficulty of robust control design caused by nonlinear characteristics, a modified policy iteration method based on sum of squares is proposed to solve the H control policy of the nonlinear sliding mode dynamics. Finally, the effectiveness of the proposed robust control method is verified by simulation tests.
本文研究了具有不匹配干扰的不确定非线性系统的复合鲁棒控制问题。为了提高鲁棒控制性能，将积分滑模控制方法与非线性系统的 H 控制结合使用。通过设计一种具有新结构的干扰观测器，可以以较小的误差获得干扰的估计值，用于构造滑模控制策略并避免高增益。在确保指定滑动面可达性的基础上，考虑了非线性滑动模态动力学的保性能控制问题。为了克服非线性特性引起的鲁棒控制设计困难，提出了一种基于求和的修正策略迭代方法，用于求解非线性滑动模态动力学的 H 控制策略。最后，通过仿真测试验证了所提出的鲁棒控制方法的有效性。
