具有动态不确定性互联大系统的分散自适应控制

Decentralized adaptive control for large-scale interconnected systems with dynamic uncertainties

中文关键词  未建模动态  动态面控制  严格反馈  互联大系统  分散自适应控制

英文关键词  unmodeled dynamics  dynamic surface control  strict-feedback  interconnected system  decentralized adaptive control

中文摘要

      对一类具有未建模动态结构相似形的严格反馈非线性互联大系统, 提出一种基于神经网络的分散自适应动态 面控制方案. 该方案引入Lyapunov函数来约束未建模动态, 利用神经网络逼近理论分析中所产生的未知非线性连续函 数. 通过Young’s不等式和三重求和项的分解, 有效地处理了耦合作用项, 并利用动态面控制技术, 实现了系统的分散控 制. 与现有研究结果相比, 所设计的分散控制律中不含有控制增益下界常数. 通过构造的方法, 利用动态面控制设计中 引入的紧集有效地处理了未建模动态和分析中产生的不确定连续函数. 理论分析证明了闭环控制系统中所有信号半全 局一致终结有界, 且跟踪误差收敛到原点的一个小邻域内. 两个数值算例的仿真结果表明所提控制方案的有效性.

英文摘要

      We present a decentralized adaptive control scheme based on neural networks and dynamic surface control for a class of interconnected nonlinear large-scale systems in strict-feedback form with similar structure and unmodeled dynamics. In the designed scheme, unmodeled dynamics is described by using the Lyapunov function method, and neural networks are used to approximate the unknown nonlinear continuous functions which are produced in theoretical analysis. The interconnected terms are effectively dealt with by using Young’s inequality and decomposition of the threefold summation term, and the decentralized control is realized by utilizing dynamic surface control technique. Compared with the existing results, the designed decentralized control laws do not contain the lower bound of control gain. By the constructing method and the compact set introduced in dynamic surface control design, the unmodeled dynamics and uncertain continuous functions generated in the recursive design are effectively handled. By theoretical analysis, the closed-loop control system is shown to be semi-globally uniformly ultimately bounded, with the tracking error converging to a small neighborhood of the origin. Simulation results of two numerical examples show the effectiveness of the proposed scheme.