针对一类非线性系统的多变量线性扩张状态观测器及其收敛性分析

摘要

For a class of nonlinear uncertain systems, a multi-variable extended state observer (MVLESO) is constructed, and it is employed to estimate the uncertain dynamics of nonlinear system in real time. By means of the analysis method in fre-quency domain, the convergence property with respect to the estimation on uncertain dynamics of nonlinear system is ana-lyzed. Furthermore, the estimation error model of uncertain dynamics is deduced in the form of frequency domain. Simu-lation results show that the as-built MVLESO can accurately estimate the current uncertain dynamics in nonlinear systems. This feature lays a foundation for the effective implementation of MVLESO-based robust control scheme.%针对一类非线性不确定系统,构造了一种多变量线性扩张状态观测器(Multi-variable linear extended state observer, MVLESO),用于实时估计非线性系统的不确定动态。采用频域分析方法,剖析了所构造的MVLESO 在非线性系统不确定动态估计方面的收敛性,并推导出不确定动态的频域估计误差模型。仿真结果表明,所设计的MVLESO 可以较为精准地估计出非线性系统当前的不确定动态,该特性为基于MVLESO 鲁棒控制方案的有效实施奠定了基础。