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

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.

Multi-variable Linear Extended State Observer for a Class of Nonlinear Systems and Its Convergence Analysis

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 frequency domain, the convergence property with respect to the estimation on uncertain dynamics of nonlinear system is analyzed. Furthermore, the estimation error model of uncertain dynamics is deduced in the form of frequency domain. Simulation 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.