在频域内提出了线性扩张状态观测器和高增益跟踪微分器的稳定性研究方法.推导出线性扩张状态观测器和高增益跟踪微分器的稳定性条件以及估计精度,可以证明频域内的分析结果与时域内的分析结果一致.根据估计误差计算结果,提出了两种提高估计精度的方法,并通过幅频特性分析和数值仿真验证了两种方法的可行性.

In this paper, we propose a stability analysis method of linear extended state observer (LESO) and high-gain tracking differentiator (HGTD) in frequency domain. The stability conditions and estimation errors are deduced, which correspond with that in time domain. Two methods to improve the estimation precision are proposed according to the derived estimation errors. The feasibility of the two methods are verified by amplitude-frequency characteristics and numerical simulation.