On design analysis of linear active disturbance rejection control for uncertain system

It has been shown that the active disturbance rejection control (ADRC), first proposed by Han Jingqing, is very an effective approach to control the uncertain system, whether the plant is linear or nonlinear, time-varying or time-invariant. This paper has quantitatively presented the relation between the observer bandwidth of LESO and the controller's sampling-period in theory. Moreover, it is proven that the shorter the sampling-period, the higher the control degree of accuracy is for the same plant, and the smaller the plant's time-scaling, the larger the closed-loop control error is for the same sampling-period of controller by simulation. In general, this paper will contribute to improving specific ADRC based controller design and tuning for researchers and practice engineers. © 2014 SERSC.