Analysis and tuning of reduced-order active disturbance rejection control

To reduce the phase lag introduced by extended state observer (ESO), an reduced-order active disturbance rejection control (RADRC) method is recommended. This paper investigates the structure and parameter tuning of RADRC. Firstly, it is shown that RADRC can serve as a general-purpose fixed structure controller because any proper controller with integrator can be realized via an RADRC. Then the relationship between the parameters of an RADRC and those of a full-order linear active disturbance rejection control (LADRC) is analyzed. It is shown that an RADRC with the proper controller and observer gains can obtain similar disturbance-rejection performance as a full-order LADRC. Simulation results demonstrate that any plant that can be controlled by LADRC can also be controlled by an RADRC with a similar disturbance-rejection performance. (C) 2020 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.

Automated summary

This paper introduces a reduced-order active disturbance rejection control (RADRC) method to reduce the phase lag introduced by extended state observer (ESO). The study shows that RADRC can serve as a general-purpose fixed structure controller and achieve similar disturbance-rejection performance as a full-order linear active disturbance rejection control (LADRC). Simulation results demonstrate that any system controllable by LADRC can also be controlled by RADRC with similar disturbance-rejection performance.