Sensitivity Function Based Active Disturbance Rejection Control for the Plant with Unknown Order and Uncertain Relative Degree

The active disturbance rejection control (ADRC) design based on the sensitivity function is studied for the linear time-invariant SISO minimum-phase system with unknown order and uncertain relative degree. It is proved that ADRC can reject the disturbance and guarantee the close-loop stability provided that the relative degree of such plant is bounded.

Download Full-text

The Active Disturbance Rejection Control with a Square-Root Amplifier for Non-minimum Phase System

Proceedings of 2016 Chinese Intelligent Systems Conference - Lecture Notes in Electrical Engineering ◽

10.1007/978-981-10-2335-4_17 ◽

2016 ◽

pp. 175-182 ◽

Cited By ~ 3

Author(s):

Tong Wu ◽

Weicun Zhang ◽

Weidong Li

Keyword(s):

Disturbance Rejection ◽

Phase System ◽

Active Disturbance Rejection Control ◽

Square Root ◽

Minimum Phase ◽

Active Disturbance Rejection ◽

Disturbance Rejection Control

Download Full-text

Control of Dynamic Systems With Nonlinearities and Time Varying Parameters

14th Biennial Conference on Mechanical Vibration and Noise: Dynamics and Vibration of Time-Varying Systems and Structures ◽

10.1115/detc1993-0114 ◽

1993 ◽

Author(s):

Dirk Söffker ◽

Peter C. Müller

Keyword(s):

Dynamic Systems ◽

Disturbance Rejection ◽

Linear Time ◽

Time Varying ◽

Varying Parameters ◽

Linear Time Invariant ◽

Time Variance ◽

Disturbance Rejection Control ◽

Time Varying Parameters ◽

Time Invariant

Abstract The well-known theory of disturbance rejection control and the experience of using a generalized technique with universal fault model for building observers and regulators for the estimation and compensation of disturbances and unmodeled or uncertain effects as well, could be used for controlling dynamic systems with time varying parameters and nonlinearities. Based on a linear time-invariant model the effects of non-linearities and unmodeled dynamics are estimated by an extended observer scheme. Using this information these dynamic effects will be compensated by the developed compensation scheme. Here also different compensation techniques of disturbance rejection control are discussed, compared, and modified. The simulation example of an inverted flexible pendulum shows the efficiency of the method controlling an unstable mechanical system without exact knowledge of structure and parameters of nonlinearity and time-variance.

Download Full-text

Combined feedforward and model-assisted active disturbance rejection control for non-minimum phase system

ISA Transactions ◽

10.1016/j.isatra.2016.04.020 ◽

2016 ◽

Vol 64 ◽

pp. 24-33 ◽

Cited By ~ 37

Author(s):

Li Sun ◽

Donghai Li ◽

Zhiqiang Gao ◽

Zhao Yang ◽

Shen Zhao

Keyword(s):

Disturbance Rejection ◽

Phase System ◽

Active Disturbance Rejection Control ◽

Minimum Phase ◽

Active Disturbance Rejection ◽

Disturbance Rejection Control

Download Full-text

A relative degree one modified active disturbance rejection control for four-tank level control system

International Review of Applied Sciences and Engineering ◽

10.1556/1848.2021.00352 ◽

2021 ◽

Keyword(s):

Disturbance Rejection ◽

Sliding Mode ◽

Tracking Error ◽

Control Unit ◽

Water Levels ◽

Relative Degree ◽

Active Disturbance Rejection Control ◽

Level Control ◽

Active Disturbance Rejection ◽

Disturbance Rejection Control

Abstract This paper deals with the disturbance rejection, parameter uncertainty cancelation, and the closed-loop stabilization of the water level of the four-tank nonlinear system. For the four-tank system with relative degree one, a new structure of the active disturbance rejection control (ADRC) has been presented by incorporating a tracking differentiator (TD) in the control unit to obtain the derivate of the tracking error. Thus, the nonlinear-PD control together with the TD serves as a new nonlinear state error feedback. Moreover, a sliding mode extended state observer is presented in the feedback loop to estimate the system's state and the total disturbance. The proposed scheme has been compared with several control schemes including linear and nonlinear versions of ADRC techniques. Finally, the simulation results show that the proposed scheme achieves excellent results in terms of disturbance elimination and output tracking as compared to other conventional schemes. It was able to control the water levels in the two lower tanks to their desired value and exhibits excellent performance in terms of Integral Time Absolute Error (ITAE) and Objective Performance Index (OPI).

Download Full-text