Related Experiment Video
Updated: May 14, 2026
08:35
Interactive and Visualized Online Experimentation System for Engineering Education and Research
Published on: November 24, 2021
Active disturbance rejection control for fractional-order system.
Mingda Li1, Donghai Li, Jing Wang
1Engineering Research Institute, University of Science and Technology Beijing, No. 30 Xueyuan Road, Haidian District, Beijing 100083, China. inventorlmd@gmail.com
ISA Transactions
|February 12, 2013
Summary
This study introduces an integer-order control method for fractional-order systems, using active disturbance rejection control (ADRC) to manage complex dynamics and disturbances effectively.
Area of Science:
- Control Engineering
- System Dynamics
- Nonlinear Control
Background:
- Fractional-order proportional-integral (PI) and proportional-integral-derivative (PID) controllers are standard for fractional-order systems.
- These systems present unique challenges due to their complex dynamics.
Purpose of the Study:
- To propose a simplified integer-order control strategy for fractional-order systems.
- To demonstrate the efficacy of active disturbance rejection control (ADRC) in managing fractional-order dynamics.
Main Methods:
- Fractional-order dynamics are treated as a disturbance and actively rejected using ADRC.
- An extended state observer is employed for estimating external, sensor, and parameter disturbances.
- Stability analysis of the ADRC for rational-order models is performed.
Main Results:
- The proposed integer-order ADRC effectively controls fractional-order systems.
- Simulation results confirm the method's performance on three distinct fractional-order systems.
- The extended state observer accurately estimates various system disturbances.
Conclusions:
- Integer-order active disturbance rejection control offers a viable and simplified approach for fractional-order systems.
- The method demonstrates robustness against disturbances and parameter variations.
- This control scheme provides a practical alternative to traditional fractional-order controllers.
Related Concept Videos
01:27Time and frequency -Domain Interpretation of PI Control
Proportional-Integral (PI) controllers are essential in many control systems to improve stability and performance. They are commonly used in everyday devices like thermostats to enhance system damping and reduce steady-state error. When the zero in the controller's transfer function is optimally placed, the system benefits significantly in terms of stability and accuracy.
Acting as a low-pass filter, the PI controller slows the system's response and extends settling times. This requires careful...
Acting as a low-pass filter, the PI controller slows the system's response and extends settling times. This requires careful...
01:21First Order Systems
First-order systems, such as RC circuits, are foundational in understanding dynamic systems due to their straightforward input-output relationship. Analyzing their responses to different input functions under zero initial conditions reveals significant insights into system behavior.
When a first-order system is subjected to a unit-step input, its response is characterized by its transfer function. By applying the Laplace transform of the unit-step input to the transfer function, expanding the...
When a first-order system is subjected to a unit-step input, its response is characterized by its transfer function. By applying the Laplace transform of the unit-step input to the transfer function, expanding the...
01:07Time-Domain Interpretation of PD Control
Proportional-Derivative (PD) control is a widely used control method in various engineering systems to enhance stability and performance. In a system with only proportional control, common issues include high maximum overshoot and oscillation, observed in both the error signal and its rate of change. This behavior can be divided into three distinct phases: initial overshoot, subsequent undershoot, and gradual stabilization.
Consider the example of control of motor torque. Initially, a positive...
Consider the example of control of motor torque. Initially, a positive...
01:18Second Order systems II
In an underdamped second-order system, where the damping ratio ζ is between 0 and 1, a unit-step input results in a transfer function that, when transformed using the inverse Laplace method, reveals the output response. The output exhibits a damped sinusoidal oscillation, and the difference between the input and output is termed the error signal. This error signal also demonstrates damped oscillatory behavior. Eventually, as the system reaches a steady state, the error diminishes to zero.
If ζ...
If ζ...
01:20Second Order systems I
A servo system exemplifies a second-order system, featuring a proportional controller and load elements that ensure the output position aligns with the input position. The relationship between these components is described by a second-order differential equation. Applying the Laplace transform under zero initial conditions yields the transfer function, showing how inputs are converted to outputs in the system.
By reinterpreting the system, one can derive the closed-loop transfer function, which...
By reinterpreting the system, one can derive the closed-loop transfer function, which...
01:26PD Controller: Design
In automotive engineering, car suspension systems often employ Proportional Derivative (PD) controllers to enhance performance. PD controllers are utilized to adjust the damping force in response to road conditions. A controller, acting as an amplifier with a constant gain, demonstrates proportional control, with output directly mirroring input.
Designing a continuous-data controller requires selecting and linking components like adders and integrators, which are fundamental in Proportional,...
Designing a continuous-data controller requires selecting and linking components like adders and integrators, which are fundamental in Proportional,...