scholarly journals Fractional-Order Control of a Nonlinear Time-Delay System: Case Study in Oxygen Regulation in the Heart-Lung Machine

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
S. J. Sadati ◽  
A. Ranjbar Noei ◽  
R. Ghaderi
Keyword(s):  
Time Delay ◽  
Fractional Order ◽  
Delay System ◽  
Oxygen Regulation ◽  
Time Delay System ◽  
Fractional Order Control ◽  
Heart Lung Machine ◽  
Lung Machine

Robust Fractional Order Proportional Integral Control for Large Time-Delay System

2014 ◽  
Vol 716-717 ◽  
pp. 1614-1619
Author(s):  
Rui Hao Xin ◽  
Chun Yang Wang ◽  
Xue Lian Liu ◽  
Ming Qiu Li ◽  
Duan Yuan Bai
Keyword(s):  
Time Delay ◽  
Fractional Order ◽  
Delay Time ◽  
Large Time ◽  
Delay System ◽  
Order System ◽  
Time Delay System ◽  
Proportional Integral ◽  
Integral Controller ◽  
Proportional Integral Controller

In this paper, a new control method for large time delay system is proposed. Firstly, the decreasing time delay controller is used to remodel large delay time plant into small delay time plant. Then, a fractional robust proportional-integral controller (FOPI) is designed, using the phase margin and cut-off frequency at a specified point in the Bode plot of flat robust conditions, to guarantee the desired control performance and the robustness of the high order system to the gain order system. For comparison between the fractional order proportional integral controller and the traditional integer order PID (IOPID) controller, the IOPID controller is also designed following the same proposed tuning specifications. The simulation results indicates that the both designed controllers work efficiently. Furthermore, the FOPI controller makes the large time-delay system get better control effect, the system has high robustness, adaptive ability and anti-jamming ability.

scholarly journals Fractional-Order Controller Design for Oscillatory Fractional Time-Delay Systems Based on the Numerical Inverse Laplace Transform Algorithms

2015 ◽  
Vol 2015 ◽  
pp. 1-10
Author(s):  
Lu Liu ◽  
Feng Pan ◽  
Dingyu Xue
Keyword(s):  
Time Delay ◽  
Laplace Transform ◽  
Fractional Order ◽  
Control Method ◽  
Delay System ◽  
Inverse Laplace Transform ◽  
Delay Systems ◽  
Time Delay System ◽  
Numerical Inverse Laplace Transform ◽  
Fractional Order Controller

Fractional-order time-delay system is thought to be a kind of oscillatory complex system which could not be controlled efficaciously so far because it does not have an analytical solution when using inverse Laplace transform. In this paper, a type of fractional-order controller based on numerical inverse Laplace transform algorithm INVLAP was proposed for the mentioned systems by searching for the optimal controller parameters with the objective function of ITAE index due to the verified nature that fractional-order controllers were the best means of controlling fractional-order systems. Simulations of step unit tracking and load-disturbance responses of the proposed fractional-order optimalPIλDμcontroller (FOPID) and corresponding conventional optimal PID (OPID) controller have been done on three typical kinds of fractional time-delay system with different ratio between time delay (L) and time constant (T) and a complex high-order fractional time delay system to verify the availability of the presented control method.

Sign in / Sign up

Export Citation Format

Share Document