Entity

Time filter

Source Type

Sfax, Tunisia

Koubaa K.,Research Unit ICOS | Feki M.,Research Unit ICOS | El Aroudi A.,Rovira i Virgili University | Robert B.G.M.,University of Reims Champagne Ardenne | Derbel N.,Research Unit ICOS
2010 7th International Multi-Conference on Systems, Signals and Devices, SSD-10 | Year: 2010

In this paper, we are interested in studying the stability of the two-cell DC/DC buck converter. First, this system is described by a discrete nonlinear model in the state space. Next, we design a dynamic time-delayed feedback controller to assure equal distribution of the potential difference between the cells and to achieve a reference current through the load. According to the controller parameters, two cases are treated in this paper. A stability analysis of the system is carried out for each case. These results are confirmed with numerical simulations. ©2010 IEEE.


Hamza R.,Research Unit ICOS | Feki M.,Research Unit ICOS | Derbel N.,Research Unit ICOS | Robert B.G.M.,University of Reims Champagne Ardenne | El Aroudi A.,Rovira i Virgili University
International Journal of Bifurcation and Chaos | Year: 2011

In this work, a zero static error proportional controller for a two-cell DC-DC buck converter is synthesized and analyzed. Under a traditional proportional control scheme, the system presents a constant error of the current supplying the output load. As the proportional feedback gain is increased, the average static error decreases. However, subharmonic oscillations and chaotic behavior emerge beyond successive bifurcations. To achieve zero current and zero voltage static error, we suggest a modification of the traditional proportional controller. By optimizing the feedback gain, the settling time is also decreased. Then, using nonlinear analysis and Lyapunov stability theory, we prove that zero static error is achieved even in the presence of duty cycle saturation. Numerical simulations are presented to confirm our theoretical results. © 2011 World Scientific Publishing Company.


El Aroudi A.,Rovira i Virgili University | Pelaez-Restrepo J.,Rovira i Virgili University | Kaoubaa K.,Research Unit ICOS | Feki M.,Research Unit ICOS | Robert B.G.M.,University of Reims Champagne Ardenne
Proceedings of EPE-PEMC 2010 - 14th International Power Electronics and Motion Control Conference | Year: 2010

A two-cell DC-DC buck converter under a digital time delay feedback controller is studied. Dynamical aspects of this system are illustrated in the time domain and in the parameter space. TDFC is able to widen the stability range of the system while optimizing the velocity of its response. © 2010 IEEE.


Kaoubaa K.,Research Unit ICOS | Pelaez-Restrepo J.,Rovira i Virgili University | Feki M.,Research Unit ICOS | Robert B.G.M.,University of Reims Champagne Ardenne | Aroudi A.E.,Rovira i Virgili University
International Journal of Circuit Theory and Applications | Year: 2012

Multi-cell converters have been developed to overcome shortcomings in usual switching devices. The control system in these circuits is twofold: first, to balance voltages of the switches and second to regulate the load current to a desired value. However, with a purely proportional controller, the system presents a static error. With a PI controller the static error is annihilated, but at the expense of shortening the stability region and increasing settling time. In this work, a zero static error dynamic controller for a two-cell DC-DC buck converter is designed. To achieve zero current error, we propose a generalized scheme of a dynamic controller. Then, using nonlinear analysis and Lyapunov stability theory and bifurcation prediction tools, we prove that zero static error is achieved. The proposed controller outperforms the PI controller in terms of settling time in the presence of saturating effect during the start-up transients. Numerical simulations in the form of time domain waveforms and bifurcation diagrams from switched circuit-based model are presented to confirm our theoretical results. Copyright © 2010 John Wiley & Sons, Ltd.

Discover hidden collaborations