CRAN - Campus Sciences
BP 70239 - 54506 VANDOEUVRE Cedex
Tél : +33 (0)3 72 74 52 90 Fax : +33 (0)3 72 74 53 08
Sujet de Thèse : Commande tolérante aux défauts/fautes de systèmes LPV sous contraintes de saturations
Dates : 2017/10/01 - 2020/09/30
Directeur(s) CRAN : Didier THEILLIOL
Description : Fault-tolerant control (FTC) attracts more and more attentions during the recent decades [1]. The objective of FTC approaches is to guarantee the closed-loop system stable and maintain admissible degradation performance in the presence of component malfunctions [2]. In this work, actuator faults are considered. Most of the drawback of FTC approaches proposed in the literature is the absence of considering actuator constraints. Actuator constraints are essential to be considered; especially after actuator stuck failure occurred. The output ranges of remaining fault-free actuators are decreased because some effectiveness is used to compensate constant control input and lost control effectiveness caused by the stuck actuator. Under this condition, actuator saturation is more prone to occurrence so that it is indispensable to analyse stuck compensation under nonlinear representation such LPV form. At the same time, in order to maintain admissible degradation performance, new references are required if the original one is not reachability. To the best knowledge of the authors, there exist minor investigations of reference redesign for post-fault system with considering actuator constraints represented under LPV models. LPV systems can bring a good opportunity to deal with sometimes very restrictive nonlinear approaches that cannot be applied [3]. Some researchers have focused their attention to design FTC strategies to LPV systems [4]. These techniques used the Linear Matrix Inequality that is able to provide good results for LPV models by using the approach of polytopic LPV systems. The research will be considered such framework to solve fault-tolerant control under saturation constraints due to actuator faults/failures. Furthermore, the method is extended to set-point tracking problem where the reachability of original reference can be evaluated. Then, a new optimal reference is computed for the post-fault system if the original one is unreachable under LPV systems.

[1] Zhang Y, Jiang J. Bibliographical review on reconfigurable fault-tolerant control systems. Annual Reviews in Control 2008; 32(2):229–252.
[2] Noura H, Theilliol D, Ponsart J, Chamseddine A. Fault-tolerant Control Systems: Design and PracticalApplications. Advances in Industrial Control, Springer: Dordrecht, Heidelberg, New York, London, 2009.
[3] Briat, C. (2015). Linear Parameter Varying and Time Delay Systems, Analysis, Observation, Filtering and Control. Advances in Delays and Dynamics, vol. 3.

[4] S. Montes de Oca, S. Tornil, V. Puig, D. Theilliol "Fault Tolerant Control Design using the LPV approach", International Journal of Robust and Non Linear Control, vol. 24, n°14, pp. 1969-1988, 2014
Mots clés : Active Fault Tolerant Control, Actuator saturations, (re)-planning trajectory
Département(s) :
Contrôle Identification Diagnostic
Financement : Conacyt