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International audience; In this paper, a high-gain interval observer is proposed for a class of partially linear systems affected by unknown but bounded additive disturbances term and measurements noise. The proposed observer is based upon a classical high-gain structure from which an interval observer for the system is designed. The proposed interval observer is designed based on the suitable change of coordinates which ensure the cooperativity of the system. To prove the effectiveness of the proposed approach, two numerical examples are provided and the corresponding simulation results are presented.

This paper develops a Super-Twisting Algorithm controller via a nonlinear disturbance observer for a DC motor system subject to matched and unmatched uncertainties. The proposed controller is based upon a novel Nonlinear Disturbance Observer structure which uses the concept of total disturbance estimation in order to estimate simultaneously the matched and the unmatched uncertainties in the system. This estimation is incorporated then in a composite observer based controller where the stability analysis is given. Simulations results illustrate the effectiveness of the proposed controller compared to other some existing control designs and show its advantages in terms of disturbance rejection, nominal performance recovery and chattering reduction.

In this paper, a time varying disturbance observer subject to sampled data's measurements is proposed for a class of non-linear systems. The proposed observer combines the advantage of a high gain structure in terms of convergence speed and an output predictor which remains continuous between the sampling times. The exponential convergence of the proposed observer is proved using a Lyapunov function adapted to impulsive systems.

In this paper, a passive fault tolerant control strategy carried out under the concept of higher order sliding mode control is developed for the diesel engine air path. The proposed fault tolerant strategy incorporates a Super-Twisting algorithm controller which handles parametric uncertainties and actuator faults. In this paper we consider two types of actuator faults, additive and loss-of-effectiveness faults. Theoretical results on the convergence of the proposed controller based on the Lyapunov theory are presented. The simulations of the proposed controller on a recently validated experimental air path diesel engine model show good results under actuator faults conditions even in the presence of parametric uncertainties.

This paper investigates sliding mode control framework. An extension of Super-Twisting Algorithm (STA) is designed for the Diesel engine air path to achieve fault-tolerance. The results obtained in its comparison with the adaptive sliding mode controller (ASMC), showed good performances for actuator fault-accommodation even in the presence of uncertainties on model parameters and the improvement of the chattering phenomenon.

This paper investigates second order sliding mode control. The use of the super twisting algorithm for the combustion engine air path is to achieve fault-tolerance and to enhance the chattering phenomenon. Comparing to the adaptive sliding mode controller (ASMC), the obtained results showed good performances for actuator fault-accommodation even in the presence of uncertainties on model parameters.

The paper develops a sliding mode controller via nonlinear disturbance observer for diesel engine air path system subject to matched and unmatched disturbances. The proposed controller is based upon a novel nonlinear disturbance observer (NDO) structure which uses the concept of total disturbance estimation in order to estimate simultaneously the matched and the unmatched disturbances in the system. This estimation is then incorporated in a composite controller which alleviates the chattering problem and maintains the nominal performance of the system in the absence of disturbances. Simulations results of the proposed controller on a recently validated experimental air path diesel engine model show that the proposed methods exhibit a better performances comparing to the baseline SMC in terms of reducing chattering and nominal performances recovery.

For modern Diesel engines, accurate fuel-air ratio AFR and Exhaust Gas Recirculation (EGR) rates control is important for manufacturers to face a more restrictive legislation levels. To fulfill the requirements, hardware devices such (EGR) and Variable Geometry Turbochargers (VGT) valves have been introduced, and sophisticated control algorithms were designed. The main objective of the air path controller is to regulate in the intake manifold the AFR ratio and the EGR fraction rates to their desired values. Earlier EGR PID controllers needed a fastidious and time consuming calibration step for each engine operating point. Nonlinear control algorithms has quickly appeared as a promising way to provide an efficient air path controllers, since they don't need a calibration step. The main drawback of such controllers is coming from the fact that they are based upon a diesel engine model which handles parameters uncertainties and signal measurements errors, that affects the control performance. In this paper we propose a novel control scheme for controlling the diesel engine air path. Control design is carried out under the sliding mode framework. The proposed controller has been tested on the Jankovic Tubocharged Diesel Engine (TDE) model. To demonstrate the robustness of the proposed controller, simulation results showing the tracking of the compressor flow W c and the exhaust manifold pressure p 2 variables are presented.