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In this paper a control strategy using backstepping technique for multilevel inverter based active power filter control is developed. Performances comparison between backstepping strategy and PI regulators based methods is provided. Simulation results prove the robustness and accuracy of proposed technique compared with conventional methods.

Having enough knowledge of the basic solar components, including Direct Normal Irradiation (DNI), Diffuse Horizontal Irradiance (DHI) and Global Horizontal Irradiation (GHI), is greatly significant to concentrated solar power (CSP) projects. (DNI), the amount of direct irradiance received on a plane normal to the sun, is of remarkable usefulness to CSP technologies around the world. However, in Tunisia, the field of solar energy generation faces twofold challenges. First, the unique type of solar concentrating collectors works only on global horizontal irradiation (GHI) which is the geometric sum of DNI and DHI. Second, these collectors are available in a limited number of locations.Regarding this additional review of hourly DNI, our approach to the real time assessment of the clear sky DNI gives a good estimation in the worst case the mean absolute error equal to 40 W/m² for hourly values in comparison to the measured data.

Without measuring current and capacitor voltages, SHE based on Newton raphson algorithm is investigated in open loop control of flying capacitor multilevel inverter for determining the best switching angles for balancing capacitor voltages and eliminating certain harmonic orders considering power factor variation. Simulation results show that the proposed method does effectively eliminate specific low order harmonics and the output voltage is resulted in low total harmonic distortion with balanced flying capacitors.

The work develloped in this paper treat the problems of simultaneous actuator and sensor fault estimation for an Air Craft System. The original system can often be modeled as polytopic linear parameter varying (LPV) plants for which some estimation techniques of fault and state still hard to solve. Here, we propose a new approach to design an adaptive observer based on quadratic Lyapunov approach. The solution is described as an optimization problem formulated in terms of Linear Matrix Inequalities (LMI) techniques. A simulation design shows that the new algorithm yields to reliable state estimation and simultaneous fault detection of the LPV model of Air Craft System which illustrate the validation of the proposed method.

Available solar radiation is an important source of renewable energy that determines Tunisia's productivity but has been poorly characterized. Measured solar radiation datasets are generally not available for long periods. This paper studied the method of estimates for solar radiation based on satellite imagery and on the measured data by the national institute of meteorology. Data collected from the year 2015 in three different locations in Tunisia. The objectives of this study are: a) Assess of monthly global solar radiation using data of meteorology for three stations. b) Compare measured data with two different geostationary satellites imagery in order to validate the good estimation of the satellite imagery. c) Reduce the uncertainly of the use of satellite imagery long-term solar resource by validate the estimated data with those measured by the pyranometer from the meteorological station.

In this paper, the problem of fault isolation and detection is treated for a particular class of linear polytopic parameter-varying system (LPV). In this context, an adaptive observer design is formulated for a given polyquadratic Lyapunov function. As a result, new sufficient conditions are given in terms of Linear Matrix Inequalities (LMIs), which guarantee asymptotic convergence to zero of the estimation error, and to detect and isolate actuator faults. A tentative application was made to show the effectiveness of the proposed algorithm.

In this paper a new topology of cascaded H-bridge (CHB) multilevel inverter employing less number of switches, is presented.

This paper deals with the control design of an asymmetrical cascaded multilevel inverter. This structure therefore provides the capability to produce higher voltages at higher speeds with low switching frequency which has inherent low switching losses and high converter efficiency. Selective harmonic elimination(SHE) for asymmetrical multilevel CHB inverter control is proposed. The technique utilized in the estimation of switching angles involves Firefly Algorithm (FFA). Compared to Newton Raphson algorithm (NR), FFA is more robust and entails less computation time. Simulation results prove the effectiveness of FFA technique compared to NR algorithm. The proposed method does effectively eliminate a number of specific low order harmonics, and the output voltage is resulted in low total harmonic distortion. FFA and NR algorithm for asymmetrical cascaded H-bridge nine level inverter control are experimentally tested on a prototype using FPGA.

This paper presents an algorithm of a robust controller used for the stabilization of biped robot walking gait. The robot is described by a kajita's model with norm bounded uncertainties to ensure a more realistic numerical model. The proposed robust dynamic controller relies on the use of predictive control theory (MPC) and the resolution of a convex optimization problem with Linear Matrix Inequalities (LMI) at every sampling period. The generated control law allows a realtime working robot even in rough ground or unknown environment.

In this paper, a comparison between two observers has been made; an adaptive observer and multiobserver for linear time-varying system. This observer has been designed to estimate simultaneously the state space and faults detection (sensors and actors). The convergence of the adaptive observer is implemented under certain condition. An example of a drying blower system is used to show the effectiveness of the proposed observers.

In this work, we propose a novel robust dynamic controller in order to stabilize a walking biped robot with input and output constraints. Firstly, the trajectory of the robot is generated via the Zero Moment Point method based on the resolution of a convex optimization problem with Linear Matrix Inequalities. Then, the tracking of a referential trajectory is insured by the design of an optimal dynamic controller with predictive control theory. The synthesized dynamic controller allows the Lyapunov stability of the robot's walk. Moreover, it ensures the reducing of the overshoot and undershoot of the output signal, difficult to be adjusted by classical methods. This work is validated by a simulation via Matlab of some illustrative examples and results highlight the efficiency of the proposed study.

This work aims to design an optimal dynamic controller to stabilize the walk of a biped robot even in the presence of input and output constraints. In a first time, the robot's trajectory is generated via the Zero Moment Point criterion based on the resolution of a convex optimization problem with Linear Matrix Inequalities. In a second time, the tracking of a reference trajectory is insured by the design of an optimal dynamic controller based on the predictive control theory. The synthesized dynamic controller allows for the Lyapunov stability of the robot's walk. Moreover, it ensures the reducing of the overshoot and undershoot of the output signal that are difficult to be adjusted by classical methods based on solving the algebraic Riccati equation. This study is validated by a simulation via Matlab of some illustrative examples. Results are presented to prove the effectiveness of the proposed work.

The principle purpose of this paper is to integrate the generalized predictive control (GPC) in the new methodologies of synthesis of a PID controller. The GPC control is also integrated in the synthesis of state feedback control; the optimal control problem for the predictive state feedback control is reformulated in terms of linear matrix inequalities (LMIs). The both control theories are applied in the control of a bioreactor system with multi-model representation around different operating points and the obtained simulation results are compared. The advantage of the proposed PID approach is the simplicity of implementation in real-time processing.

The laboratory of a course is considered as a fundamental part of the education and training for engineers and scientists. Remote laboratories are increasingly finding their way into a variety of disciplines. Development and operation of remote laboratory work are specific process in several dimensions (technological, pedagogical, organizational, etc.). We present in this article some typical characteristics of this process. We will limit ourselves to consider the specificities related to communication between the remote user and the laboratory equipment. We will consider also the problems related to planning and access control and we will highlight aspects related to safety and the initialization of the state of a bench for a new experiment starting at distance.