Liste des communications
Real Time Implementation of Grid Connected Wind Energy Systems: Predictive Current Controller
This work, suggests a new control strategy usingFinite-Control-Set Model-Predictive-Control (FCS-MPC) for thecontrol of a wind turbine system (WTS) based on PermanentMagnet Synchronous Generator (PMSG). The consideredcontroller is separated on two parts: FCS-MPC-based on thecurrent control loop for the single switch mode rectifier tooptimally release the maximum wind power, and FCS-MPCbased on the voltage control loop for the voltage source inverterto enhance the THD of grid currents. A wind energy systemprototyping platform was developed and accomplished in thelaboratory, and the experimental results are provided to verifythe performances of the considered FCS-MPC strategies. Voir les détails
Mots clés : Finite-Control-Set Model-Predictive-Control (FCSMPC), Permanent Magnet Synchronous Generator (PMSG), Wind Turbine System (WTS), Maximum Power Point Tracking (MPPT), Grid Connected, Experimental Results
A DC/DC Buck Converter Voltage Regulation UsingAn Adaptive Fuzzy Fast Terminal Synergetic Control
In this paper, an adaptive fuzzy fast terminalsynergetic voltage regulation for DC/DC buck converter isdesigned based on recently developed synergetic theory and aterminal attractor method. The advantages of presentedsynergetic control include the characteristics of finite timeconvergence, insensitive to parameters variation and chatteringfree phenomena. Rendering the design more robust, fuzzy logicsystems are used to approximate the unknown parameters in theproposed controller without calling upon usual modellinearization and simplifications. Taking the DC/DC buckconverter in continuous conduction mode as an example, thealgorithm of proposed synergetic control is analyzed in detail. Allthe simulation results demonstrate the effectiveness and the highdynamic capability of the proposed AF-FTSC control techniqueover the FTSC strategy Voir les détails
Mots clés : synergetic control, fuzzy logic system, terminal technique, finite time convergence, DC/DC buck converter
Comparative study between EKF and Geometrical methods for theAcoustic Emission source localization.
The purpose of this paper is to optimize and apply probabilistic methods and compare the obtained results to geometric method for locating acoustic emission (AE) source in a plate-like structure. The time of arrival (TOA) of the AE waves in each sensor taking into account the uncertainties, was determined by the continuous wavelet transform (CWT). Then the group wave's velocity was calculated by Monte Carlo simulation. As a probabilistic method, the extended Kalman filter (EKF) is used to iteratively estimate the location of AE sources. Experimental results have shown that the probabilistic method estimates thelocation of the pencil lead break better than the geometric method.Experimental tests were performed on a copper plate to validate the comparison of the two approaches performances. Voir les détails
Mots clés : Acoustic Emission (AE), Time of arrival (TOA), Continuous Wavelet Transform (CWT), Monte Carlo simulation, Geometrical method, Extended Kalman Filter (EKF)
Lightweight CNNs-Based Object Detection forEmbedded Systems implementation
Deep Learning algorithms, based on the implementation of Convolutional Neural Networks (CNN), are more and more used in Artificial Intelligence (AI) applications, especially in the image recognition field, like image classification, object detection, segmentation. These algorithms learn from training data a set of parameters to create a model, which is capable of performing a classification task with high accuracy. The most recent models consist of millions of parameters, which make it computationally very exhausting, especially in the field of embedded systems where resources are very limited. Recently, deep learning and computer vision are highly used to realize a fully-autonomous drone and self-driving cars, which does not need human intervention. Computer vision is a field focused on enabling drones to interpret and understand the content of an image or a video using CNNs. This paper focuses on reviewing recent lightweight CNNs architectures used that can be implemented on embedded targets. Voir les détails
Mots clés : Computer vision, Deep Learning, Object Detection, Convolutional Neural Network, lightweight CNN
A survey on deep learning-based object detectionalgorithms for drones
Unmanned Aerial Vehicles (UAVs) are being used in a very large number of applications. Building an intelligent UAVis a very exciting and challenging topic. Recently, deep learning and computer vision are highly used for the purpose of realizing a fully-autonomous drone that does not need human intervention. Computer vision is a field focused on enabling drones to interpret and understand the content of an image or a video using Convolutional Neural Networks (CNNs). This paper focuses on reviewing recent deep learning-based object detection algorithms used for UAVs. We will discuss the most important research papers and techniques which helped improve the object detection state-of-the-art for drones. Finally, we will conclude this reviewing with a description of the main challenges for the application of deep learning for drone-based solutions. Voir les détails
Mots clés : Computer vision, UAV, Deep Learning, Object Detection, Convolutional Neural Network
Optimization of AZO/ZnO/Cu2O Thin Film Heterojunction Solar Cell with Gaussian Defect
In the present article, we report on the simulation study of defected n+-n-p heterojunction metal oxide (MO) thin film solar cell. In the structure, the natural p-type cuprous oxide (p-Cu2O) thin film as an absorber layer is conducted with the natural n-type zinc oxide (n-ZnO) thin film as a buffer layer and a transparent conducting aluminum-doped zinc oxide (n+-AZO) thin film at the front of the n-ZnO buffer layer to verify the function of the window layer. The update xwAMPS version of AMPS one-dimensional simulator has been used to optimize the feasibility of n+-AZO/n-ZnO/p-Cu2O solar cell under air mass AM1.5 illuminations and 300K of temperature. The impact of the Cu2O absorber layer thickness in the n+-n-p heterojunction MO solar cell is investigated and hence, the performance of the n+-AZO/n-ZnO/p-Cu2O structure with gaussian defect is optimized. Voir les détails
Mots clés : Cu2O, ZnO, AZO, Gaussian defect, heterojunction, J-V data, wxAMPS
Study and development of a new process for the treatment and purification of industrial effluents contaminated by metals by electrodeposition
Currently, Electrochemical methods find wide application in the treatment of industrial effluents to reduce their organic matter content, in inorganic sulfur compounds and nitrogen, or in harmful metals for the environment. Electrochemistry is not only applied to wastewater, but also on contaminated soils, incineration residues or sewage sludge wastewater from the metallurgical industry. Electrochemistry has proved its effectiveness, which allowed him to integrate the environmental industry. Environmental electrochemical technologies allow to control pollution, to recycle materials, to carry out the rehabilitation of sites, monitoring (monitors and sensors for gases and liquids), the efficient conversion of energy, the prevention of corrosion, removal of contaminants and disinfection of water. Electrochemical processes can therefore be efficient and economical when properly designed, and they integrate harmoniously with the environmental industry. These processes require compact installations and can thus integrate into existing industrial waste treatment chains. The present work aims so the elaboration of an electrochemical process of treatment and purification of industrial effluents contaminate with metals. Indeed, the use of this technique can allow both the elimination of these metals by electroplating on a cathode, a recovery of metals, a saving of precipitation reagents and a reduction in the amount of sludge to be removed, as well as surface treatments where the applications concern gold recovery, silver, copper, cadmium, nickel, zinc, iron and lead ... etc. The metal that can be recovered in the form of valorizable cathodes, which allows the depollution of the environment. This work requires in-depth studies of design considerations and the development of an electrolytic cell. Voir les détails
Mots clés : electrochemical, environment, pollution
PredictiveControl of a Grid Connected PVSystemsIncorporating Active Power FilterFunctionalities
This paper presents a multifunction operation of adouble stage grid connected photovoltaic system, with insertionthe active power filter (APF) functionalities. This system is usedto compensate the reactive power, suppression harmonicscurrents supply the nonlinear loads and inject the active powerinto grid. Our work is focused on the grid side, a perturbationand observation control is used to reach the maximum powerpoint tracking (MPPT) regardless of solar radiation. On the gridside, a modified instantaneous active and reactive poweralgorithm (P-Q) based on a multi-variable filter (MVF) is usedin order to identify the harmonics currents reference underdistorted source voltage condition, also a modified predictivecurrent control (PCC) algorithm is used to control the sourcevoltage inverter in order to ensure compensate reactive powerand harmonic currents, feed the non linear load and inject thesurplus generated power into the grid. In Matlab/Simulinksoftware, the proposed control scheme is investigated under loadchange and radiation change conditions. Simulation resultsshows that the proposed PCC of the APF guarantees a flexiblesettlement of real power amounts exchanges with the grid with ahigh power factor operation. Furthermore, the grid currentrecovers its sinusoidal waveform with a total harmonic distortion(THD) meet to IEEE-519 standard Voir les détails
Mots clés : Photovoltaic system (PV), activ power filter (APF), Predictive current control (PCC), active and reactive power theory (P-Q), multivariable filter (MVF), total harmonic distortion (THD)
Conception of a friction stir welding tool
Friction stir welding is a new process that allows a solid-state joining technology of metallic components. Applications and development within this approach has incr eased during the last decade. In this process, the geometry of friction tool plays a fundamental role to obtain suitable microstructures in the weld and the heat affected zones, thus it will be then possible to improve the strength and fatigue resistance of the joint. Among the articles related to the friction process, only few have treated the manufacturing process of the tool. In this work, we will focus on this last point. To increase the welding quality and the process reliability, the design of the tool includes a shaft-spring-based system aimed at avoiding premature damage, furthermore to allow the measure of applied friction pressure. Our improved friction tool has then been tested for applied this welding technique on Al-2024 and Al-7075 aluminium alloys sheets. The weld quality has been evaluated by means of a microstructure analysis and micro-hardness measurements. The ability to increase the welding speed, the changes of the crystalline plans orientation in the mixed part of thermo-mechanically affected zone and grains sizes observed in micrographics underline the effect of the pin geometry and its displacement. The micro-hardness curve shows good mechanical properties. Finally, the obtained results show a su ccessful welding with accep table quality and open new interesting perspectives. Voir les détails
Mots clés : Aluminium, conception, Friction Stir Welding, tool, Micro-hardness
Study of 5 % Fe-doped ZnO Powder Nanostructures as Transparent Ceramic for Optical Applications
microstructural properties using X-ray diffraction (XRD) for examined 5% Fe doped ZnO. The ZnO starting pure powder exhibited a hexagonal crystal structure with space group p63mc of ZnO, however with the introduction of 5 % Fe in the ZnO milled powder, the hexagonal ZnO phase remained un-changed, whereas the microstructural parameters were subject to significant variations due to the intro-duction of Fe atoms into the ZnO hexagonal matrix to replace oxygen ones. The size of crystallites and microstrains are found milling time dependent. For the applications of Zinc oxide, Zinc oxide (ZnO) is a potential candidate material for optics applications which has attracted considerable attention over past decades due to its wide potential applications such as ZnO photonic crystal slab, photo catalyst, UV absorption, solar cells, and so on. Voir les détails
Mots clés : ZnO; Microstructure; XRD; Mechanical Alloiyng; Optical Applications