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in this paper, a simple and low cost single phase seven-level inverter for PV solar pumping system is proposed. The system consists of a dc-dc multilevel boost converter which is utilized for generating three voltages at its output terminal. In addition a dc-ac multilevel converter apt for the engendered dc bus voltages generates seven levels at its output terminal. The proposed system has the advantages...
In this experimental study two solar technologies concentration and the flat plate collector were combined in one solar air heater with a Linear Fresnel Reflector (SAHLFR). A rectangular useful duct with 2.32 [m] length and 0.2 [m] width is equipped with and without artificial roughness. This roughness has wrought of steel galvanized 0.4 [mm] thickness to create a turbulent flow of air and ensure...
A powder oxide with composition analogous to the apatite phosphate, was synthesized by dissolution and precipitation of Moroccan natural phosphate, then used as carrier for deposition of different amount of nickel. The support and the resulting catalysts were characterized by several techniques. XRD characterization showed that the support has the crystalline structure typical of apatite oxides. According...
The energy generated using a photovoltaic (PV) are depends mainly on meteorological factors such as temperature and solar radiation. Considering the high cost and the low efficiency of a PV system, it must operate at maximum power point (MPP) which changes with the load variations and weather conditions. This article presents the conception of a nonlinear controller for the DC-DC converter to retrieve...
Successful simple preparation of nanocrystalline SnO2 films was performed by the Sol-Gel spin coating method in an alcoholic medium without any complexing agent. The precursor concentration effect on structural, optical and electrical properties was examined. The X-ray Diffraction (XRD) characterization shows the formation of single tetragonal rutile phase with (110) plan as preferential orientation...
The doubly fed induction generator (DFIG) is the most used technology when it comes to the production of the electric energy for wind power generation. It has the advantage to insure a variable speed operation that will maximize the power extracted from the wind, increase the energy efficiency, reduce the torque oscillations and to generate an electric power with better quality. When we talk about...
Growing concern over the threat of global climate change, and the ineluctable depletion of raw energy resources have led to an increased interest in research and development of renewable energy technologies. The ocean provides a wide potential energy resources, and as renewable energy technology develops, investment in ocean energy is likely to grow. Research in ocean thermal energy conversion, wave...
Under voltage dip conditions, the induced rotor over-currents of the doubly fed induction generators (DFIG) may greatly destroy the converter switches. In this paper, a nonlinear control based on integral backstepping control (IBC) strategy is presented to enhance the Low voltage ride-through (LVRT) of DFIG. The goal of the proposed control strategy applied to rotor side converter (RSC) and grid side...
The diffusion of hydrogen in the rutile and fluorite structures of the magnesium titanium hydrides Mg1−xTixH2 is studied using first-principles density functional theory. We compare the vacancy formation, the diffusion and the binding energy in both structures for x=0.125 and x=0.25 concentrations. Our results confirm that the enhancement of the diffusion is mainly due to the structural change, where...
The scale of a photovoltaics (PVs) field exists between the regional scale and the scale of the air flow on a single PV panel. Field-scaled wind conditions are defined and used in the current study. They are designed after the case of QEERI solar test facility in Doha, Qatar, using a modeling approach based on Computational Fluid Dynamics. The modeling and simulation of such standardized ‘wind’ conditions...
Several numerical models were adopted to simulate the flow behavior inside an oscillating column OWC device. The current paper presents a comparison between two numerical models, the prime is based on the study of the air flow in a simplified OWC piston model, and the other takes into consideration the whole domain composed of the OWC chamber coupled with a wave tank WT; which enable to investigate...
The increasing use of nonlinear loads entails serious electrical energy quality problems in power grids. In this regards, the Three-level shunt active power filter (SAPF) is proposed. The considered SAPF is constituted by an AC/DC Three-level NPC inverter. This latter is connected to the point of common coupling (PCC) through a high order filter instead of conventional filter L. Indeed, a new model...
We investigated the formation of microcrystalline silicon (μc-Si:H) epitaxially grown on the polysilicon seed layer on the aluminium(Al) substrate using Electron cyclotron resonance plasma enhanced chemical vapor deposition method (ECR-PECVD). The μc-Si:H film serves as an active intrinsic absorber layer for a PIN configuration solar cell. A seed polysilicon (P+) layer was created by depositing amorphous...
In the present study, the variation of the band gap energy with biaxial strain in SnO2 in its bulk form is examined using state-of-the-art first-principles calculations. All calculations were based on DFT within the Tran-Blaha modified Becke-Johnson exchange potential approximation (TB-mBJ). Under biaxial compressive and tensile strain, the projected densities of states showed that valence and conduction...
This paper introduces a maximum power point method (MPPT) based on an artificial neural network (ANN) and a scanning algorithm. The proposed MPPT is applied to pumping system. The system is composed of solar generator, boost converter and centrifugal pump load driven by a DC motor. A complete simulation of the system is developed in MATLAB/SIMULINK under different weather conditions. The results obtained...
Density functional theory calculations (DFT), including van der Waals interactions, have been carried out to evaluate the prospects of a novel 2D nanomaterial, phosphorene as a promising anode material for Li-ion batteries. We determined adsorption energies and diffusion barriers on different paths of a single layer phosphorene. Our results showed that at low coverage, Li binds strongly with phosphorene...
The Liquefied Petroleum Gas (LPG) separation unit is one of process, in chemical industries that consume great energy. In this work, Pinch technology for heat recovery is used to minimize the energy consumption of the LPG separation process, for a Moroccan oil refinery. This methodology was applied to the study of the separation of LPG, using the two distillation columns: recovery and splitter columns...
Natural ventilation offers opportunities for reducing cooling energy-demand at low cost for the climate Saharan, and can create a comfortable and healthy indoor environment, and save energy used in the mechanical ventilation systems, have an important role on the balance between heating and cooling needs, It is also necessary to study the possible combinations with natural resources, this natural...
Information and communication technologies have crucial role with many researches improving existing electrical grid. With the emergence of the internet of things and the growing availability of connected devices such as smart meters and other sensors, we are facing huge amount of data about energy consumption, energy production and so on. In this context, smart grid data management and analytics...
This study presents a simulation procedure to describe the current-voltage and power-voltage characteristics of photovoltaic (PV) solar cell or module of different types of technologies; mono-crystalline silicon, multi-crystalline silicon and Thin film under various level of irradiation and different value of temperature based on LabVIEW software. The desired parameters of PV module including short...
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