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Performance Study of a Quadratic Boost Converter

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Circuits and Systems 2024年第2期15卷 13-27页

作者： Modou Badiane Prince Abdoul Aziz Honadia Oumar Diallo Sadio fabé Idrissa Barro Department of Physics Semiconductors and Solar Energy Laboratory Faculty of Science and Technique Cheikh Anta Diop University Dakar Senegal Renewable Thermal Energy Laboratory Kaya University Centre Ouagadougou Burkina Faso

Energy is the driving force behind all economic and industrial development. Africa is the least advanced continent in terms of energy consumption and production. Paradoxically, it is the sunniest continent, which is why our objective is to exploit this energy potential in order to produce and use sufficient energy. To achieve this, we are carrying out a series of studies aimed at developing a device capable of converting solar photovoltaic energy into electrical energy. This device is a two-stage converter, the first of which is a quadratic boost and the second a full bridge. Initially, this paper is devoted to studying the performance of the quadratic boost.

关键词： Solar Energy Photovoltaic Efficiency Quadratic Boost Converter

Investigation of grain mass flow in a mixed flow dryer

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Particuology 2014年第1期12卷 33-39页

作者： fab.an weigler Jochen Mellmann Department of Post-harvest Technology Leibniz Institute for Agricultural Engineering Potsdam-Bornim

The numerical modeling of grain drying is a topic of great relevance to post-harvest engineering. The required type of drying process depends on the quantity of grain to be dried and the required quality of the grain. The choice of the drying system depends on the operating parameters of the drying process. The granular flow pattern of the material exerts a significant influence on the drying process. Post-harvest drying of grain is essential for better storage, handling, and processing. Therefore, it is important to know the material behavior that controls the particle flow patterns of grain in the drying equipment to guarantee the product quality and to optimize the drying process conditions. The discrete element method （DEM） was applied to investigate the particle flow pattern of wheat through a mixed-flow dryer （MFD） without airflow, and the findings were compared with experimental results in this work. The investigations were performed using dry wheat with 14 wb% moisture content.

关键词： Keywords:Mixed-flow dryerGrain mass flowDiscrete element method

Influence of the number of flights on the dilute phase ratio in flighted rotating drums by PTV measurements and DEM simulations

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Particuology 2021年第3期19卷 171-182页

作者： Lanyue Zhang Zhaochen Jiang Jochen Mellmann fab.an weigler fab.an Herz Andreas Bück Evangelos Tsotsas Department of Postharvest Technology Leibniz Institute for Agricultural Engineering and BioeconomyMax-Eyth-Allee 100Potsdam 14469Germany Thermal Process Engineering Otto von Guericke University MagdeburgUniversitaetsplatz 239106 MagdeburgGermany Institute of Particle Technology(LFG) FAU Erlangen-NurembergCauerstr.491058 ErlangenGermany Department of Applied Biosciences and Process Engineering Anhalt University of Applied SciencesBernburgerStr.5506366 KoethenGermany

Particle distribution in the cross-section of the flighted rotating drum(FRD)is critical to the analysis of heat and mass transfer between gas and *** this work,the particle tracking velocimetry(PTV)method is applied to study the influence of the number of flights on the particle motion in *** drum,installed with 1,4,8,or 12 rectangular flights,is filled with plastic balls to 15%and operated at various rotating speeds ranging from 10 rpm to 30 *** results show that the number of flights has different effects on the holdup ratio and cascading rate of single flight and active *** 8 and 12 flights,the FRD produces a larger and more stable particle ratio of the dilute ***,DEM simulations agree with PTV measurements,whereas literature models show significant deviations.

关键词： Flighted rotating drum Number of flights Dilute phase PTV DEM

Soil attributes structure plant assemblages across an Atlantic forest mosaic

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Journal of Plant Ecology 2018年第4期11卷 613-622页

作者： Maria fabíola Barros Bruno X.Pinho Tarciso Leão Marcelo Tabarelli Programa de Pós-Graduação em Biologia Vegetal Departamento de BotânicaUniversidade Federal de PernambucoPE 50670-901Brazil Department of Forest Resources University of MinnesotaSt.PaulMN 55108USA

Aims Community assembly persists as a key topic in ecology due to the complex variation in the relative importance of assembly forces and mechanisms across spatio-temporal scales and *** we address a forest-savanna vegetation mosaic in the Brazilian Atlantic forest to examine the role played by soil attributes as determinants of community assembly and organiza-tion at a landscape spatial *** We examined soil and plant assemblage attributes across 23 plots of forest and savanna in a 1600 km2 landscape exposed to the same climatic conditions in the Atlantic forest region of northeast *** attributes included species richness,taxonomic and functional composition(community weighted mean,CWM)and functional diversity(quadratic diversity;Rao’s quadratic entropy index)relative to plant leaf area,specific leaf area,leaf dry matter content,thickness and *** Findings Our results suggest that forest and savanna patches exposed to the same climatic conditions clearly differ in terms of soil attributes,plant assemblage structure,taxonomic and functional *** selecting particular plant strategies relative to resource economy,soil potentially affects community structure,with forest assemblages bear-ing more acquisitive resource-use strategies,while conservative plant strategies are more frequent in ***,savanna-forest mosaics in the Atlantic forest region represent spatially organized plant assemblages in terms of taxonomic and functional features,with a sig-nal of trait convergence in both vegetation ***-mediated filter-ing thus emerges as a potential deterministic assembly force affecting the spatial organization of savanna-forest boundaries and mosaics.

关键词： community assembly habitat filtering plant functional traits savanna vegetation tropical forest

Microbiological biostimulant promotes rooting of olive cuttings

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International Journal of Agricultural and Biological Engineering 2021年第6期14卷 207-212页

作者： Giovana Ritter fabíola Villa Daniel Fernandes da Silva Odair Alberton Fernanda Jaqueline Menegusso Tatiane Eberling Joyce Dória Western ParanáState University(Unioeste) Campus Marechal Cândido Rondon.Marechal Cândido RondonPR85960-000Brazil Paranaense University(UNIPAR) UmuaramaPR87502-210Brazil Federal University of Lavras LavrasMG37200-000Brazil

The most widely used method of olive propagation is cutting,although for some cultivars the technique is still *** objective of this work was to evaluate the use of plant growth promoter bacteria and arbuscular mycorrhizal fungi in the rooting of olive *** experiments were conducted from October 2017 to January 2018 with cuttings from 4 olive cultivars(Ascolano 315,Koroneiki,Maria da Féand Picual)from four-year-old *** first experiment consisted of 4 olive cultivars and 3 mycorrhizal species plus the control and the second experiment of 3 concentrations of commercial inoculant(Nitro1000®),containing Azospirillum brasilense plus *** cuttings were treated with 3000 mg/L of indolebutyric acid(IBA).The experimental design used in the two experiments was randomized blocks,in a 4×4 factorial scheme,containing 25 stakes per replicate and 3 *** cuttings were kept under weaver conditions and within a low rooting *** 75 d,the percentage of rooted cuttings,callus and sprouts,length of the largest root,number and length of shoots were *** use of FMA in Maria da Féand Picual has a positive response to cutting rooting and the fungi benefit the quality of the seedlings by the higher number of shoots and larger root *** relation of Azospirillum brasilense cultivar is specific,being that,the cultivar Picual does not respond to inoculation of the bacterium having less viability in the propagation by *** da Féand Koroneiki have the best percentages of rooting with the use of 75.00 and 52.00 mL/L of inoculant,respectively.

关键词： Azospirillum brasilense Arbuscular mycorrhizal fungi Propagation Olea europaea L. microorganism

Silicon Solar Cell Space Charge Region and Capacitance Behavior under Electric Field

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Energy and Power Engineering 2021年第1期13卷 41-50页

作者： Bernard Zouma fabé Idrissa Barro Prince Abdoul Aziz Honadia Department of Physics Thermal Renewable Energies Laboratory Training and Research Unit in Exact and Applied Sciences Joseph Ki-Zerbo University Ouagadougou Burkina Faso Department of Physics Semiconductors and Solar Energy Laboratory Faculty of Science and Technique Cheikh Anta Diop University Dakar Senegal

This paper investigates theoretically the behavior of the space charge region of a silicon solar cell and its associated capacitance under the effect of an external electric field. The purpose of this work is to show that under illumination the solar cell’s space charge region width varies with both operating point and the external induced electric field and how the solar cell capacitance varies with the space charge region width. Based on a 1D modelling of the quasi-neutral p-base, the space charge region width is determined and the associated capacitance is calculated taking into account the external electric field and the junction dynamic velocity. Based on the above calculations and simulations conducted with Mathcad, we confirmed the linear dependence of the inverse capacitance with space charge region width for thin space charge region and we exhibit an exponential dependence for large space charge region.

关键词： Solar Cell Electric Field Space Charge Region Capacitance

Performance Analysis of a Boost Converter with Components Losses

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Energy and Power Engineering 2018年第9期10卷 399-413页

作者： Prince Abdoul Aziz Honadia fabé Idrissa Barro Moustapha Sané Department of Physics Semiconductors and Solar Energy Laboratory Faculty of Science and Technique Cheikh Anta Diop University Dakar Senegal

A theoretical study of a conventional boost converter is presented. Based on the real behavior of the components, two models of the boost converter are introduced: one dealing only with losses through inductor and capacitor and another taking into account switching losses in addition to resistive ones. From these two models, the detailed analytical expressions of both voltage gain factor and conversion efficiency are established taking into account the losses through parasitic resistances and switching losses. The behavior of the converter is then analyzed for each model by simulation for the voltage gain factor and the conversion efficiency.

关键词： Boost Gain Factor Efficiency ESR

Quadratic Boost Converter: An Analysis with Passive Components Losses

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Open Journal of Applied Sciences 2021年第2期11卷 202-215页

作者： Modou Badiane Prince Abdoul Aziz Honadia Bernard Zouma fabé Idrissa Barro Department of Physics Semiconductors and Solar Energy Laboratory Faculty of Science and Technique Cheikh Anta Diop University Dakar Senegal Department of Physics Thermal Renewable Energies Laboratory Training and Research Unit in Exact and Applied Sciences Joseph Ki-Zerbo University Ouagadougou Burkina Faso

The Cascaded Connected Single Switch Quadratic Boost (C2S2-QB) is studied first from its ideal model, then with semi-real model taking into account resistive losses through the inductors and the capacitor. The continuous conduction mode equations, describing these different models are established, taking into account losses through passive components. From these equations, the voltage gain and the efficiency are determined for the semi-real model. The voltage gain and the efficiency are then analyzed versus duty cycle and the influence of passive component losses on the performance of the quadratic boost converter is carried out for the semi-real model. It has been showed that the quality of the passive components of a converter plays an important role in the quality of the conversion. However, not all passives components affect the converter in the same way.

关键词： Quadratic Boost Losses Gain Factor Efficiency

Determination of the Electrical Parameters of a Solar Cell in Steady State

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Open Journal of Applied Sciences 2023年第10期13卷 1834-1843页

作者： Omar Diallo Sadio Mamadou Kouyaté Papa Touty Traoré fabé Idrissa Barro Department of Physics Semiconductors and Solar Energy Laboratory Faculty of Science and Technique Cheikh Anta Diop University Dakar Senegal

Photovoltaic solar energy can be obtained by using several types of technologies, including silicon solar cells. The characterization of its solar cells makes it possible to know them better. This article presents, on the one hand, the work that has been carried out on these cells. On the other hand, a theoretical study of the cell under illumination using Lambert’s W function. On the basis of the electrical parameters provided by the manufacturer, the parameters such as the series and shunt resistances and the electrical quantities such as the photocurrent and the photovoltage, are determined and studied according to the ideality factor of the diode. From the results obtained the shunt resistance increases when the ideality factor increases, the series resistance decreases very weakly.

关键词： Solar Cell Series Resistance Shunt Resistance Ideality Factor Lambert Function