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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Komplexní provozní diagnostika FVE-T14 - opatření pro optimalizaci provozu / Operational Diagnostics of PV plant -T14 - Operation Optimizing

Kroutil, Roman January 2016 (has links)
The aim of the Thesis is theoretical clarification of the issues of photovoltaic power plants, their diagnostics, inspection and performance measurement, including negative impacts on their operation and subsequent application of theoretical knowledge during practical inspection and diagnostics of PV power plants. In its introductory part, the Thesis deals with design, manufacturing and development of PV cells and panels and describes other necessary elements and components, including their use in individual types of photovoltaic systems. Another part describes electric parameters of PV cells and panels, especially the parameters that can be found out by measurement of V-A characteristics and also the parameters affecting the shape of the V-A characteristics. The third part is focused on failures of photovoltaic systems, which include various defects of photovoltaic cells and panels, it also provides for adverse factors affecting operation of the entire system, associated not only with weather influences but also with the actual design of the photovoltaic system. The fourth part deals with possibilities of increasing the cost-effectiveness of electricity generation by PV power plants on the basis of practical experience of their operators. The subsequent part determines, on the basis of technical standards, procedures for PV power plant inspections, the procedures for measurement and diagnostics of PV power plants and also other prerequisites connected with inspections and measurements. This part includes also a description of requirements for measuring devices, most frequent measurement errors, adverse impacts affecting measurements and methods of assessment of the data measured. The last part of the Thesis is practical. At first it deals with verification of the impact of defects of PV modules on the shape of their V-A characteristics, then with execution of inspections and diagnostics of a particular PV power plant, evaluation of the data identified and measured, as well as with a proposal of optimisation measures to increase cost-efficiency of the operation of that particular PV power plant.
92

Environmentálně vyspělá budova - pro sportovní aktivity / Environmentally advanced building - for sports activities

Krahula, Tomáš January 2022 (has links)
The task of the master project is to design a building for sports activities in Sehradice, Zlín region. First the documentation was elaborated, the second part HVAC was designed and the last part focussed on daylighting. The building has one floor and flat green roof. The building includes a fitness, a yoga room, a relax room, two saunas, changing rooms and staff room. The superstructure is designed using Heluz ceramic block walls and Spiroll panel floor structure. Façade is insulated with ETICS. HVAC is provided by two gas boilers, two mechanical ventilation units (indoors) and a cooling unit (outdoor). Domestic hot water is provided by the gas boiler and solar panels. The building uses LED lights. Electricity consumption is partially covered by photovoltaics on the roof. The building plot also includes a large carpark in front of the building. The designs were elaborated in Revit, AutoCAD and energy assessment in Deksoft software.
93

蓄電池併設型太陽光発電用パワーコンディショナを活用したエネルギーマネジメントシステムに関する研究 / チクデンチ ヘイセツガタ タイヨウコウ ハツデンヨウ パワー コンディショナ オ カツヨウ シタ エネルギー マネジメント システム ニカンスル ケンキュウ

遠藤 浩輝, Hiroaki Endo 22 March 2020 (has links)
本論文では,電力利用率向上と需給バランス調整に寄与する蓄電池付太陽光PCSの新たな制御法について検討を行い,その有効性を確認している。受電点の潮流に応じてPCSの力率を制御することで,逆潮流時には系統電圧の上昇を抑制しつつ,順潮流時には負荷への電力利用率を向上する手法を提案し,フィールド試験により有効性を定量評価した。また,受電電力の制御目標値を可変とする制御を用い目標値を最適化することで,新たな機器を付加する必要なく上げ下げのDRに対応し需給バランスを調整する制御手法を提案し,その有効性をシミュレーションおよび実機により検証した。 / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University
94

Monteringshöjd och markinterferens i nordliga solkraftsparker : Minskade skuggningseffekter från ansamling av snö i markmonterade solcellsanläggningar i norra Sverige.

Edebo, Gabriella January 2023 (has links)
Markmonterade solcellsanläggningar i norra Sverige behöver ta hänsyn till förekomsten av snö och risken för markinterferens, vilket innebär att snömängden i framkant av panelerna gör att den snö som ackumuleras ovanpå inte kan glida av. Följden blir skuggning av panelerna som därmed får nedsatt eller helt utebliven elproduktion. Syftet med arbetet var att besvara frågeställningar kring vilken montagehöjd som krävs för att undvika problemet samt om den ökade engångskostnaden kompenseras av potentialen till ökad produktion under vintermånaderna. Metoden bestod främst av att jämföra produktionsdata från en solpark i Östersund med värden för solinstrålning och snödjup från SMHI för att avgöra vilken effekt snöskuggning haft på produktionen och hur utfallet skulle ha sett ut vid olika monteringshöjder av anläggningen. Resultaten visar att det finns stor potential till goda produktionsvärden under vårvintern, förutsatt att markinterferens inte finns närvarande. Anledningen beror troligtvis på högt albedo från snötäckt mark och lägre lufttemperaturer vilket har en positiv inverkan på modulernas verkningsgrad. En beräkningsmodell utvecklades för att uppskatta en lämplig monteringshöjd för en solpark utifrån dess tänkta utformning och det förväntade snödjupet på platsen. Förhoppningen är att modellen kan bidra till ökad kunskap för att främja utbyggnad av markmonterade solcellsanläggningar även på nordliga breddgrader. Lönsamheten för ett högre montage undersöktes genom en jämförelse mellan ett prisexempel från en uppförd solpark och ett uppskattat produktionsbortfall från solparken i Östersund vid en teoretiskt lägre monteringshöjd. Det visade att en höjning av Östersundsparken från 50 till 90 centimeter skulle betala av sig enbart genom tillskottet i produktion under perioden februari till april de tre första vintrarna. / Ground-mounted PV installations in northern Sweden need to consider the presence of snow and the risk of ground interference, meaning that the buildup of snow in front of the panels prevents the snow accumulated on top from sliding off. The result is shading of the panels, which in turn reduces or eliminates the electricity production. The purpose of this work was to answer questions regarding the mounting height required to avoid this problem and whether the increased one-time cost for higher mounting is compensated for by the enhanced production during winter months. The method consisted mainly of comparing production data from a solar park in Östersund to solar radiation values and snow depth from SMHI to determine the effect of snow shading on production and the outcome at different installation heights of the plant. The results showed that there is great potential for valuable energy production during the late winter season, provided that ground interference is not present. This is probably due to high albedo from snow-covered ground and lower air temperatures resulting in a positive impact on the efficiency of the modules. A computational model was developed to estimate a suitable mounting height for a solar park based on the intended design and expected snow depth at the site. The intention is that the model can contribute to increased knowledge to promote the deployment of ground-mounted PV systems in northern latitudes. The profitability of higher mounting was investigated by comparing a price example from an existing solar facility and an estimated production loss from the solar park in Östersund at a theoretical lower mounting height. It showed that  increasing the height of the Östersund site from 50 to 90 centimeters in front would pay off solely on the enhanced production during the period February to April of the first three winters.
95

[en] RESIDENTIAL PHOTOVOLTAIC SYSTEMS IN BRAZIL: A TECHNICAL-ECONOMIC ANALYSIS FROM THE PERSPECTIVE OF PROSUMERS AND UTILITIES / [pt] SISTEMAS FOTOVOLTAICOS RESIDENCIAIS NO BRASIL: UMA ANÁLISE TÉCNICO-ECONÔMICA SOB A PERSPECTIVA DE PROSUMIDORES E DISTRIBUIDORAS

30 December 2021 (has links)
[pt] As mudanças recentes nas matrizes elétricas mundiais são geralmente motivadas pela busca de fontes de energia mais limpas e pela dificuldade na construção de novas gerações centralizadas. Como resultado, este estímulo altera não apenas a tecnologia da fonte de energia, mas também a sua localização, que agora passa a ser mais próximas aos centros consumidores ou até mesmo conectadas à rede de distribuição, como a Geração Distribuída (GD). No Brasil, a GD possui um arcabouço regulatório que permite aos seus adeptos, chamados de prosumidores, terem um papel ativo na rede de distribuição, injetando e consumindo eletricidade consoante o seu balanço elétrico. Esse comportamento traz novos desafios para as companhias de distribuição, e, embora alguns benefícios da GD possam ser obtidos para essas companhias, a perda de mercado e diminuição de suas receitas fixas podem acarretar em transferência de custos estruturais, dos prosumidores para os consumidores sem este tipo de instalação. Nesse contexto, o presente trabalho realiza uma análise técnico-econômico, para novos empreendimentos residenciais de GD fotovoltaica, parcela mais significativa de GD no Brasil. Essa análise considera todas as opções propostas de revisão da regulação de GD pelo órgão regulador e aborda tanto o impacto no retorno do investimento pelos prosumidores, quanto o impacto nas receitas em todas as distribuidoras do país. Para isto, no âmbito do investidor, serão avaliados três diferentes fatores econômicos: LCOE, payback descontado e benefício-custo; já no âmbito da distribuidora, será avaliado o impacto do aumento das GD na receita da empresa e na tarifa de energia elétrica imposta pela mesma, para tanto será realizado uma previsão de mercado para os próximos dez anos, considerando o modelo baseado em Bass. Os estudos realizados apontaram que qualquer uma das opções propostas pelo órgão regulador causará uma redução do mercado aderente a instalação da GD, o que consequentemente levará a uma redução dos prejuízos das distribuidoras e cenários menos favoráveis ao investimento pelo lado do prosumidor. / [en] Recent changes in the world s electrical mix are generally motivated by the search for cleaner energy sources and by the difficulty in building new centralized power plants. As a result, this stimulus changes not only the energy source technology, but also its location, which is now closer to consumer centers or even connected to the distribution network, such as Distributed Generation (DG). In Brazil, DG has a regulatory framework that allows its supporters, called prosumers, to play an active role in the distribution network, injecting and consuming electricity according to their own electrical balance. This behavior brings new challenges for distribution companies, and although some benefits of DG can be obtained for these companies, the loss of market and reduction of their fixed revenues can result in the transfer of structural costs, from prosumers to consumers without this type of installation. In this context, this work performs a technical-economic analysis for new residential projects of photovoltaic DG, the most significant portion of DG in Brazil. This analysis considers all proposed options for reviewing DG regulation by the regulatory body and addresses both the impact on return on investment by prosumers and the impact on revenues in all distribution companies in the country. For this, within the investor, three different economic factors are evaluated: LCOE, discounted payback and benefit-cost; within the scope of the distribution companies, the impact of the increase in DG on the company s revenue and on their electricity tariff are also evaluated, for which a market forecast will be made for the next ten years, considering the model based on Bass. The obtained results indicate that any of the options proposed by the regulatory agency will cause a reduction in the market adherent to the installation of the DG, which will consequently lead to a reduction in the revenue losses for distribution companies and less favorable scenarios for investment on the prosumer side.
96

[en] PHOTOVOLTAIC SYSTEMS CONNECTED TO THE ELECTRICITY GRID IN LOW-INCOME COMMUNITIES AS AN INSTRUMENT OF SOCIAL TECHNOLOGY AND FOR THE ENERGY TRANSITION / [pt] SISTEMAS FOTOVOLTAICOS CONECTADOS À REDE EM COMUNIDADES DE BAIXA RENDA COMO INSTRUMENTO DE TECNOLOGIA SOCIAL E PARA TRANSIÇÃO ENERGÉTICA

DIOGO COUTO LAGE 19 February 2024 (has links)
[pt] Esta pesquisa investiga as possibilidades de utilização de sistemas fotovoltaicos conectados à rede (SFCR) em comunidades de baixa renda, com o objetivo de compreender como esses sistemas podem ser empregados como ferramentas para promover a inclusão social. O objetivo geral da pesquisa é analisar o uso de SFCR em comunidades de baixa renda no Brasil, buscando entender como esses sistemas podem promover a inclusão social e impulsionar a transição energética justa. Além disso, este estudo explora a conexão entre o uso de SFCR e o conceito de tecnologia social. Para enriquecer e aprofundar a pesquisa, adotou-se o método de pesquisa bibliográfica e análise documental com abordagem qualitativa. Conduziu-se uma extensa busca em diferentes bases de dados, como o SciELO, plataforma Capes e Google Acadêmico, com o objetivo de localizar materiais pertinentes e atualizados para embasar o estudo de forma consistente e abrangente. Os projetos selecionados para a análise documental foram a REVOLUSOLAR e SOLAR PILAR, ambas situadas no Rio de Janeiro. Foram coletados dados documentais e informações oficiais fornecidas pelos projetos, com o intuito de compreender suas estruturas, operações e abordagens de implementação. A análise foi conduzida em consonância com a Matriz de Avaliação Multidimensional, permitindo identificar como esses projetos estavam alinhados com os conceitos estudados. Assim, por meio da análise documental, foi possível investigar como esses projetos incorporaram os princípios de tecnologia social, economia social, transição energética justa e autogestão comunitária, contribuindo para uma compreensão mais aprofundada da aplicação prática desses conceitos em contextos reais. Portanto, o uso do SFCR em processos interativos com a participação das comunidades para solucionar problemas locais foi uma estratégia versátil, adaptada a diferentes projetos. No Brasil, as políticas públicas nacionais, tradicionalmente focadas em educação, saúde, complemento de renda e habitação, visaram atender urgências e obter reconhecimento político. Entretanto, projetos relacionados a matrizes renováveis permaneceram considerados alternativos, geralmente experimentais e localizados, com crescimento lento devido ao seu impacto limitado. A análise de dois projetos existentes evidenciou que, apesar de incentivos sociais e tarifários, o Brasil ainda carecia de políticas públicas para uma transição energética justa, demandando maior atenção a abordagens como as apresentadas na pesquisa. O Programa de Energia Renovável Social (PERS) destaca-se como uma oportunidade para avanços significativos no uso de SFCR em comunidades de baixa renda, promovendo inclusão social na transição energética. Para o sucesso do PERS, é fundamental que as políticas públicas se concentrassem nas comunidades mais carentes, promovendo autogestão e empreendedorismo comunitário, com a formação de cooperativas de energia renovável e o fornecimento de treinamento para gestão autônoma dos sistemas de energia renovável. / [en] This research investigates the possibilities of using grid-connected photovoltaic systems (SFCR) in low-income communities, aiming to comprehend how these systems can be employed as tools to promote social inclusion. The overall objective of the research is to analyze the use of SFCR in low-income communities in Brazil, seeking to understand how these systems can foster social inclusion and drive a fair energy transition. Additionally, this study explores the connection between the use of SFCR and the concept of social technology. To enrich and deepen the research, the methodology of bibliographic research and documentary analysis with a qualitative approach was adopted. An extensive search was conducted across different databases such as SciELO, Capes platform, and Google Scholar, with the aim of locating relevant and updated materials to support the study consistently and comprehensively. The selected companies for documentary analysis were REVOLUSOLAR and SOLAR PILAR, both located in Rio de Janeiro. Documentary data and official information provided by the projects were collected to understand their structures, operations, and implementation approaches. The analysis was carried out in accordance with the Multidimensional Evaluation Matrix, allowing the identification of how these projects aligned with the studied concepts. Through documentary analysis, it was possible to investigate how these projects incorporated the principles of social technology, social economy, fair energy transition, and community self-management, contributing to a deeper understanding of the practical application of these concepts in real contexts. Therefore, the use of SFCR in interactive processes involving community participation to solve local issues proved to be a versatile strategy, adaptable to different projects. In Brazil, national public policies, traditionally focused on education, health, income supplementation, and housing, aimed to address urgencies and gain political recognition. However, projects related to renewable matrices remained considered alternative, often experimental and localized, with slow growth due to their limited impact. The analysis of two existing projects revealed that, despite social and tariff incentives, Brazil still lacked public policies for a fair energy transition, requiring greater attention to approaches presented in the research. The Renewable Social Energy Program (PERS) stood out as an opportunity for significant advancements in the use of SFCR in low-income communities, promoting social inclusion in the energy transition. For the success of PERS, it was crucial for public policies to focus on the most vulnerable communities, promoting community self-management and entrepreneurship through the formation of renewable energy cooperatives and providing training for the autonomous management of renewable energy systems.
97

Machine learning based user activity prediction for smart homes

Goutham, Mithun January 2020 (has links)
No description available.
98

Corrente de fuga em inversores monofásicos sem transformador para conexão de sistemas fotovoltaicos à rede de distribuição de energia elétrica: análise e proposta de filtro passivo integrado de modo comum e diferencial. / Leakage current in single-phase transformerless inverters for the connection of photovoltaic systems to the distribution grid: analysis and proposal of an integrates common and differential mode passive filter.

Ricardo Souza Figueredo 21 May 2015 (has links)
Este trabalho apresenta um estudo sobre a corrente de fuga de modo comum em inversores monofásicos sem transformador utilizados para a conexão de sistemas fotovoltaicos (FV) à rede de distribuição de energia elétrica. O estudo se concentra em inversores do tipo fonte de tensão que empregam a topologia em ponte completa. A partir da adequada modelagem do sistema (rede, conversor e módulo fotovoltaico) identifica-se e quantifica-se a contribuição das tensões de modo comum e modo diferencial para a corrente de fuga. Conclui-se que a tensão de modo comum de alta frequência produzida pelo inversor, que depende da estratégia de modulação por largura de pulso (PWM Pulse Width Modulation) empregada, fornece a maior contribuição para produção da corrente de fuga. Esse estudo mostra que os inversores sem transformador, com topologia em ponte completa e modulação que produz tensão de saída com três níveis, necessitam de medidas adicionais para a minimização da corrente fuga quando aplicados em sistemas fotovoltaicos conectados à rede. Algumas soluções propostas na literatura para a minimização da corrente de fuga baseadas em topologias modificadas e filtros de modo comum são listadas e discutidas. Neste trabalho é proposto um filtro integrado de modo comum e modo diferencial com amortecimento passivo de baixas perdas, para minimizar a corrente de fuga produzida por um inversor monofásico sem transformador. Um exemplo de aplicação do filtro proposto é apresentado juntamente com seu procedimento de projeto, resultados de simulação e experimentais que validam a proposta. Além disso, a influência da variação da indutância da rede elétrica e da capacitância parasita do sistema fotovoltaico no comportamento do filtro proposto é analisada. A influência da variação da indutância da rede no comportamento do sistema de controle e o impacto da corrente de modo comum no projeto dos indutores do lado do conversor também são analisados. / This paper presents a study on the common mode leakage current in single-phase transformerless inverters for grid-connected photovoltaic (PV) systems. The study focuses on voltage source inverters (VSI) employing the full-bridge topology. The common mode and differential mode voltages that contribute to the leakage current are identified and quantified from the analysis of the system model (utility grid, converter and PV module). The system model analysis shows that the high frequency common mode voltage produced by the inverter, which depends on the Pulse Width Modulation (PWM) strategy, is the main source contributing to the leakage current. This work shows that transformerless inverters employing the full-bridge topology and a modulation strategy that produces a three-level output voltage require some leakage current minimization strategy when they are employed in grid-connected PV systems. Some solutions proposed in the literature for leakage current minimization based on modified topologies and common mode filters are listed and discussed. In this dissertation an integrated common and differential filter with low loss passive damping is proposed to minimize the leakage current produced by a single-phase transformerless PV inverter. An application example of the proposed filter is presented with design procedure, simulation and experimental results validating the proposal. Additionally, the influence of grid inductance and PV module parasitic capacitance variations on the behavior of the proposed filter is analyzed. The behavior of the control system considering the grid inductance variation and the impact of the common mode current on the converter side inductors design are also analyzed.
99

Corrente de fuga em inversores monofásicos sem transformador para conexão de sistemas fotovoltaicos à rede de distribuição de energia elétrica: análise e proposta de filtro passivo integrado de modo comum e diferencial. / Leakage current in single-phase transformerless inverters for the connection of photovoltaic systems to the distribution grid: analysis and proposal of an integrates common and differential mode passive filter.

Figueredo, Ricardo Souza 21 May 2015 (has links)
Este trabalho apresenta um estudo sobre a corrente de fuga de modo comum em inversores monofásicos sem transformador utilizados para a conexão de sistemas fotovoltaicos (FV) à rede de distribuição de energia elétrica. O estudo se concentra em inversores do tipo fonte de tensão que empregam a topologia em ponte completa. A partir da adequada modelagem do sistema (rede, conversor e módulo fotovoltaico) identifica-se e quantifica-se a contribuição das tensões de modo comum e modo diferencial para a corrente de fuga. Conclui-se que a tensão de modo comum de alta frequência produzida pelo inversor, que depende da estratégia de modulação por largura de pulso (PWM Pulse Width Modulation) empregada, fornece a maior contribuição para produção da corrente de fuga. Esse estudo mostra que os inversores sem transformador, com topologia em ponte completa e modulação que produz tensão de saída com três níveis, necessitam de medidas adicionais para a minimização da corrente fuga quando aplicados em sistemas fotovoltaicos conectados à rede. Algumas soluções propostas na literatura para a minimização da corrente de fuga baseadas em topologias modificadas e filtros de modo comum são listadas e discutidas. Neste trabalho é proposto um filtro integrado de modo comum e modo diferencial com amortecimento passivo de baixas perdas, para minimizar a corrente de fuga produzida por um inversor monofásico sem transformador. Um exemplo de aplicação do filtro proposto é apresentado juntamente com seu procedimento de projeto, resultados de simulação e experimentais que validam a proposta. Além disso, a influência da variação da indutância da rede elétrica e da capacitância parasita do sistema fotovoltaico no comportamento do filtro proposto é analisada. A influência da variação da indutância da rede no comportamento do sistema de controle e o impacto da corrente de modo comum no projeto dos indutores do lado do conversor também são analisados. / This paper presents a study on the common mode leakage current in single-phase transformerless inverters for grid-connected photovoltaic (PV) systems. The study focuses on voltage source inverters (VSI) employing the full-bridge topology. The common mode and differential mode voltages that contribute to the leakage current are identified and quantified from the analysis of the system model (utility grid, converter and PV module). The system model analysis shows that the high frequency common mode voltage produced by the inverter, which depends on the Pulse Width Modulation (PWM) strategy, is the main source contributing to the leakage current. This work shows that transformerless inverters employing the full-bridge topology and a modulation strategy that produces a three-level output voltage require some leakage current minimization strategy when they are employed in grid-connected PV systems. Some solutions proposed in the literature for leakage current minimization based on modified topologies and common mode filters are listed and discussed. In this dissertation an integrated common and differential filter with low loss passive damping is proposed to minimize the leakage current produced by a single-phase transformerless PV inverter. An application example of the proposed filter is presented with design procedure, simulation and experimental results validating the proposal. Additionally, the influence of grid inductance and PV module parasitic capacitance variations on the behavior of the proposed filter is analyzed. The behavior of the control system considering the grid inductance variation and the impact of the common mode current on the converter side inductors design are also analyzed.
100

Modélisation de solides à nanocristaux de silicium / Modelling of silicon nanocrystal solids

Lepage, Hadrien 22 October 2012 (has links)
Les propriétés physico-chimiques d'un nanocristal semi-conducteur sphérique, intermédiaires entre la molécule et le solide, dépendent de sa taille. Empilés ou dispersés, ces nanocristaux sont les briques architecturales de nouveaux matériaux fonctionnels aux propriétés ajustables, en particulier pour l’optoélectronique. Cette thèse s'inscrit dans le développement de ces nouveaux matériaux et présente avant tout une méthodologie pour la simulation du transport électronique dans un solide à nanocristaux en régime de faible couplage électronique appliquée à des nanocristaux de silicium dans une matrice de SiO2 pour les applications photovoltaïques. La cinétique du déplacement des porteurs est liée au taux de transfert tunnel (hopping) entre nanocristaux. Ces taux sont calculés dans le cadre de la théorie de Marcus et prennent en compte l'interaction électron-phonon dont l'effet du champ de polarisation dans la matrice ainsi que les interactions électrostatiques à courte et longue portée. Le calcul des états électroniques (électrons et trous) en théorie k.p associé à l'utilisation de la formule de Bardeen donne au code la capacité, par rapport à la littérature, de fournir des résultats (mobilité ou courant) en valeur absolue. Les résultats de mobilité ainsi obtenus pour des empilements cubiques idéaux viennent contredire les résultats de la littérature et incitent à considérer d'autres matériaux notamment en ce qui concerne la matrice pour obtenir de meilleurs performances. En outre, les résultats de simulation de dispositifs montrent l'impact considérable des électrodes sur les caractéristiques courant-tension. Aussi, un nouvel algorithme Monte-Carlo Cinétique accéléré a été adapté afin de pouvoir reproduire le désordre inhérent à la méthode de fabrication tout en maintenant un temps de simulation raisonnable. Ainsi l'impact du désordre en taille se révèle faible à température ambiante tandis que les chemins de percolation occultent la contribution des autres chemins de conduction. Des résultats de caractérisation comparés aux simulations tendent par ailleurs à indiquer que ces chemins peuvent concentrer les porteurs et exhiber un phénomène de blocage de coulomb. Enfin, la section efficace d'absorption est calculée théoriquement et permet d'obtenir le taux de génération sous illumination qui se révèle proche du silicium massif. Et une méthode en microscopie à sonde de Kelvin est décrite pour caractériser la durée de vie des porteurs c'est-à-dire le taux de recombinaison, les résultats ainsi obtenus étant cohérents avec d'autres techniques expérimentales. / The physicochemical properties of a spherical semiconductor nanocrystal, intermediate between the molecule and the solid depend on its size. Stacked or dispersed, these nanocrystals are building blocks of new functional materials with tunable properties, particularly appealing for optoelectronics. This thesis takes part in the development of these new materials. It mainly presents a methodology for the simulation of electronic transport in nanocrystal solids within the weak electronic coupling regime. It is applied to a material made of silicon nanocrystals embedded in silicon oxide and considered for photovoltaïc applications. The displacement kinetics of charge carriers is related to the tunneling transfer rate (hopping) between nanocrystals. These rates are calculated within the framework of Marcus theory and take into account the electron-phonon interactions, the effect of the bias field and the electron-electron interactions at short and long range. The calculation of electronic states (electrons and holes) in k.p theory associated with the use of Bardeen's formula provides, compared to previous works, results (mobility or current) in absolute terms. The mobility thus computed is far lower than the results of the literature and encourage to consider other materials. Furthermore, the device simulations show the significant impact of the electrodes on the current-voltage characteristics. Also, a new accelerated kinetic Monte-Carlo algorithm has been adapted in order to reproduce the disorder inherent in the manufacturing process while maintaining a reasonable simulation time. Thus the impact of the size disorder is poor at room temperature while the percolation paths shunt the contribution of other conduction paths. Characterization results compared to simulations tend to show that these paths concentrate carriers and exhibit Coulomb blockade phenomenon. Finally, the absorption cross section is calculated theoretically to obtain the generation rate under illumination. It is similar to the bulk silicon one. And a method employing a Kelvin probe microscope is described to characterize the carrier lifetime, namely the recombination rate. The results thus obtained are consistent with other experimental technics.

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