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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.
561

Ετήσια ενεργειακή απόδοση πλαισίων λεπτού φιλμ και ισοδύναμη μοντελοποίηση

Τσόλκας, Γεώργιος 16 June 2011 (has links)
Σκοπός αυτής της διπλωματικής εργασίας είναι να εμβαθύνουμε στη λειτουργία των φωτοβολταϊκών πλαισίων λεπτού φίλμ (και συγκεκριμένα των πλαισίων άμορφου πυριτίου - a-Si - και CIS) και μέσα από τα αριθμητικά δεδομένα, να αποφανθούμε πώς η λειτουργία σε πραγματικές συνθήκες μπορεί να επηρεάσει την παραγόμενη ισχύ τους. Στα πλαίσια αυτά, πραγματοποιήθηκαν πειραματικές μετρήσεις, στο χώρο της ταράτσας του κτιρίου του τμήματος των Ηλεκτρολόγων Μηχανικών και Τεχνολογίας Υπολογιστών, με φωτοβολταϊκά πλαίσια άμορφου πυριτίου και CIS ισχύος αιχμής 32 και 75 W αντίστοιχα. Οι μετρήσεις πραγματοποιούνταν μια φορά την εβδομάδα κατά τη διάρκεια ενός ημερολογιακού έτους (Μάιος 2009-Απρίλιος 2010) υπό διάφορες συνθήκες ακτινοβολίας και θερμοκρασίας και για αρκετές γωνίες κλίσης, με σκοπό να αποκτήσουμε μια ολοκληρωμένη εικόνα της ενεργειακής τους συμπεριφοράς. Οι μετρήσεις πραγματοποιήθηκαν με τη βοήθεια του μηχανήματος PVPM 2540C το οποίο αποτυπώνει τη χαρακτηριστική ρεύματος-τάσης του προς μέτρηση πλαισίου για μια χρονική στιγμή (σε χρόνο δυο δευτερολέπτων περίπου), ενώ επιπλέον σημειώναμε την ακτινοβολία, τη θερμοκρασία του περιβάλλοντος, καθώς και την κλίση τοποθέτησής τους. Επίσης μελετούσαμε πώς επηρεάζει τη χαρακτηριστική καμπύλη I-V, και κατά συνέπεια την απόδοση, τυχόν σκίαση από παρακείμενο αντικείμενο. Ο προσανατολισμός των πλαισίων ήταν πάντα προς το Νότο, ώστε να έχουμε περισσότερες ώρες ηλιοφάνειας, διότι η Ελλάδα είναι χώρα του βόρειου ημισφαιρίου. Κατά την επεξεργασία των μετρήσεων καταλήξαμε στην βέλτιστη κλίση τοποθέτησης των πλαισίων ανά εποχή καθώς και σε μία βέλτιστη κλίση τοποθέτησης για όλο τo χρόνο για την περιοχή της Πάτρας. Επιπλέον, υπολογίσαμε με τη μέγιστη δυνατή ακρίβεια την ετήσια ενεργειακή απόδοση του κάθε πλαισίου για όλο το έτος και συγκρίναμε τα παραγόμενα αποτελέσματα. Τέλος, με τη βοήθεια του προγράμματος PV*Sol, κάναμε μια μοντελοποίηση του χρησιμοποιούμενου συστήματος για να συγκρίνουμε μ’ αυτή τα πειραματικά μας αποτελέσματα. / The aim of this diploma thesis is to understand deeply the operation of thin-film (specifically amorphous silicon and CIS ) modules and through the numerical data of measurements and calculations, to make a conclusion considering how the operation in real conditions can influence their produced power. Measurements of current and voltage have been realized on the roof of the building of the department of Electrical and Computer Engineering using an amorphous silicon and a CIS photovoltaic module of 32 and 75 W peak power respectively. The measurements took place once a week during one a year (May 2009-April 2010) and our goal was to obtain measurements under various conditions of radiation and temperature and for some tilt angles so that we acquire enough knowledge on their energy behaviour. The measurements were taken by the “pve PVPM 2540C“ device, which plots the characteristic curve of current and voltage of a module (in space of two seconds) and we also noted down the radiation, the ambient temperature, as well as the tilt angle of the modules. Moreover, we have tested how a possible natural shading from an adjacent object influences the characteristic I-V curve, and as a result the efficiency of the module. The orientation of the module was always South, in order to gain more hours of sunlight, as Greece is a country of the northern hemisphere. While processing the measurements, we found the optimal tilt angle of the modules per season as well as per year for Patras area. Moreover, we tried to calculate with the maximum possible accuracy, the annual energy yield by the two different types of modules and compare the results. Finally, by using the computer modelling system “PV*sol”, we tried to simulate our photovoltaic system, in order to compare the measured results to the experimental.
562

Jämförelse mellan CPT-sondering och CRS-försök med avseende på deformationsegenskaper / Comparison Between CPT-probing and CRS-Testing with Respect to Deformation Properties

Taloyan, Zoran January 2018 (has links)
Deformationsmoduler förklarar hur ett material eller ett område beter sig och deformeras vid olika laster. CRS-försök, komprimerar prover under en konstant deformationshastighet med erhållna moduler såsom: M0 och ML, med hjälp av rutinundersökning. Vid CPT-sondering penetrerar en konisk spets kontinuerligt genom en jordlagerföljd, med erhållen modul: Elasticitets-modul. Metoderna är väldigt olika vad gäller erhållna parametrar, moduler, deformationsgrupper och användning. CRS-försök genomförs laborativt, med prover tagna på vissa specifika djup, medan CPT-sondering genomförs in-situ med information om hela jordlagerföljden som ges. Att jämföra de olika metodernas moduler mellan varandra är inte möjlig, eftersom CONRAD som utvärderar och presenterar CPT resultat, inte utvärderar elasticitets-moduler för lera, utan för friktionsjord. Dem kompletterar varandra väldigt bra, då i områden som i Uppsala som har en med stor mäktighet av lera, visar med CRS-försök att det är lera som är närvarande för att sedan när CPT- sondering börjar registrera Elasticitets-moduler visar på att friktionsjord har påträffats. På så sätt kan deformationsegenskaper för en hel jordlagerföljd erhållas för en borrpunkt. Borrpunkter från Kronåsen och Kungsängen i Uppsala kommun, och Fyrklövern i Upplands Väsby kommun har undersökts med avseende på deformationsegenskaper och resultatet visar på stora skillnader i deras deformationsmoduler sinsemellan. / Deformation modules explains how a material or an area behave or deform when different amount of stresses act on it. CRS-testing, which compresses samples with a constant deformation rate, gives us modules like M0 and ML, with the help of routine examinations. CPT-probing, on the other hand, penetrate a conical tip through stratigraphy and gives us the elasticity module. These methods are very different in many ways, like what parameters, modules, deformation groups and use, are given. CRS-testing is conducted in a laboratory, with samples taken from specific depths, while CPT-probing is conducted in the field, with information about the whole stratigraphy is given. To directly compare these two methods modules are not possible. Due to CONRAD that evaluates and present CPT-probing results, does not evaluate elasticity modules for clay, but only for frictional soils. They complement each other very well due to in areas like Uppsala, which has a great depth of clay, shows with CRS-testing that clay is present but when CPT starts to register elasticity modules, shows that we moved in to frictional soil. With this, deformation properties can be shown for the whole stratigraphy in a drill point. Drill points from Kronåsen and Kungsängen in Uppsala municipality, and in Fyrklövern from Upplands Väsby municipality has been evaluated with respect to deformation properties and the results shows great differences in the deformation modules between themselves.
563

Power modules design and optimization for medium power of MMC inverters : high insulation voltage gate driver system and 3D packaging / Conception et optimisation de modules pour onduleur mmc de moyenne puissance : commande rapprochée à haute isolation galvanique et packaging 3d

Am, Sokchea 24 November 2016 (has links)
Dans cette recherche, l'auteur met l'accent à la fois sur une optimisation de la conception pour une (MV-MMC: Medium Voltage Modular Multilevel Converter) utiliser comme un DC/AC ou AC/DC et à deuxième fois sur la grille pour les modules IGBT qui sont utilisés dans ce type d'application. Par exemple, les convertisseurs de MMC sont utilisés dans les systèmes d'alimentation des navires électriques avec les buses de moyenne tension de courant continu (en anglais: medium-voltage direct current (MVDC)). Pour une telle application, selon le document IEEE, la tension du bus DC peut être jusqu'à 35kV. Par conséquent, les systèmes de commande rapprochée pour piloter le grille des modules IGBT pour les applications MVDC-MMC sont des principaux problèmes en termes d'architectures et des besoins de haute isolation galvanique. Ainsi, cette thèse fournit des solutions pour répondre à ces problèmes. L'étude inclut également les études d'un matériau diélectrique qui est utilisé comme matériau d'isolation. Les résultats des essais expérimentaux d'un matériau diélectrique proposé pour différentes épaisseurs des couches pour maintenir des niveaux de tension d'isolation sont également fournis pour valider clairement cette étude. En effet, un convertisseur MMC compose d'un certain nombre de cellules de conversion connectés en série. Une cellule (sous-module de convertisseur) est classiquement constitué de deux modules IGBT. Sur la base de la topologie de la cellule, l'architecture d'un pilote de grille contestée pour les modules de puissance à semi-conducteurs est proposée et comparée à celle classique en termes de besoins des niveaux de tension d'isolation galvanique, la taille de la cellule de convertisseur, etc. / In this research, the author focuses on both a design optimization for a Medium Voltage Modular Multilevel Converter (MV-MMC) use as a DC/AC or AC/DC converter and gate drivers systems for IGBT modules which are used in this kind of application. For example, the MMC converters are used in Medium-Voltage Direct Current (MVDC) electrical ship power systems. For such application, according to IEEE document, the DC bus voltage can be up to 35kV. Hence, gate drivers’ systems for IGBT modules for MVDC-MMC applications are major concerns in terms of architectures and insulation voltage capabilities. Thus, this dissertation provides solutions to answer these problems. The study also includes the studies of a dielectric material which is used as insulation material. The results of experimental tests of a proposed dielectric material for different layers thicknesses to sustain different insulation voltage levels are also provided to clearly validate this study. Actually, a MMC converter composes of a number of converter cells connected in series. One cell (converter’s sub-module) is classically composed of two IGBT modules. Based on the cell topology, a challenged gate driver’s architecture for power semiconductor modules is proposed and compared to the classical one in terms of high and low galvanic insulation voltage levels’ requirements, converter’s cell size, etc.
564

Desenvolvimento de um protótipo de sistema de suporte a decisão baseado em alertas vinculado a um sistema de informações sobre medicamentos cardiovasculares

Neves, Eugenio Rodrigo Zimmer January 1995 (has links)
O incentivo ao uso racional de medicamentos fator importante na melhoria das condições de saúde. A efetivação desta racionalidade, no entanto, esbarra tanto em fatores culturais como em fatores de escassez ou mesmo ausência de informação confiável. Os farmacêuticos, membros indispensáveis de qualquer equipe multidisciplinar de saúde, cumprem papel preponderante na disseminação deste conhecimento especializado. Com o objetivo de suprir as lacunas existentes quanto a qualidade da informação farmacológico-terapêutica existente no Brasil, este trabalho desenvolve um sistema de informações sobre medicamentos cardiovasculares aliado a um Sistema de Suporte a Decisão Baseado em Alertas, utilizando uma arquitetura que combina bases de dados relacionais com Medical Logical Modules. O sistema desenvolvido proporciona, a farmacêuticos e outros profissionais da área da saúde, não apenas consultas a informação, mas também sugestões e alertas contextuais referentes ao uso correto de medicamentos, contribuindo, assim, para o treinamento no próprio trabalho destes. / The rational use of drugs is an important factor to the health conditions improvement. The pharmacists are responsible for advising customers about the rational use of drugs, but this professional effort is limited by cultural factors, absence or lack of reliable infomation. The aim of this work is to support pharmacists through a cardiovascular medicine Information System attached to an Alert-based Decision Support System whose structure combines Medical Logical Modules and relational databases. The developed system not only provides the health professional and pharmacist with drug information, but also suggests or alerts them about the proper use of drugs as well it contributes to their in site training.
565

Sistemas de conversão de energia multiníveis obtidos através da interconexão de módulos de conversores estáticos de potência de dois níveis.

MAIA, Ayslan Caisson Norões. 27 August 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-08-27T19:35:43Z No. of bitstreams: 1 AYSLAN CAISSON NORÕES MAIA – TESE (PPGEEI) 2016.pdf: 13981392 bytes, checksum: 9ea0aa715fdf8400283e71381b49a21b (MD5) / Made available in DSpace on 2018-08-27T19:35:43Z (GMT). No. of bitstreams: 1 AYSLAN CAISSON NORÕES MAIA – TESE (PPGEEI) 2016.pdf: 13981392 bytes, checksum: 9ea0aa715fdf8400283e71381b49a21b (MD5) Previous issue date: 2016-02-22 / Nesse trabalho são apresentadas contribuições na área de identificação de sistemas representados em espaço de estados. É proposta uma metodologia completa para estimação de modelos que representem as principais dinâmicas de proessos industriais. O fluxo natural dos procedimentos de identificação consiste da coleta experimental dos dados, seguido pela esolha dos modelos candidatos e da utilização de um critério de ajuste que selecione o melhor modelo possível. Nesse sentido é proposta uma metodologia para estimativa de modelos em espaço de estados, utilizando excitações pulsadas. A abordagem desenvolvida combina algoritmos precisos e eficientes com experimentos rápidos, adequados a ambientes industriais. O projeto das excitações é realizado em tempo real, por meio de informações coletadas em um curto experimento inicial, baseado em uma única oscilação de uma estrutura realimentada por um relé. Esse mecanismo possibilita uma estimativa preliminar do atraso e da constante de tempo dominante do sistema. O método de identificação proposto é baseado na teoria de realizações de Kalman. É apresentada uma reformulação do problema de realizações clássico, para comportar sinais de entrada pulsados. Essa abordagem se mostra computacionalmente e cliente, assim como apresentar resultados semelhantes aos métodos de benchmark. A técnica possibilita também a estimativa de atrasos de transporte e a inserção de conhecimentos prévios por meio de um problema de otimização com restrições via LMI Linear Matrix Inequalities. Em muitos casos, somente as caraterísticas principais dos sistema são relevantes em um projeto de sistema de controle. Portanto é proposta uma técnica para obtenção de modelos de primeira ordem com atraso, a partir da redução de modelos balanceados em espaço de estados. Por fim, todas as contribuições discutidas nesse trabalho de teses não validadas em uma série de plantas experimentais em salas de laboratório. Plantas essas, projetadas e construídas com o intuito de emular o cotidiano operacional de instalações industriais reais. / Static converters are a widely used equipment in power systems to control the electrical energy low between sources and loads. In this context, it is observed a demand for converters topologies that generate high quality waveforms and are capable of supplying loads with ever larger powers. In high power applications such as industrial and power systems, the development of a special class of converters topologies, denominated multilevel converters, has been widely recognized as a viable solution to overcome the operational limits of semiconductor devices. In this work are developed and analyzed multilevel structures of type DC-AC applied to the six-phase machines drives and of type AC-DC-AC feeding singlephase and three-phase loads. These topologies are obtained by interconnecting two-level converters modules in order to optimize the system: reduction of losses in the semiconductor devices, harmonic distortion of the signals and ratings of voltage and/or current in the power switches. For this investigation were performed steady state analyzes, where the operatinglimits of the structures to the imposed control conditions and the behavior of the fundamental component of voltage and current are evaluated. In addition, for each investigated topology, were developed: dynamic models, PWM techniques, control strategies, simulation results and experimental results. The impact of this optimization is quanti ed by calculating the THD and WTHD of the current and voltage signals generated by the converter and by estimating losses in the semiconductor devices. Finally, a comparative study is done using conventional converters as reference in order to evaluate the performance of the proposed topologies
566

Identification of personalized multi-omic disease modules in asthma

Martínez Enguita, David January 2018 (has links)
Asthma is a respiratory syndrome associated with airflow limitation, bronchial hyperresponsiveness and inflammation of the airways in the lungs. Despite the ongoing research efforts, the outstanding heterogeneity displayed by the multiple forms in which this condition presents often hampers the attempts to determine and classify the phenotypic and endotypic biological structures at play, even when considering a limited assembly of asthmatic subjects. To increase our understanding of the molecular mechanisms and functional pathways that govern asthma from a systems medicine perspective, a computational workflow focused on the identification of personalized transcriptomic modules from the U-BIOPRED study cohorts, by the use of the novel MODifieR integrated R package, was designed and applied. A feature selection of candidate asthma biomarkers was implemented, accompanied by the detection of differentially expressed genes across sample categories, the production of patient-specific gene modules and the subsequent construction of a set of core disease modules of asthma, which were validated with genomic data and analyzed for pathway and disease enrichment. The results indicate that the approach utilized is able to reveal the presence of components and signaling routes known to be crucially involved in asthma pathogenesis, while simultaneously uncovering candidate genes closely linked to the latter. The present project establishes a valuable pipeline for the module-driven study of asthma and other related conditions, which can provide new potential targets for therapeutic intervention and contribute to the development of individualized treatment strategies.
567

Conception de circuits RF en CMOS SOI pour modules d'antenne reconfigurables / SOI CMOS circuit design for reconfigurable antenna modules

Nicolas, Dominique 03 May 2017 (has links)
Dans le contexte des applications mobiles, les contraintes de conception des chaînes d'émission toujours plus performantes et de taille réduite demandent de compenser la forte sensibilité des caractéristiques des antennes à leur environnement. En particulier, il est nécessaire de maîtriser l'impédance de l'antenne pour optimiser l'efficacité énergétique de la chaîne de transmission. Or, les solutions actuelles se montrent encombrantes. Dans cette thèse, plusieurs pistes basées sur l'implémentation de condensateurs variables ont été étudiées et ont conduit à la réalisation et la caractérisation de nouveaux dispositifs RF intégrés à même de participer à cet effort. Après une présentation du contexte et de l'état de l'art, nous proposons une étude de condensateurs variables basés sur la technique des capacités commutées. L'étude a permis la réalisation de deux condensateurs variables en technologie CMOS SOI 130 nm pour des applications d'adaptation d'impédance et d'antenne agile en fréquence. Un premier démonstrateur d'antenne fente agile en fréquence visant les bandes LTE situées entre 500 MHz et 1 GHz et utilisant ce type de condensateur a ensuite été réalisé puis validé. Un système d'accord permettant de corriger les désadaptations d'antenne a ensuite été étudié et a donné lieu à la réalisation de deux circuits intégrés en technologie CMOS SOI 130 nm. Le premier circuit est un détecteur d'impédance capable de fonctionner sur une gamme de puissance étendue de 0-40 dBm pour une plage de fréquences de 600 MHz-2,4 GHz. Le deuxième circuit intègre une version améliorée du détecteur avec un circuit d'adaptation variable autorisant la réalisation d'un système d'accord d'antenne autonome et compact représentant une avancée importante par rapport à l'état de l'art. / In the context of mobile applications, design constraints on always more performant and size-constrained emitting front-ends ask to compensate for strong sensitiveness of antennas characteristics to their environment. In particular, it is necessary to control the antenna impedance in order to optimize the energy efficiency of the transmitting front-end. Yet, current solutions are bulky. I this thesis, several ways based on the implementation of variable capacitors have been studied and have led to the design and characterization of new integrated RF devices that can participate to this effort. After a presentation of the context and the state-of-the-art, we propose a study of switched-capacitor-based variable capacitors. This study allowed the design of two variable capacitors in 130 nm CMOS SOI technology for impedance matching and frequency-agile antenna applications. Then, a first demonstrator module of a frequency-agile antenna aiming for 500 MHz-1 GHz LTE bands and using this type of capacitor has been designed and validated. A tunable system allowing the correction of antenna mismatch has then been studied and has led to the design of two 130 nm CMOS SOI integrated circuits. The first circuit is an impedance detector that is able to work on a 0-40 dBm power range and a 600 MHz-2.5 GHz frequency range. The second integrated circuit includes an improved version of the detector with a tunable matching network which both allow the fabrication of an autonomous, compact antenna tunable system showing significant progress relative to the state-of-the-art.
568

Desenvolvimento de um protótipo de sistema de suporte a decisão baseado em alertas vinculado a um sistema de informações sobre medicamentos cardiovasculares

Neves, Eugenio Rodrigo Zimmer January 1995 (has links)
O incentivo ao uso racional de medicamentos fator importante na melhoria das condições de saúde. A efetivação desta racionalidade, no entanto, esbarra tanto em fatores culturais como em fatores de escassez ou mesmo ausência de informação confiável. Os farmacêuticos, membros indispensáveis de qualquer equipe multidisciplinar de saúde, cumprem papel preponderante na disseminação deste conhecimento especializado. Com o objetivo de suprir as lacunas existentes quanto a qualidade da informação farmacológico-terapêutica existente no Brasil, este trabalho desenvolve um sistema de informações sobre medicamentos cardiovasculares aliado a um Sistema de Suporte a Decisão Baseado em Alertas, utilizando uma arquitetura que combina bases de dados relacionais com Medical Logical Modules. O sistema desenvolvido proporciona, a farmacêuticos e outros profissionais da área da saúde, não apenas consultas a informação, mas também sugestões e alertas contextuais referentes ao uso correto de medicamentos, contribuindo, assim, para o treinamento no próprio trabalho destes. / The rational use of drugs is an important factor to the health conditions improvement. The pharmacists are responsible for advising customers about the rational use of drugs, but this professional effort is limited by cultural factors, absence or lack of reliable infomation. The aim of this work is to support pharmacists through a cardiovascular medicine Information System attached to an Alert-based Decision Support System whose structure combines Medical Logical Modules and relational databases. The developed system not only provides the health professional and pharmacist with drug information, but also suggests or alerts them about the proper use of drugs as well it contributes to their in site training.
569

A Memory Allocation Framework for Optimizing Power Consumption and Controlling Fragmentation

Panwar, Ashish January 2015 (has links) (PDF)
Large physical memory modules are necessary to meet performance demands of today's ap- plications but can be a major bottleneck in terms of power consumption during idle periods or when systems are running with workloads which do not stress all the plugged memory resources. Contribution of physical memory in overall system power consumption becomes even more signi cant when CPU cores run on low power modes during idle periods with hardware support like Dynamic Voltage Frequency Scaling. Our experiments show that even 10% of memory allocations can make references to all the banks of physical memory on a long running system primarily due to the randomness in page allocation. We also show that memory hot-remove or memory migration for large blocks is often restricted, in a long running system, due to allocation policies of current Linux VM which mixes movable and unmovable pages. Hence it is crucial to improve page migration for large contiguous blocks for a practical realization of power management support provided by the hardware. Operating systems can play a decisive role in effectively utilizing the power management support of modern DIMMs like PASR(Partial Array Self Refresh) in these situations but have not been using them so far. We propose three different approaches for optimizing memory power consumption by in- ducing bank boundary awareness in the standard buddy allocator of Linux kernel as well as distinguishing user and kernel memory allocations at the same time to improve the movability of memory sections (and hence memory-hotplug) by page migration techniques. Through a set of minimal changes in the standard buddy system of Linux VM, we have been able to reduce the number of active memory banks significantly (upto 80%) as well as to improve performance of memory-hotplug framework (upto 85%).
570

Temperature Coefficients and Thermal Uniformity Mapping of PV Modules and Plants

January 2016 (has links)
abstract: The operating temperature of photovoltaic (PV) modules is affected by external factors such as irradiance, wind speed and ambient temperature as well as internal factors like material properties and design properties. These factors can make a difference in the operating temperatures between cells within a module and between modules within a plant. This is a three-part thesis. Part 1 investigates the behavior of temperature distribution of PV cells within a module through outdoor temperature monitoring under various operating conditions (Pmax, Voc and Isc) and examines deviation in the temperature coefficient values pertaining to this temperature variation. ANOVA, a statistical tool, was used to study the influence of various factors on temperature variation. This study also investigated the thermal non-uniformity affecting I-V parameters and performance of four different PV technologies (crystalline silicon, CdTe, CIGS, a-Si). Two new approaches (black-colored frame and aluminum tape on back-sheet) were implemented in addition to the two previously-used approaches (thermally insulating the frame, and frame and back sheet) to study temperature uniformity improvements within c-Si PV modules on a fixed latitude-tilt array. This thesis concludes that frame thermal insulation and black frame help reducing thermal gradients and next best viable option to improve temperature uniformity measurements is by using average of four thermocouples as per IEC 61853-2 standard. Part 2 analyzes the temperature data for two power plants (fixed-tilt and one-axis) to study the temperature variation across the cells in a module and across the modules in a power plant. The module placed in the center of one-axis power plant had higher temperature, whereas in fixed-tilt power plant, the module in north-west direction had higher temperatures. Higher average operating temperatures were observed in one-axis tracking as compared to the fixed-tilt PV power plant, thereby expected to lowering their lifetime. Part 3 focuses on determination of a thermal model coefficients, using parameters similar to Uc and Uv thermal loss factors used in PVsyst, for modules of four different PV technologies experiencing hot-desert climate conditions by statistically correlating a year-long monitored data. Thermal models help to effectively quantity factors influencing module temperatures to estimate performance and energy models. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2016

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