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Degradation of Photovoltaic Modules
Poledník, Tomáš ; Křivík, Petr (referee) ; Vaněk, Jiří (advisor)
The bachelor diploma thesis is focused on the constructional technology of the solar modules as well as on the problems of the induced degradation under the influence of the potential. It specifies the key issues and possible elements that influence the effect of environment with regard to possible causes of the origin of degeneration. The thesis includes the description of measuring of the polycrystalline and monocrystalline technologies that are resistant to the leading potential. Furthemore, the measuring was carried out on the chosen testing pieces that had been affected by the degradation of the output
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Study of photovoltaic nanostructures using microscopy methods
Hertl, Vít ; Valenta,, Jan (referee) ; Fejfar, Antonín (advisor)
V této diplomové práci je nejprve ve zkratce uvedena teorie fyziky solárních článků, kde jsou zmíněny klíčové procesy ovlivňující účinnost konverze slunečního záření na elektrickou energii. Dále je předložena rešerše o fotovoltaických nanostrukturách (nanodráty, nanokrystaly), jejichž implementací je možné účinnost solárních článků zvýšit. V přehledu experimentálních technik ke zkoumání fotovoltaických nanostruktur je důraz kladen zejména na korelativní měření pomocí SEM a AFM, vodivostního AFM, měření EBIC a mikroskopické měření elektroluminiscence. V experimentální části jsou předloženy výsledky měření struktur mikrokrystalického křemíku, vzorku hetero-přechodového Si solárního článku s kontakty na zadní straně (IBC-SHJ z projektu NextBase) a V-pitů vzorku InGaN/GaN kvantových jam. Měření elektroluminiscence bylo provedeno na vzorcích III-V polovodičů (InGaP, GaAs). Byly vypočítány jinak těžko dostupné charakteristiky III-V tandemových solárních článků pomocí elektroluminiscence a srovnání vlastností IBC-SHJ zjištěných pomocí mikroskopického měření elektroluminiscence a EBIC. Provedením experimentů bylo zjištěno, jakým způsobem se dělí proud vybuzený svazkem elektronů mezi hrot AFM a vzorek mikrokrystalického křemíku.
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Preparation of white-electroluminescent panel
Guricová, Patrícia ; Novák, Vítězslav (referee) ; Vala, Martin (advisor)
The aim of this work is to prepare white emitting electroluminescent device using printing techniques. Preparation options are discussed in order to minimise reabsorption in the phosphor layer and thus increase the overall radiation intensity. Model devices were prepared, the active layer of phosphor printed in a pattern of stripes and circles. The impact of the applied voltage and frequency was studied on these devices. It has been shown that, in terms of white emission, it is better to use the patterns compared to the phosphor mixture. The ratios of emission intensities of both phosphors are more even, therefor closer to the white light. The output of this work is model designed to determine the necessary frequency area for obtaining the white emission of ACEL device.
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Electronic ballast for power LEDs
Vágner, Richard ; Martiš, Jan (referee) ; Červinka, Dalibor (advisor)
This diploma thesis deals with design of power LED driver. This driver contains electronic ballast circuits, converters, filters and control circuits. Overviews of circuits used in practice are listed along with analysis of power LED and considering options for selecting an appropriate design solution. Principles of creating the device, structure and problems of current source are described in thesis. Including detailed overview of converters, ballasts and topologies used in lighting systems with the selection of a suitable solution for the final device with an output power of 50 W. The thesis includes cooling dimensioning for selected power LEDs, input circuit with EMI filter, bridge rectifier, boost converter and flyback converter with pulse transformer.
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Reconstruction of the Pohorelec at the JAMU Stage Design Studio
Čech, Daniel ; Špiller, Martin (referee) ; Guzdek, Adam (advisor) ; Lavický, Miloš (advisor)
The aim of the Bachelor thesis was to renew and rebuild the building of the former Supreme state prosecutor to the place for The Stage design of Janáček Academy of Music and Performing Arts in Brno and The Rectorate od Janáček Academy. The building is located on the corner of the busy streets Jánská, Kobližná and Pohořelec where it forms a rather drab end point of these streets. The object was built in the post World war II period and carries features of late functionalism. The building has been abandoned since 90s. The ground floor was used for commerce, the underground floor for technical equipment of the building and other upper floors were purely administrative. The building has one underground floor and seven above-ground floors. In the ground floor were designed a public café and exhibition spaces. On the second to the fourth floor there are administrative places for the Janáček Academy Rectorate. On the fifth to the seventh floor the are spaces for students of the Stage design. In the new eight floor there is a background for the Light design. The main focus of the work was to restore life and create a functional and aestetically friendly environment. This was achieved by changing the internal layout where some dividing structures were removed, including the vertical connections of the floors and finally the use of glass partitions.The layout is now more open, lighter and airy. A main element of the reconstruction is the extension of the next floor, which has increased the space for students and employees and confirmed the unclear verticality of the building. The entire extension has more dominant look, but with natural respect to the surrounding buildings. The superstructure fasade consists of pre-installed electroluminescent panels with a holographic foil. This foil produces rainbow effects on the facade and reflects light, relieving the mass. At night, thanks to electroluminescent wires, the extension shines and highlights the happenings inside th
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Analyse of photovoltaic solar cells by the photoluminescence method
Richter, Vladimír ; Bača, Petr (referee) ; Vaněk, Jiří (advisor)
This diploma thesis deals with the issues of photovoltaic cells. The main aim of this thesis is to introduce the principles of operation of solar cells and methods of detection of defects affecting their quality. The first part is about the functional properties of silicon cells and it also examines the possibilities of detecting the defects of these structures. It also describes the most commonly used modern diagnostic methods. In the next part, practical tests of photovoltaic cells using the methods electroluminescence and photoluminescence are performed. These methods are based on the excitation of luminescence radiation of the silicon material by the external light source.
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Long-term monitoring of parameters of photovoltaic modules
Kladiva, Roman ; Solčanský, Marek (referee) ; Gvritishvili, Roman (advisor)
This thesis deals with the influence of degradation mechanisms to change the parameters of photovoltaic panels. The aim of the study was the long-term monitoring of selected solar modules, comparing their parameters with measurements from previous years and the evaluation of degradation mechanisms on their properties. The theoretical part is focused on the description of the monitored parameters and defects Panel, are discussed measuring methods by which the modules were monitored. Experimental part then consists of measuring modules individual test methods. The measured values were subsequently constructed graphical dependence, and the results were compared with measurements from previous years. The last part of the thesis is devoted to evaluation of the degradation of PV modules.
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Analytic method of solar panel and systems
Kopunec, Vít ; Veselý, Aleš (referee) ; Vaněk, Jiří (advisor)
The aim of the diploma work is to introduce analytical methods concerning solar panels and systems. Firstly, the attention is drawn to a principle of photovoltaic conversion including an explanation of photoelectric phenomenon as well as the issue of P-N junction considered to be the fundamental building block of a solar cell. With respect to the fact that the diploma work is to be focused on testing of solar panels and the identification of defects in solar cells, the work describes individual solar cells, solar panels as well as individual methods of defect identification. Secondly, the work includes sections dealing with the assessment of the measurement performed by using electroluminescence method as well as the measurement method of volt-ampere parameters. The last section of the work includes the assessment of solar panel aging after one-year performance using the electroluminescence measurement method.
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Influence of temperature on light-technical parameters of LED
Sláma, Pavel ; Štěpánek, Jaroslav (referee) ; Pavelka, Tomáš (advisor)
This thesis deals with LEDs and how temperature influences their parameters. In the first part it is analyzed how semiconductors and semiconductor junctions work, which is fundamental for understanding mechanisms of diodes. Next up is description of electroluminescence and basic description of physical principles, on which it works. Following part is supposed to introduce reader to electro-technical parameters and powering possibilities of LEDs. Following chapter focuses on description of lightning-technical parameters. It aims to describe their meaning and their relation to LEDs. Next part is about influence of temperature. Firstly, it names the parameters which are altered by temperature change. Follows the description of thermal management and its influence on right behavior of LED diodes. The last part contains construction of measuring workplace for analyzing temperature influence on lightning-technical parameters of LEDs. Measurement of chosen electrical and lightning parameters follows up.
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