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Fotovoltaické články pro napájení nízkoodběrových elektronických zařízení / Photovoltaic celss for supplying low-demand electronic devicesSlivka, Ján January 2013 (has links)
The aim of master’s thesis was to develop a method for long-term measuring the influence of temperature on photovoltaic cells and lithium-polymer batteries and to design such measuring system. System was assembled on universal printed circuit board. It consisted of circuits for measuring temperature, illuminance and charging circuit, which charged battery with capacity 110 mAh. The PV cell BSK-SP9261 was used as source. Voltages was recorded by data acquisition device NI-USB 6009 and loged in program developed in LabVIEW 2012 enviroment. Afterwards, temperature, illuminance, voltage on PV cell and internal resistance of battery were computed.
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Revising installed photovoltaic capacities on emerging markets by analysing customs dataOller Westerberg, Amelia January 2020 (has links)
The global solar PV market is growing fast, and so is the production and trade with photovoltaic products and peripherals. Until now, the largest development has taken place in highly developed and electrified countries with good administrative control over their electricity system. Recently, however, new markets in developing countries have become increasingly relevant in terms of market share, system sizes and installed capacities. Statistics from these types of countries are often weak or non-existent, leading to problems for global organizations such as the International Energy Agency (IEA) or the International Renewable Energy Agency (IRENA), whose task is to follow, analyze and document named development. In this report, a method is presented in which customs data monitored by the ‘Market Analysis and Research’ section of the International Trade Centre, an agency of UN’s World Trade Organization, is analyzed and converted into annual installed PV capacity volumes. By complementing the basic data from the customs database with price statistics from IEA PVPS task 1 along with national module production data from IEA PVPS task 1 and the RTS cooperation a data conversion is executed. The method has been improved incrementally, where different assumptions have been modified or added, so that the data conversion of exported and imported PV products, expressed in dollar per yearly quarter, match the official statistics of annual installed capacity for a number of reference countries with comprehensive PV capacity statistics. The sensitivity analysis shows that the method is sensitive to the accuracy of the annual domestic national PV module production data and to price changes of Chinese PV modules. For countries with accurate PV module production data, or countries with no module production, the method seems to be able to estimate the annual installed capacity in 2018 with an average difference of 21% and a maximum difference of ±38% and a total average difference of 12%, 17% and 11% for 2016, 2017 and 2018 respectively. By implementing this method, an estimate on yearly installed capacities can be generated in all countries connected to the UN customs database and where the domestic module production is known. This gives the opportunity to at least get an assessment of how much PV that has been installed in developing countries that lack official statistics about their domestic PV market. The regions with the lowest existing data coverage in the world have been determined to be Africa and the Middle East. When applying the method on countries in Africa and the Middle East, larger capacities than the reference data were obtained.
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The potential for centralized photovoltaicsystems in SwedenKARLSSON, REBECCA, NILSENG, EVA January 2016 (has links)
Considering the long term target set by the Swedish government of having an energy system basedexclusively on renewable sources, the potential for different renewable sources need to beinvestigated. When analyzing the sources used for electricity production in Sweden today, solarPV represents a very small share. This relatively small share also mainly consists of grid-connecteddistributed PV systems, and to analyze the possibilities of making solar energy a larger share inthe electricity production in Sweden this study will focus on grid-connected centralized PV farms.The main purpose of the study is to identify the potential for grid-connected centralized PVsystems for large scale production in Sweden. This will include an identification of the mostimportant key factors influencing the profitability, an investment calculation to be aware of theprofitability, a prediction of the future development of the PV industry in Sweden and lastly themain challenges that the PV industry is facing.To conduct this study a collaboration with Vattenfall Vind AB has been made, where a case studybased on three specific locations has been implemented when analyzing both the profitability andthe key factors. These three cases are based on places where Vattenfall has existing wind farms orhas assigned for upcoming ones. These areas could be seen as a potential benefit since the companyalready has started to inspect the land area, and that wind and PV farms might be able to sharenecessities such as infrastructure.The results of the study mainly indicate that the PV industry most likely will continue develop andgrow, but the profitability of investing in grid-connected centralized PV farms does not lookpromising today or in the next coming years. This mainly due to low prices for electricity anduncertainties in the future development of the financial support policy. The location is also veryimportant for this type of installation. There are places in southern Sweden with enough insolation,but these areas can be seen as limited. To make solar energy a larger share of the electricityproduction in Sweden in a profitable way today, more investments should be made in gridconnecteddistributed PV systems rather than grid-connected centralized PV farms. PV farms forlarge scale production might though be more profitable in the future when the prices for modulesand inverters will decrease further and when the spot price increases.
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Leistungsoptimierung von Photovoltaikanlagen: Erweiterung eines Laborversuchsstands für die aktuelle ForschungEckert, Scott 27 May 2022 (has links)
No description available.
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Analysis of the Expected Development of Solar PV Market in TurkeySabah, Ibrahim January 2014 (has links)
Electricity generation through solar photovoltaic (PV) technology has been one of the leading renewable energy generation options in the global arena and in many countries that are working to address increasing energy demand and high fuel import dependencies. Due to the feed in tariff (FIT) amendment in 2011 and decreasing costs in global PV sector, the interest in this emerging market is quickly increasing in Turkey. The aim of this thesis is to explore the prospects for development of the solar PV market in Turkey, considering residential, commercial and utility scale PV systems with rooftop or ground mounted installations. The economic situation, the energy profile, regulatory framework for solar energy and the market conditions in the country were researched. The ultimate purpose was to assess the overall conditions to attract investors, and estimate the development of the solar PV market growth in Turkey particularly in the next few years. High irradiation levels, limited domestic energy resources and high interest in license applications suggest a big potential for solar PV electricity in Turkey. However, the regulatory framework is not yet suitable for a fast growth of this emerging solar PV market in the country due to lack of political support and experience in related government functions. Despite the high interest and demand for commercial systems, the solar PV market in Turkey is expected to grow linearly as a start. This contrast with precedents in leading European markets, which experienced exponential growth at the beginning. This study shows that there is a need for performance improvement within the regulative authorities, time for stakeholders to experience the market and more comprehensive and stable legislation. However, in the long term, solar PV technology is expected to gain high competitive advantage due to improving financial conditions in the country, increase in electricity prices (e.g. grid parity has already been reached for residential systems), and cost reductions for PV components around the world.
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Comparative study of polygeneration systems for commercial buildings / Jämförelsestudie av polygenereringssytem för kommersiella byggnaderKarem, Agri, Kristiansson, Marcus January 2020 (has links)
In recent times the problems regarding global warming and climate change have become increasingly relevant in our society. Public attention is growing due to seemingly larger and more severe natural disasters each year and the search for solutions to these problems is greater than ever. Humanity is facing a lot of environmental challenges, but one could argue that the increasing rate of greenhouse gas emissions related to energy production and use is the main focus. This study focuses on how electricity generating and storage technologies can be installed for different types of buildings and businesses to maximize economic benefits and at the same time reduce dependency on grid bought electricity. The buildings in the analysis will have prior solar PV systems installed ranging from 35 kW to 254.8 kW in capacity. Three different buildings within this interval have been chosen and have the solar PV capacity of 35.84 kW, 143.36 kW and 254.8 kW. These buildings have been chosen to get three different load profiles that are as different as possible, given the available data. The study concludes that only using solar PV is the financially most profitable system configuration for all three buildings, rated by maximum IRR. Both wind power and batteries have a negative impact on IRR for all buildings. The building with the least changes in day-to-day peak demand benefited the most from solar PV. Wind power affects the demand in a similar way as solar PV, however batteries added more value to a building with a less consistent load curve. / På senare tid har problemen med global uppvärmning och klimatförändringar blivit alltmer relevanta i vårt samhälle. Allmänhetens uppmärksamhet växer på grund av till synes större och allvarligare naturkatastrofer varje år och sökandet efter lösningar på dessa problem är större än någonsin. Mänskligheten står inför många miljömässiga utmaningar, men det går att hävda att den ökande andelen växthusgasutsläpp relaterade till energiproduktion och användning är huvudfokus. Denna studie fokuserar på hur elproduktionens- och lagringsteknologier kan installeras för olika typer av byggnader och företag för att maximera ekonomiska fördelar och samtidigt minska beroendet av köpt el från elnätet. Byggnaderna i analysen har tidigare installerade solcellsanläggningar som sträcker sig från 35 kW till 254.8 kW. Tre olika byggnader inom detta intervall har valts och för dessa var solenergikapaciteten 35.84 kW, 143.36 kW och 254.8 kW. Dessa byggnader har valts för att få tre olika elförbrukningsprofiler som är så olika som möjligt med tanke på den tillgängliga datan. Studien drar slutsatsen att användningen av endast PV är den ekonomiskt est lönsamma systemkonfigurationen för alla tre byggnader, rankad efter maximal IRR. Både vindkraft och batterier påverkar IRR negativt för alla byggnaderna. Byggnaden med minst förändringar i det dagliga toppbehovet gynnades mest av solceller. Vindkraft påverkar elbehovet på liknande sätt som PV, men batterierna däremot gav mer värde till en byggnad med en förbrukningsprofil som var mindre konsekvent.
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Electrical Properties Degradation of Photovoltaic Modules Caused by Lightning Induced VoltageJiang, Taosha 17 May 2014 (has links)
Lightning is one of the main factors that cause Photovoltaic (PV) systems to fail. The PV modules inside PV systems, like any other electric equipment, will be degraded under electrical stress. The effect of electrical degradation of the PV modules caused by lightning induced voltage has been rarely reported. In the dissertation, the electrical properties degradation of a polycrystalline silicon module was studied. Firstly, lightning impulse voltages of positive polarity ranging from low to high are applied on different groups of the testing modules. All these lightning impulse voltage tests are conducted in the same experimental condition except for their stress voltage magnitudes. The maximum power output, I-V characteristics, and dark forward I-V curve are measured and reported periodically during the lightning impulse voltage tests. By comparing the maximum output power and changes in the internal electrical properties, it could be concluded that lightning impulse voltages, even medium voltage levels, will cause degradation to the sample. The relationship of the maximum output power and the number of applied impulses for different testing voltage levels are compared. An analysis of the electrical property changes caused by the lightning impulse voltages is presented. Secondly, a group of samples are tested with lightning impulse voltage of negative polarity. A comparison of the impulse voltage aging effects at the same voltage level with positive polarity is made. The maximum power output drop caused by positive and negative lightning impulses are compared. Laboratory results revealed that positive and negative lightning impulses will not only influence the degree of degradation, but also lead to different electrical property changes. Finally, a comparison of the effect of lightning impulses combined with other stress factors are discussed. The study simulates a field-aged sample’s behavior at lightning impulse voltage testing conditions. The result suggests that the degradation caused by lightning impulse voltage is greatly accelerated when the sample has bubbles and delamination. Electrical breakdown of the module is caused by the failure of the insulation.
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PV Hosting Analysis and Demand Response Selection for handling Modern Grid Edge CapabilityAbraham, Sherin Ann 27 June 2019 (has links)
Recent technological developments have led to significant changes in the power grid. Increasing consumption, widespread adoption of Distributed Energy Resources (DER), installation of smart meters, these are some of the many factors that characterize the changing distribution network. These transformations taking place at the edge of the grid call for improved planning and operation practices. In this context, this thesis aims to improve the grid edge functionality by putting forth a method to address the problem of high demand during peak period by identifying customer groups for participation in demand response programs, which can lead to significant peak shaving for the utility. A possible demand response strategy for peak shaving makes use of Photovoltaic (PV) and Battery energy storage system (BESS). In the process, this work also examines the approach to computation of hosting capacity (HC) for small PV and quantifies the difference obtained in HC when a detailed Low voltage (LV) network is available and included in HC studies. Most PV hosting studies assess the impact on system feeders with aggregated LV loads. However, as more residential customers adopt rooftop solar, the need to include secondary network models in the analysis is studied by performing a comparative study of hosting capacity for a feeder with varying loading information available. / Master of Science / Today, with significant technological advancements, as we proceed towards a modern grid, a mere change in physical infrastructure will not be enough. With the changes in kinds of equipment installed on the grid, a wave of transformation has also begun to flow in the planning and operation practices for a smarter grid. Today, the edge of the grid where the customer is interfaced to the power system has become extremely complex. Customers can use rooftop solar PV to generate their own electricity, they are more informed about their consumption behavior due to installation of smart meters and also have options to integrate other technology like battery energy storage system and electric vehicles. Like with any good technology, adoption of these advancements in the system brings with itself a greater need for reform in operation and planning of the system. For instance, increasing installation of rooftop solar at the customer end calls for review of existing methods that determine the maximum level of PV deployment possible in the network without violating the operating conditions. So, in this work, a comparative study is done to review the PV hosting capacity of a network with varying levels of information available. And the importance of utilities to have secondary network models available is emphasized. With PV deployed in the system, enhanced demand response strategies can be formulated by utilities to tackle high demand during peak period. In a bid to identify customers for participation in such programs, in this work, a computationally efficient strategy is developed to identify customers with high demand during peak period, who can be incentivized to participate in demand response programs. With this, a significant peak shaving can be achieved by the utility, and in turn stress on the distribution network is reduced during peak hours.
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Study of Photovoltaic SystemRakotomananandro, Falinirina F. 22 July 2011 (has links)
No description available.
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Comparison and Design of High Efficiency Microinverters for Photovoltaic ApplicationsDominic, Jason 14 January 2015 (has links)
With the decrease in availability of non-renewable energy sources coupled with the increase in the amount of energy required for the operation of personal electronic devices there has been an increased focus on developing systems that take advantage of renewable energy sources. Renewal energy sources such as photovoltaic (PV) panels have become more popular due to recent developments in PV panel manufacturing that decreases material costs and improves energy harvesting efficiency. Since PV sources are DC sources power conversion stages have to be used in order to interface this power to the existing electrical utility system.
The structure of large scale PV systems usually consists of several PV panels connected in series to achieve a high input source voltage that can be fed into a high power centralized DC-AC inverter. The drawback to this approach is that when the PV panels are subjected to less than ideal conditions. If a single PV panel is subjected to drastically less solar irradiation during cloud conditions, then its output power will drop dramatically. Since this panel is series connected with the other PV panels, their current output is also dragged low decreasing the power output of the system. Algorithms that have the power converter operate at different input conditions allow the system to operate at a maximum power point (MPP), however this only allows the system to operate at a higher power point and not the true MPP.
To get around this limitation a new PV system implementation was created by giving each panel its own DC-AC power conversion system. This configuration gives each panel the ability to operate at its own MPP increasing the total system energy harvest. Another advantage of the single panel DC-AC microinverter power conversion stage is that the outputs are parallel connected to the utility grid easily allowing the ability to expand the system without having to shut down the entire system.
The most prevalent implementation of the microinverter consists of a single power converter that uses the PV low voltage DC and outputs high voltage AC. In order to ensure that the double line AC ripple does not propagate to the PV panel a large bank of electrolytic capacitors are used to buffer the ripple. There is concern that the electrolytic capacitor will degrade over time and affect the system efficiency. To get around having to use electrolytic capacitors a two stage microinverter has been proposed. The two stage microinverter consists of a DC-DC converter that steps up the low DC voltage of the PV panel to high voltage DC and the second stage is a DC-AC inverter that takes the high voltage DC and converts it to high voltage AC. There is a capacitor that connects the two power converter stages called the DC link capacitor which can buffer the double line energy ripple without using electrolytic capacitors.
This thesis focuses on the review of several DC-AC inverter topologies suitable for use in PV microinverter systems. Operation capabilities such as common mode noise and efficiency are compared. The main focus of the review is to determine the optimal DC-AC inverter using the performance metrics of cost, efficiency and common mode performance. A 250 W prototype is built for each inverter topology to verify its performance and operation. / Master of Science
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