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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.
121

Facelift EDU / Facelift PDU

Růžičková, Tereza January 2020 (has links)
The theme of the diploma thesis is the solution of the pre-plant zone of the Dukovany nuclear power station. Creating a vision of how this space could develop further in the next 50 years and how it could work in a transitional phase during the construction of a new nuclear power plant unit. The subject of the thesis is the elaboration of an architectural study, which is based on an urban study. Urban study was processed within the framework of the pre-diploma thesis and solved mainly the overall problems of this area, the new transport connection, and the functional division of the whole area. The area was divided into three functional units, namely the transport zone, the administrative zone and the sports and education zone. At present, there are a lot of small structurally and functionally unsuitable buildings in this area. The diploma thesis deals with the design of new buildings with a clear functional use in the administrative zone, in the area in front of the main gatehouse. A new representative square was created, and three buildings are designed around it. The dominant feature of the whole area was a high-rise office building near the gatehouse. In front of the office building, towards the main road, the service building I was designed, which contains business and healthcare services. On the other side of the square was located the service building II, where there are technical services, such as workshops, warehouses and metrology. The last building solved within the diploma thesis is the building of sports and locker rooms of suppliers, which is designed behind the square near the greenery. New building copies mass of the only preserved building in this area, namely the building of the information centre. The designed building has a fitness centre and locker rooms of external workers of the power plant.
122

Posouzení možnosti připojení kogenerační výrobny 138 MW v Prostějově / The assessment of connectivity 138 MW combined heat and power plant in Prostějov

Vacek, Tomáš January 2011 (has links)
The goal of this project is to test the possibility to connect the Cogenerational generation of power 138 MW (still in the development stage) to the control room 110 kV in Prostejov production. This merge would product the electrical energy as well as the heat energy for all local area. In this dissertation we will be considering the solution of the steady state (stationary state) of system with the voltage level of 110kV, as well as the influence of the generation of power on this system, there by the suggesting a connection. The Congenerational production indicates higher effectiveness in the transformation of energy during primary production process due to the production of heat energy as well as the electrical energy from the primary power sources. In our country, as well as around the world, commonly used fuels are fossil fuels- coal, crude oil, and gas. As the demand for energy grows, those supplies are slowly running out. Not to mention that those fuels have a negative environmental impact. They are a source of carbon, which causes damage to the atmosphere and leads to global warming. Power plants which do not produce carbon are much safer for the environment, and much more productive. However, the residue of this energy is challenging to dispose of. Nuclear energy has common attributes with renewing the sources of energies that are extremely friendly to our environment. Nuclear power plants also produce enough energy and with the usage of Fourth generation reactors, they will be able to recycle the nuclear fuels. Today, more importance is put on renewing sources which are more gentle for the environment. In the near future, CEZ Company, the largest producer of electric energy is planning to use water energy. Water energy comes from water plants or dams. Other ecological forms of energy include geothermal and solar energies. These two types of energy are not as applicable for our geographical position. Geothermal energy is commonly used on islands where there is an abundance of natural hot springs. The most discussed source of energy is bioenergy. It uses natural wood sources, recycled wood products, and applies bioenergy as a main source for thermal power plants.
123

Posouzení možnosti provozu zdrojů v dané oblasti při nestandardních provozních stavech sítě VN / Evaluation of nonstandard operation possibilities of power sources in MV network

Čáslava, Jiří January 2012 (has links)
This Master's thesis deals with solution of nonstandard operation connection of E.ON's 22kV distribution network in given area, considering the possibilities of operating dispersed electric power sources currently available, as well as possible power sources connected to the distribution network in the future and its potential operation limitation. A part of this paper is a description of calculation methods used for network evaluation in steady state, with emphasis on linear calculations used by E-Vlivy program, in which the operational possibilities are simulated. Therefore, a description of this program is also included. Suggested operation possibilities correspond with E.ON's valid distribution network operation rules. The outcome of this paper will serve to E.ON's 22kV network's controllers as materials for network operating in nonstandard operation states.
124

Posouzení výhodnosti výstavby přečerpávací vodní elektrárny velkého výkonu v lokalitě Cukrová bouda, okres Šumperk / The assessment of advantages of construction of large hydroelectric power plants in the area of Cukrova bouda, district Sumperk

Knápek, Michal January 2012 (has links)
The subject matter of the master´s thesis is, in particular, an evaluation of the advantageousness of the construction of a pumped-storage hydroelectric power station in the vicinity of Cukrová Bouda. In the master´s thesis introduction the utilisation of pumped-storage hydroelectric power stations in providing reserve power generation to the operator of a power transmission system is discussed. The thesis then focuses on a technical design solution where two alternatives are drawn up for which the nominal parameters of individual designs for a pumped-storage hydroelectric power station are specified. The following part deals with the impact of the structure and the plant’s subsequent operation on the environment. A further key part is the determination of investment and subsequent operating costs and an evaluation of the plant according to economic pointers. The final part of the master´s thesis contains a SWOT analysis and an assumed programme of works for the plant’s preparation and actual construction. The conclusion contains an overall evaluation.
125

Analýza provozu trakční napájecí stanice / Hybrid AC/DC,AC/AC substation operation analysis

Lakomý, Marek January 2014 (has links)
The work analyzes the operation of hybrid substations. The first chapter provides an analysis of domestic traction systems and describes in detail specific station. The next chapter follows the first in a way in which obtained parameters are converted to parameters suitable for the simulation program and presents its results. The third chapter discusses the serial communication used in one switchgear and about voltage regulator that controls one high voltage field. The last chapter verifies the simulation results obtained from the second chapter with real measurement and direct comparison is also included.
126

Racionalizace konceptu připojení fotovoltaické elektrárny / Rationalization of the concept of photovoltaic power station connection

Svozil, Marek January 2015 (has links)
This masters thesis addresses the racionalization of the concept of photovoltaic power station connection. A way of compensation valuable components involvement standar- tizovaným inverter controlled by a microcontroller. Also includes the measurement of voltage and current using a microcontroller. The output voltage of the DC/DC con- verter is controlled by the variable duty cycle of the PWM signal generated by the microcontroller ATmega32.
127

Modernizace Jaderné elektrárny Dukovany / Modernization the Dukovany Nuclear Power Station

Kissler, Martin January 2015 (has links)
Thesis focuses on a detailed technical description of all important parts of secondary circuit in Dukovany power plant and its connection to other systems of power plant. In thesis are analyzed significant adjustments which have been made during the entire operation of power plant including in particular the actions associated with project called Utilization of project reserves of units EDU. In the main part of the thesis were carried out calculations of the power plant's power for states before and after the modernization and there is also analyzed the impact of individual changes on the whole power plant. These changes are with the entire secondary circuit drawn in the T-s diagram.
128

Nätanslutning av en framtida elväg : En kartläggning av anslutningsmöjligheter för E4an mellan Gävle och Stockholm / Grid connection of a future electric road

Ekström, Amelie, Wänlund, Jessica January 2021 (has links)
The transport sector accounts for a third of Sweden’s total greenhouse gas emissions where cars and heavy trucks dominate the use of fossil fuels. The Swedish government is now intensifying the work for an electrified transport sector where electric roads could be an important part. Electric roads enable heavy vehicles to charge their batteries while driving, which is expected to contribute to environmentally friendly and time-efficient freight transports. To implement electric roads, availability of electric power along the electric roads will be required. This study presents a plan for connecting an electric road to the electricity grid in the electricity network area of Vattenfall Eldistribution. From the results, the idea was to present general conclusions from the experiences of the study, that could contribute in further implementation of electric roads.  The road that has been selected for the study was the E4 between Gävle and Stockholm. A model for calculating the power demand along the electric road has been modeled and connection possibilities to transformer stations has been investigated. The analysis was based on three scenarios where different degrees of strengthening of the existing electricity network were assumed. In addition, a forecast for 2030 and a cost estimation for each scenario has been carried out. The result of the study indicates that for road sections close to larger cities, there are a larger number of connection options in comparison to rural areas. Furthermore, the designed solution in the study required strengthening of the electricity grid and the investment cost was 362 million Swedish crowns.
129

Nätanslutning av en framtida elväg : En kartläggning av anslutningsmöjligheter för E4an mellan Gävle och Stockholm / Grid connection of a future electric road

Wänlund, Jessica, Ekström, Amelie January 2021 (has links)
The transport sector accounts for a third of Sweden’s total greenhouse gas emissions where cars and heavy trucks dominate the use of fossil fuels. The Swedish government is now intensifying the work for an electrified transport sector where electric roads could be an important part. Electric roads enable heavy vehicles to charge their batteries while driving, which is expected to contribute to environmentally friendly and time-efficient freight transports. To implement electric roads, availability of electric power along the electric roads will be required. This study presents a plan for connecting an electric road to the electricity grid in the electricity network area of Vattenfall Eldistribution. From the results, the idea was to present general conclusions from the experiences of the study, that could contribute in further implementation of electric roads. The road that has been selected for the study was the E4 between Gävle and Stockholm. A model for calculating the power demand along the electric road has been modeled and connection possibilities to transformer stations has been investigated. The analysis was based on three scenarios where different degrees of strengthening of the existing electricity network were assumed. In addition, a forecast for 2030 and a cost estimation for each scenario has been carried out. The result of the study indicates that for road sections close to larger cities, there are a larger number of connection options in comparison to rural areas. Furthermore, the designed solution in the study required strengthening of the electricity grid and the investment cost was 362 million Swedish crowns.
130

Avledning av öringsmolt (<em>Salmo trutta</em>) från turbinintag / Diversion of trout smolts (<em>Salmo trutta)</em> from turbine intakes

Engqvist, Thérèse January 2009 (has links)
<p>Vattenkraftstationer, med dammar och turbiner, utgör hinder för nedströmsvandrande smolt. Syftet med denna studie var att undersöka turbindödligheten för öringsmolt (<em>Salmo trutta)</em> vid två kraftstationer, de befintliga ytlänsarnas avledningseffekt och om effekten kunde förstärkas genom mörkläggning i form av övertäckning av kraftkanalen med en presenning vid turbinintaget. Utöver detta var avsikten även att undersöka om det fanns något samband mellan smoltgrad och smoltens förmåga att förflytta sig mot havet. I Emån i Småland fångades 46 öringsmolt som radiomärktes och sattes ut vid två kraftstationer och pejlades dagligen i sex veckor. Det var en större dödlighet vid den övre stationen än vid den nedre. Ytlänsen vid den nedre stationen hade en klart avledande effekt, men inte ytlänsen vid den övre stationen. Samtliga smolt som valde passage via isutskovet, gjorde det när kraftkanalen vid turbinintaget var övertäckt med presenning (d.v.s. ljusintensiteten minskades kraftigt). Det gick inte att påvisa någon skillnad mellan låg och hög smoltgrad eller tidig och sen utsättning för fördröjning vid den ena kraftstationen, inte heller för förflyttning efter de två kraftstationerna.</p> / <p>Hydropower plants, with dams and turbines, form obstacles to smolts migrating downstream. The purpose of this study was to investigate turbine-induced mortality of brown trout (<em>Salmo trutta</em>) smolts at two power plants, guidance efficiency of existing diverters and whether the effect was enhanced by reducing light levels at the turbine intake by covering the power plant channel with an opaque tarpaulin. Furthermore, the aim was to investigate whether there was a relationship between smolt status and the smolts’ ability to move towards the sea. In the River Emån in Småland 46 trout smolts were caught, radio-tagged, released at two power plants and tracked daily for six weeks. There was a higher mortality at the upper power plant than at the lower one. The diverter at the lower power plant had a statistically significant guiding effect, but the diverter at the upper power plant did not. All of the smolts that chose passage through the trash gate did so when the power channel was covered with tarpaulin (i.e. light levels were greatly reduced). There was no evidence that smolt status or release date would affect passage times at the upper station, nor did smolt status affect swimming speeds downstream of the two power stations.</p> / Cost-Benefit Analysis of River Regulation

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