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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.
41

Vliv připojování disperzních zdrojů na DS 22 kV v dané oblasti a určení dopadů na provoz DS / Influence of Distributed Generation on Given Area of 22 kV Distribution Network

Samuel, Tomáš January 2010 (has links)
The Thesis deals with the current problem related to the connection of dispersive sources to the distribution network. The advantageous legislative support, however, gives a rapid rise to the sources of this kind. Current pricing philosophy favours in particular the growth of photovoltaic power plants. The introduction is aimed at the dispersive sources locating so as to give a comprehensive solution and better understanding of this issue. The equipments of this kind are located in accordance with legislation in force; however, it is necessary to formulate the possibilities of placing them from the view of rational use of the area with the aim of the public weal accordance of both public and private interests. Talking about connection of the new dispersive sources to the distribution network, it is important to mention the legislation, legal directives and regulations delimitating this kind of trade. This theme is the subject of another chapter of the work. Particular attention is paid to the regulation on conditions of connection to the distribution network. When connecting the sources to the distribution network the biggest technical problem from the view of electrical engineering is undesirable influence on the quality parameters (voltage) in this network. This is in particular the voltage change after connection, then, depending on the type of source, the emission of the current harmonic, sharp voltage change, etc. Considering current rise of the dispersive sources connected to the distribution network, more and more influence will appear in quantity parameters. For this reason there will be a lot of search for the methods of preventing from the negative influence on the network. From all of the above said reasons, the work is aimed at the operation analysis of the part of the distribution network, calculation of the network qualitative parameters and searching for the methods of negative influence rectification owing to switching processes of the distribution system. So as to determine the quantitative parameters we used the E-influence programme. Final paragraphs are devoted to the changes to come not only in legislation but, in general, in the approach of the distribution system operators not only to the ways of another connection of such sources but even the regulation of the dispersive sources already connected.
42

Vliv decentrálních zdrojů na provozování distribuční soustavy 110 kV E.ON / The impact of distributed generation on 110 kV distribution system E.ON

Hajdú, Lukáš January 2011 (has links)
This Master´s thesis deals with problematics related to the connection of new decentralized power sources into electrical power grid. Due to advantageous legislative support of these new, especially photovoltaic power sources, a massive amount of these sources have been connected into the power grid between years 2009 and 2010. For theoretical understanding of processes during a steady-state, the initial parts of this paper are focused on a procedure which solves steady-state on every power line mentioned. When we speak of decentralized power sources connection, it is necessary to mention the connected legislative. National distribution grid operators in collaboration with national regulatory commission have decided on a legislative document Rules of distribution grid operation, which puts a set of demands and requirements on applicants wishing to connect a new power source to the grid. The text of this thesis is focused mainly on demands required after the latest change in 1/2010. Practical part of this work deals with verification of new power source influence on a related power grid and meeting the legislatively required demands. The most important demands are voltage change due to new power source operation and its transfer to other voltage levels, higher harmonics injection, power output fluctuation and last, not least, changes in load flow directions. For reasons previously mentioned an analysis is made and possibilities of reducing or removing of these influences are introduced. To achieve these goals, two computer programs, Siemens Sinaut Spectrum and NetCalc are used.
43

Studie připojitelnosti výrobny / Study of Power Plant Connection to Power Network

Sýkora, Martin January 2011 (has links)
It is necessary to judge the influences of producers on the electric compounds while creating electrical energy or during the regulation of those existing. These analyses are sorted out by so called studies of connectivity. These calculations analyze the degree of connection of the producer and the standby unit during a break-down. The results of this report are several recommendations for creating such unit and succeeding steps leading to secure the stability and safety of the electric compound operation. The aim of this thesis is to discuss about software for PC solutions for static and dynamic network model, to draft power outlet into a network of generating high voltage, to complete a study of connectivity with respect to all the distortion factor, as increased voltage, inrush current at startup, flicker, harmonic currents, interference ripple, contribution to short-circuit current, reactive power control options, and demands for compensation.
44

Trh a obchodování s elektřinou z obnovitelných zdrojů v EU / Markets and Electricity Trading from Renewable Sources in EU

Pěcha, Jiří January 2011 (has links)
The submitted diploma thesis describes particular types of European energetic exchanges, focuses in depth on principles market in Czech Republic and studies the price development on spot and futures markets. The main idea of this work is to focus on renewable energy sources (RES) and their influence on energetic markets. At first, operational and reliability properties of RES are explained and then their development support is analyzed. Last chapters focus on how the power grid is impacted by RES that are hardly predictable source with local production characteristic. There are also outlined problems originating from irregular production that are linked to a surplus of electric energy, but also on energy shortage caused by bad weather. These problems influence international commerce and reduce the capacity of cross-border profiles.
45

Stav fotovoltaiky v České republice / State of photovoltaic in the Czech Republic

Lukášek, Kamil January 2015 (has links)
Photovoltaic in the Czech Republic has gone through significant development during last few years. The thesis describes physical principle of converting solar energy into electrical energy using photovoltaic cells. Photovoltaic power plant is a set of technologic components connected together to utilize solar energy and convert it into electric energy that could be distributed to electric power network. Review of the photovoltaic development in the Czech Republic and the list of the biggest operational photovoltaic power plants present important data for assessment of the current status of photovoltaic technology in the Czech Republic. Chapter operations and maintenance of photovoltaic power plants summarizes the most common causes of failures and presents diagnostic tools for service requests. Due to legislative changes, hybrid photovoltaic power plants construction has been prioritized as it is economically more efficient now. Construction of new hybrid photovoltaic power plant was assessed analytically using SWOT analysis that evaluates strong and weak sides of the projects in comparison with opportunities and threats of construction. After evaluation of obtained data the next steps of the hybrid photovoltaic power plant’s construction plan are proposed. The first part of hybrid photovoltaic power plant design contains PVGIS program's data evaluation, which provides sunlight intensity information for specified area. Obtained data were used in the second part of the design to determine proper components selection for family house hybrid photovoltaic power plant. Finally the economic view of the design and return of investments were assessed.
46

Koncept rychlonabíjecí stanice pro elektromobily s akumulací / Concept of Fast Charging Station with Accumulation for Electric Vehicles

Miškovský, Ján January 2017 (has links)
Main purpose of the thesis is the creation of a concept a fast-charging station associated with accumulation that uses renewable source. The introduction of the thesis describes a standard that specifies the charge of electric vehicles using direct and alternating current as well. It depicts an overview of using charging connectors. The first part also deals with overview of the technology of renewable sources and exploitation energy storage system for charging station. The second part introduces the theoretical basement for mathematical model of the charging station in Matlab/Simulink. The function of model station is verified by a physical laboratory model. For options verification of the connection station to the distribution net is created simulation of voltage losses in Matlab/Simulink. The thesis shows four 24 hours’ scenarios that have been simulated. According to the assumptions of simulation, the technology of station and connecting component is suggested. Next is the designed energy and financial analysis of the project charging station until 2030.
47

Polyfunkční dům v Ledči nad Sázavou / Mixed-use Building in Ledeč nad Sázavou

Nevím, Tomáš January 2022 (has links)
The master thesis designs a mixed-use building in Ledeč nad Sázavou. The thesis consists of three parts. First part presents the project documentation of architectural-construction. Second part proposes the technical equipment of the building. Third part is assessment of the designed building by methodology for multicriteria evaluation of buildings SBToolCZ. The building is located in undeveloped and slightly sloping land. The building has three above-ground floors. There are three different operations in the building, which are a café and an electrical shop and an office part. There is a café, an electrical shop, technical and storage facilities on the first floor. The second and third floor is an office part and company apartment. Structurally, the building is solved by a two-wax load bearing system. The building is founded on footing and foundation slab. Load bearing vertical elements are walls, columns and posts. Externall wall is designed from ceramics block with and mineral insulation. Horizontal load-bearing structures are designed as cast-in-place reinforced slabs. The building has a flat roof. In the building is air condition and cooling system and heating. Part of electricity demand is covered by photovoltaics on the roof. All drawings and visualization are designes in software ArchiCAD.
48

Fotovoltaické dobíjecí regulátory v ostrovních systémech / Solar charge controllers for off-grid systems

KRČKA, Pavel January 2013 (has links)
This diploma thesis deals with photovoltaic rechargable regulators used in isolated, or off-grid photovoltaic systems. First, basic types of off-grid installations, including their functions and applications in practice are described. Then, possibilities of electric energy accumulation in photovoltaic systems are mentioned, considering actual, accesible technologies. Matters of electric energy accumulation in leaden accumulators are examined in detail. Main part of the diploma thesis is about electronic designs of photovoltaic, also called solar, rechargable regulators. These are the main connecting part between photovoltaic panels, accumulator, but also often connected charge, which is appliance. Individual electronic regulators concepts are described narrowly, then compared and evaluated in thesis´ conclusion.
49

Koncept nabíjecí stanice s možností off-grid provozu pro elektrokola / Concept of Charging Stations with off-grid Operation for Electric Bicycles

Leitman, Valentín January 2017 (has links)
This thesis deals with charging stations for electric bicycles powered by renewable energy. The aim of this work is to make a proposal for the hybrid charging stations for electric bicycles, which will work independently and, if necessary, will be backed up by a network. In this thesis is entered theoretical information on the issue of electric bicycles, the batteries, charging stations, the connectors of chargers, and photovoltaic systems. The practical part of this thesis is the basic design of the charging station and its design of the mathematical model of the individual parts in Simulink program, which are linked to the actual design of the charging station. In conclusion, this thesis deals with energy and economic analysis of the proposed system, therein included various methods of assessing investment recommendations of appropriate processing methods and overall assessment of the subject.
50

Začleňování fotovoltaických elektráren do elektrizační soustavy / Integration of Photovoltaic Power Plants in the Electricity System

Michl, Pavel January 2010 (has links)
The thesis discuses an integration of photovoltaic power stations to electric network. The first part describes connecting conditions of small sources to distribution system, including administrative requirements, feasibility study, and requirements to the energy meters, measuring, control devices, switching devices and protection. The second part is aimed to describe problems of the photovoltaic system. Solar radiation generating and reducing of its intensity incident upon the earth surface are described in this part. The quantum of produced electric power depends on climatic conditions in the fixed area, seasons, etc. This work also discusses the types of photovoltaic cells and their actual efficiency. Inverters are further important components of the photovoltaic system. The parameters of the inverters have a great influence on the total actual efficiency of the photovoltaic system. Different methods of the photovoltaic panels’ connection with the inverters and their advantages and disadvantages are also mentioned. The supporting structure of the photovoltaic panels and eventually transformer are further important components of photovoltaic system. The work also analyze the methods of connection of the photovoltaic power station to distributive low voltage and medium voltage network, electric energy accumulation and possibilities of the sale of produced electric energy. The large number of the connected photovoltaic power stations has negative influences to electric network. The third part contains the design of a photovoltaic power plant with a capacity of 516,24 kWp on the scoped area in southern Bohemia. The project documentation for the location where the power plant is designed is also made. It contains the design of photovoltaic panels, the design of the inverters to get an optimal power load. This part also contains a calculation of the photovoltaic system losses and the design of transformer and the cable junction calculation of the distributive system. The feasibility study of the power plant connected to distributive system is also conducted. Its delivery rate will be connected to the distribution point Řípov (110/22 kV). The calculation results show us that this photovoltaic power plant can be linked to the distribution system. The final part of this paper contains an economic estimate of the photovoltaic power plant operating and the calculation of the return. An Economic return is influenced by the wide range of values that affect the total return rate. The calculation of an operating economy is made for several variants. The return rate in refer to contemporary redemption price for 2010 with no consideration for a bank loan is 7 years. If we consider the bank loan it would be 12 years. The penetrative reduction of the redemption price is expected for 2011. Calculation works with the decline of 30 %. It would extend the rate of return to 11 years without a bank loan or to 22 years with the bank loan. The bank loan is considered to cover 80 % of the investment.

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