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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.
251

Návrh rozvoje a řešení konfigurace sítě 22 kV / Distribution Network Development and Configuration

Pospíšil, Petr January 2010 (has links)
The theme of this master‘s thesis is distribution network development and configuration in the part of Brno – Trnitá. There is expected to be investments there in the next few years. The thesis consists of two parts. For better understanding of this problem, the first theoretical part concerns with the description of electrical network (subdivision in accordance with voltage levels, conductor types, network types and other electrical network parts), solution of grid’s steady state (as a linear task and also non-linear task, elimination of the balancing node, the iterative method) and Brno distribution network characteristics. The second part concerns with distribution network development and configuration depending on anticipated load development in Trnitá. The result is proposal for transformer station construction Opuštěná fitted with three transformers of nominal output SN = 40 MVA and network configuration change required both for providing new consumption supply as well as sustaining current one.
252

Návrh rozvoje distribuční sítě 22 kV E.ON v zadané oblasti / Design of the expansion of 22kV distribution network in a specific area

Řehoř, Jiří January 2012 (has links)
The aim of this work is the reconstruction and development of the distribution network of DS to ensure electricity supply in the required quality to existing customers and new customers connecting to the planned industrial zone Šlapanice. The first part deals with the inclusion of a distribution network in power system, its distribution and composition. Subsequently, the work deals with the description of the management of distribution networks, cable and outdoor leadership and their parameters. It also contains guidelines for the design of high voltage networks. The end of the first part is devoted to calculating the steady operation of the network. In the second part, the proposed project using the PAS DAISY Off-line v 4.00 Bizon. Based on the available evidence is developed steady state operation. We found that lines are overloaded and need to be strengthened with regard to the development of industrial zones and adjusting the network to ensure safe and reliable operation. The conclusion focuses on the economic evaluation of proposed alternatives.
253

Návrh rekonstrukce distribuční sítě 0,4 kV E.ON v zadané oblasti / Proposal of the reconstruction of 0,4 kV distribution network in a specific area

Fojtík, Martin January 2012 (has links)
This Master’s thesis deals with the problem of distribution electrical network with a focus on solving the steady operation of the electrical distribution network for E.ON Brno - Lisen. The calculation is made by using BIZON PAS Off-Line. The first part of thesis is specialized on the distribution of individual LV and MV networks.The second part of thesis is specialized on the general calculation of the steady operation distribution network and describe criteria for the design and evaluation of this network. In the practical part is calculate existing network in selected area in which is located 53 distribution transformers. In the final part is evaluate the status of existing network and perform design optimization and assessment of this network.
254

Vyvedení výkonu z rozvodny 110/22 kV Moravany u Brna / Feeding power out of 110/22 kV Moravany u Brna substation

Chromík, Aleš January 2013 (has links)
The aim of this Master’s thesis is the design and reconstruction of the high voltage distribution network for the company E. ON with focus on calculation of the stabilized operation and on the planning of new cable taps from the transformer substation Moravany u Brna. The first part of the theoretical analysis of the work deals with the inclusion of the distribution network into the power system and with principles of development and construction of high voltage networks. The second part includes a general calculation of stabilized operation of the power distribution network and a familiarization with the program PAS Off - Line Bison 4.0. The practical part of the thesis is focused on the calculation of the stabilized operation at the current state of transformer substation Moravany u Brna using the PAS Off - Line Bizon 4.0 V programme. This part also contains the design of six new cable lines which are needed to strengthen the power distribution in the southern part of the city Brno. The closing part of this chapter constitutes of a outdoor and indoor cable line renovation. These cables are connected to the transformer substation Moravany u Brna and a calculation of stabilized operation is also included in this part.
255

Systémy PLC ovládané dotekovým panelem pro řízení VN zařízení / Touch panel controlled PLC systems for HV device control

Vlk, Jáchym January 2014 (has links)
The master thesis describes communication of PLC and touchscreen with purpose of high voltage control. The general information and framework are included. The thesis describes part of IVEP corporation development. Due to the beginning of a long-term development it is premature to come into conclusions within this master thesis. The first chapter deals with PLC and other components. The second chapter consists of matters about high voltage devices. The following chapter describes the programme part. The fourth and concluding chapter deals with the realization of the communication itself. A brief evaluation with prospects for the future is included in the conclusion.
256

Měření kapacity vysokonapěťových přechodů PN / Capacitance measurement of high-voltage PN junctions

Derishev, Anton January 2015 (has links)
The work deals with the capacitance measurement of high-voltage PN junctions. The work is divided into theoretical and practical parts. The theoretical part presents insight into the fundamental properties of PN junctions and methods for measuring of the capacitance of PN junctions, primarily by C-V measurement. In the practical part, several kinds of measuring circuits are introduced and a suitable method of measurement is found. The calculations of basic parameters - the width of the base and resistivity are presented and discussed. The results were compared with the values obtained by calculation from the technological parameters of the junction.
257

Analýza teplotního pole vysokonapěťového rozvaděče / High Voltage Switchgear Thermal Distribution Analysis

Bílek, Tomáš January 2015 (has links)
Cílem této práce je analýza teplotního pole vysokonapěťového rozvaděče. Tato analýza je založena na kombinaci experimentálního měření a CFD simulace proudění vzduchu v prostoru rozvaděče. Na základě výsledků pro referenční geometrii jsou předloženy návrhy na úpravu topologie rozvaděče, které mají za cíl snížení teploty kritických komponent rozvaděče během jeho provozu. Druhá část práce je spojena s problematikou oteplení plošných spojů, jakožto hlavních zdrojů tepla v prostoru rozvaděče. Pro popis závislosti oteplení plošného spoje na jeho charakteru byla použita statistická metoda design experimentu. Výsledky z experimentálního měření jsou podpořeny konečně prvkovým modelem kontaktu spoje.
258

Selektivplan för högspänningsnät i södra Sverige : 130-, 20-, 10 kV / Selectivity plan for a high voltage power grid in southern Sweden : 130-, 20, 10 kV

Hansen, Simon, Karlsson, Fredrik January 2020 (has links)
I denna rapport utfördes en selektivplan på uppdrag av Kraftkällan Konsult för ett elnätsbolag i södra Sverige. Det visades att elnätet hade selektiva problem i samtliga stationer mellan reläskydden. Problemen har uppstått då karakteristiken i elnätet ändrats i samband med ombyggnationer. För att lösa problemen simulerades en modell av elnätet i PowerTools för att ta reda på kortslutningsströmmarna och nya selektivkurvor ritades efter dessa. Rekommendationer för högspänningssäkringar i nätstationer har också gjorts baserat på de nya kortslutningsströmmarna.
259

Analys av fältfördelning i kabelavslut av linjära och icke linjära material : Analysis of the field distribution in cable termination by linear and nonlinear material

Gabrail, Philip, Samuelsson, Sam January 2016 (has links)
I nuläget används XLPE högspänningskablar vid överföring och distribution av elkraft och har en viktig roll i elsystemet. Kraftöverföring som sker över långa sträckor kopplas vidare från en punkt till en annan och sker med hjälp av kabelavslutningar. Dessa kabelavslutningar har en del sårbarheter ”felfunktion i kabelavslut” som påverkar hela elkraftsystemet. En analys och simulering av fältfördelning i kabelavslut genomfördes genom en teoretisk-respektive praktisk del i rapporten. Den teoretiska delen av rapporten genomfördes med hjälp av FEM programmet Comsol Multiphysics. Resultaten visade att den högsta fältkoncentrationen uppstår vid isolationen av kabeln och orsakade felfunktion och sårbarheter. Vid det linjära fallet för den elektriska delen resulterade en hög permittivitet till att potentialen och det elektriska fältet minskades vilket var densamma med låg konduktivitet. För det olinjära materialet ändrade sig konduktiviteten med elektriska fältet och tiden. Temperaturen vid det linjära fallet visade att vid en hög temperatur blev materialet mer ledande och gav ett högt elektriskt fält i halvledaren. I det olinjära fallet minskades materialets ledande. Detta kunde regleras med olika tröskelvärde (Eb) vilket inte kan i det linjära fallet. Den praktiska delen genomfördes i E.ON:s laboratorium för olika typer av kabelavslutningar som testades med 33 kV. Vissa av de provade kabelavslutningarna användes för  provningssyfte och andra plockades ur drift på grund av felfunktion i kabeln. Ett försök för att kontrollera fältkoncentrationen genomfördes i laboratorium och resulterade till en reducerad fältfördelning i kabelavslutning. Resultatet av den praktiska delen visade hur fältkoncentrationen fördelades i kabelavslutning och att fältfördelning ledde till sammanbrott i kabeln. / Nowadays XLPE high voltage cables are used in transmission and distribution of electrical power and has an important role in the electrical system. Power transmission that occurs over long distances is diverted from one point to another and is done with the help of cable terminations. These cable terminations have some vulnerabilities that affect the entire power system. The theoretical part of the report was carried out with the help of FEM software Comsol Multiphysics. Results showed that the highest field concentration occurs at the insulation of the cable and caused malfunction and vulnerabilities. In the linear case for the electrical part resulted a high permittivity that the potential and the electric field was reduced, which showed the same result for low conductivity. For the nonlinear material the conductivity changes with the electric field and time. The temperature of the linear case showed that at high temperatures the material became more conductive. In the nonlinear case the conductive material was reduced. This could be controlled with different threshold value (Eb) which cannot in the linear case. The practical part was done in E.ON:s laboratory for different type of cable terminations that were tested with 33kV. Some of the tested cable terminations were used for testing purposes and was picked out of operation because of a malfunction in the cable. An attempt to control field concentration was carried out in the laboratory and resulted to a reduced field  istribution in the cable termination. The result of the practical part showed how the field concentration was distributed in the cable termination and that the field distribution led to the collapse of the cable. / <p>QC 20160718</p>
260

Design of power supply system in DC electrified transit railways - Influence of the high voltage network / Dimensionering av likspänningsbanmatningssystem – Inverkan av högspänningsnätet

Seimbille, Denis January 2014 (has links)
Urban rail systems such as subways and trams transport millions of people every day, oering a high level of service. Most of these systems are fed by direct current (DC). The design of the power supply network of DC electried transit railways is of great importance and requires the use of simulation models. The power supply network is composed of a high voltage network (fed with AC) linked to a traction network (fed with DC) by traction substations. Many simulation models ignore the high voltage network in the design process whereas it has a signicant inuence on the results. A Newton-Raphson algorithm is implemented to solve the AC load ow in the high voltage network, and coupled to the existing simulation software Symphonie. Three dierent high voltage network architectures are simulated, and the simulation results are analyzed. The results show that the voltage drop at the AC side of traction substations and the load sharing between them varies signicantly from one architecture to another. In particular, when several traction substations are connected to the same high voltage loop, voltage drops can be signicant for some traction substations. In conclusion, the design of the power supply network of DC electried transit railways requires the simulation of the high voltage network when several substations are connected to the same high voltage loop. / Publika sparburna transportsystem sasom tunnelbanor och lokalbanor transporterar miljontals manniskor varje dag. De esta korta linjer matas med likstrom. Utformningen av stromforsorjningen till dessa system ar avgorande for ett val fungerande , och forutsatter anvandningen av olika matematiska modeller. Detta natverk bestar av ett vaxelstroms hogspanningsnat som omformas till likstrom i era banmatningsstationer langs banan. Dessa matematiska modeller ignorerar dock ofta hogspanningsdelen i modelleringen, varfor resultatet ibland kan bli missvisande. I detta arbete har en belastningsfordelningsalgoritm baserad pa Newton-Raphsons metod implementerats for att skapa en battre modellering av hsgspanningsdelen i den bentliga programvaran Symphonie. Tre olika hogspanningsstrukturer har bearbetats och resultatet visar att spanningsfall och belastningsf ordelning varierar mellan de olika strukturerna. Speciellt nar era transformatorstationer ar kopplade till samma hogspanningssystem, kan spanningsfall vara patagligt for vissa transformatorstationer. Sammanfattningsvis maste utformningen av hogspanningsystemet till likstromsforsorjda jarnvagar utformas med hjalp av anpassade matematiska modeller som tar hansyn till placering av transformatorstationer liksom hogspanningsnatets kapacitet.

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