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The quality of electric energy in a low voltage public supply networks
Macoszek, Pavel ; Šlezingr, Jan (referee) ; Bok, Jaromír (advisor)
This thesis contains four main chapters, which describe qualitative parameters of supply voltage and measurement and analysis received information. The theoretical part consists of three chapters. Characteristics of low voltage are described in the first chapter. Next chapter describes disturbing events, which have influence on quality supply voltage, reasons for their occurrence spreading in network, eventually arrangement leading to the disappearance of disturbing events on other electric appliances in network. Last theoretical chapter describes measuring instruments of supply voltage. The purpose of these theoretical parts is to introduce the reader into supply voltage quality issues and can be used for preparation of measurement and evaluation of acquired data under norm ČSN EN 50160 (Voltage characteristic of electricity supplied by public distribution systems). An analysis of real network is the last part of this thesis. There is applied acquired knowledge with the aim of analysis of real states of qualitative parameters of supply voltage in network.
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Design of protection against lightning and data distributions photovoltaic plant
Manduch, Viliam ; Bátora, Branislav (referee) ; Radil, Lukáš (advisor)
This thesis deals with the problems associated with the lightning. It deals with the stablishment, descriptions and analyzes of risk the living organisms and objects are facing. The work focuses on the description and implementation of protection against these adverse effects. Its objective is to devise a system for lightning protection for chosen PV power plant to meet the requirements of standard of EN 62305. The work is also the analysis of shadow effects in the collecting system for PV power systems.
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Design of overvoltage protections according to CSN EN 62 305
Pochop, Zbyněk ; Paar, Martin (referee) ; Bátora, Branislav (advisor)
This Bachelor's thesis deals with the procedure in designing overvoltage protections for an ordinary house according to a new set of standards CSN EN 62305. The work consists of three main parts. The first part deals with the method of risk management according to standard CSN EN 62305-2. Besides a theoretical introduction is made a risk analysis also numerically. Result of risk analysis has implications for the way forward surge protection design for the entire building. The second part deals with the external surge protection. In the second part of the text are suggestions down lead systems and primarily air terminals. Check over is subsequently verified by the methods of the protective angle method and the rolling ball. The study also addressed the issue of TV antennae on the roof near the air-termination network. The third part of this thesis deals with internal overvoltage protection, which mainly concerns the design and location of surge arresters and lightning arrester.
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Barriers of renewable sources expansion in the Czech Republic
Lukášek, Kamil ; Březina, Ladislav (referee) ; Mastný, Petr (advisor)
Currently, there is no publication that concerns the renewable resources comprehensively in the Czech Republic. This publication defines the renewable resources in general meaning. Whereas the physical and legal definitions of the renewable resources are different, text explains the principle of production of electricity according to the legal definition. When the renewable resources are being constructed, it's important to achieve the optimal operating conditions. To achieve these conditions, it's necessary to locate the renewable resource in the Czech Republic. The operations of renewable resources are partly financed by the country, in order to be more interesting for the investors. Further on, the conditions of connection to electrical distribution system are defined. The impact of renewable resources on electrical distribution system. Finally the conception of renewable electrical energy resource for region of East Bohemia is designed.
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High Speed Transients Modelling
Bukvišová, Zuzana ; Topolánek, David (referee) ; Orságová, Jaroslava (advisor)
This thesis deals with the high speed transient modelling in the electrical networks. The introduction of this work discusses mathematical models of the individual devices used in the system and focuses on the line representation. It also contains a more detailed description of Bergeron and frequency dependent line model. The objective of this thesis is to design a network model using ATP-EMTP simulation program. In this model, the switching overvoltage caused by shunt reactor switching and lightning overvoltage are simulated. The thesis thoroughly describes the settings of the components used in the model of analysed network and in conclusion evaluates obtained simulation results in a relation to the insulation coordination.
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Surge arresters, their construction and use in power system
Novický, Marek ; Pelikán, Luděk (referee) ; Orságová, Jaroslava (advisor)
The bachelor thesis deals with the means used to protect the equipment from the effects of overvoltage. The first of the thesis outlines basic information regarding the used overvoltage protections in the distribution system. The thesis also features the practical part outlining measurements carried out on the surge arrester. The last chapter deals with the dimensioning of the surge arrester in the high voltage distribution system.
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Analysis of Ferroresonance Overvoltage in Electrical Net
Bátora, Branislav ; Eleschová,, Žaneta (referee) ; Krejčí, Petr (referee) ; Toman, Petr (advisor)
This thesis deals with the ferroresonance phenomenon and ferroresonance overvoltage in electric networks. That’s why the introduction part explains the theoretical basis of ferroresonance and its consequences in the power system. The work then focuses on the power system as a non-linear dynamic system and describes various analytical methods for solving these systems. These methods are further applied to diagnose specific systems. There are a number of various power system configurations susceptible to ferroresonance. The most frequent one is theoretically analyzed in this thesis and a number of recommendations are offered for reducing the ferroresonance phenomenon. The thesis further deals with the selection of suitable software for this computationally chal-lenging task. A number of different tools are considered and efficiently reduced to Matlab Sim-ulink and PSCAD software. Matlab Simulink and its SimPowerSystem Toolbox are used to ana-lyze the effect of hysteresis of the magnetic core of the transformer on the emergence and course of the ferroresonance phenomenon. Using PSCAD, various configurations of the power systems are compared in terms of possible emergence and course of ferroresonance and also to find the limiting conditions that increase the probability of this phenomenon. The possibility of using arti-ficial neural networks for ferroresonance diagnosis is also mentioned in this thesis. The final part provides a number of recommendations for design and operation of both new and existing power systems.
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The quality of electric energy in a low voltage public supply networks
Vývoda, Marek ; Pithart, Jan (referee) ; Bok, Jaromír (advisor)
This thesis deals with description of qualitative parameters of supply voltage as well as measurement and data evaluation issues. Theoretical part of thesis describes basic characteristics of low voltage and limits based on standard specification. Next chapter deals with specification of measurement devices used for supply voltage quality measurement. The purpose of these theoretical parts is to introduce reader into supply voltage quality issues and can be used for preparation of measurement and acquired data evaluation under norm ČSN EN 50160 (Voltage characteristic of electricity supplied by public distribution systems). An analysis of real network is the last part of this thesis, in which application of acquired knowledge on assigment of real states of qualitative parameters of supply voltage in network.
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Fast Transient Phenomena in High Voltage
Vala, Martin ; Dohnal, Petr (referee) ; Krbal, Michal (advisor)
This work deals with research and description of the fast transients in high voltage technics. First part deals with division of fast transients and description of an impulse wave properties. Second part is focused on atmospheric overvoltage description and on direct and indirect lightning surge protection methods. Next, there are described the main characteristics and division of the surge protection devices in the work. In the next part, there are introduced some sort of high voltage generators, used for meassurement of impulse wave in a transmission line. In the last part there is stated an analysis of practical measurement of impulse weaves and surge arresters by using a Marx generator.
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