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Calculation and technical solutions earthing system of transformer substation 110/22 kV
Mašek, Jakub ; Dušek, Igor (referee) ; Bátora, Branislav (advisor)
Master's thesis deals with principles of design of earthing of a substation 110/22 kV. Specific requirements for safety have to be fulfilled when designing power installations exceeding 1kV. The aim of this paper is to design a new earthing system for reconstructed substation 110/22kV considering valid standards. Reconstruction of a property is always more or less complicated by new orders and regulations for construction. Earthing is a part of all electric equipment, therefore it is essential for the design engineer to consider a broad spectrum of requirements, even those seemingly not related to this subject, from legislative requirements to the study of reactions of a human body to electric current. The theoretical part of this work examines different approaches to earthing system's design, and analyzes the origins and earthing standards throughout history. The correctness in consideration of effects of the environment is an often neglected factor. Defining of all types of effects of the environment is a broad field, therefore this paper only summarizes the main principles. The practical part of this paper deals with the basic design of substation's earthing system and it's verification in respect of touch voltage and step voltage according to the Czech national standard ČSN 33 3201 (Power installations exceeding 1kV a.c.) and of company's energetics' standard PNE 33 0000-1 ed.4 (Protection against electric shock in distribution network and transmission system) required by the substation's distributor. This paper later quotes and takes into consideration the requirements of other standards, more or less related to listed documents, creating an interconnected body for design and testing the earthing system.
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The measurements of earthing systems and the role of electrical soil resistivity
Capyk, Jan ; Jurák, Viktor (referee) ; Vyčítal, Václav (advisor)
The theoretical part of the thesis is focused on explaining the concept of soil resistivity, applicable methods of its measurement, comparison of two methods used to measure the resistance of the earth electrode and a description of the measuring device Metro PU 193 used for the practical part of the thesis. In the practical part, the reader is acquainted with the results of measuring soil resistivity and earth resistance in the field, with their evaluation with respect to various influencing factors and with designs of earth conductors for high voltage poles for which soil resistivity was measured. The thesis contains plotted graphs of various dependencies according to the results of measured values and compares them with theoretical assumptions.
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Evaluation of MV/LV network earthing systems
Sítař, Martin ; Topolánek, David (referee) ; Kopička, Marek (advisor)
This master's thesis deals with the measurement of grounding systems in HV/LV distribution networks, which includes grounding system of distribution substation and transmission lines. Explores the issue and principles for the measurement of parameters, which are important for the protection of persons and animals in order not to touch exposed conductive part accidentally, protection of electrical machines and equipment against high fault current and dangerous surges while the correct function of the connected electrical equipment is maintained. These parameters include earth potential rise, ground resistance, soil resistivity, touch voltage, step voltage and transferred potential to the LV network. The aim of this work is the preparation, analysis and subsequent evaluation for the real measurement in practice. These earthing-system measurements were carried out at the distribution station and the concrete pole with a section disconnector. Then a numerical model of the grounding system of concrete pole was created in ANSYS. Subsequent evaluation of the results as numerical terms (comparison measurements and simulated results) and evaluation in terms of analytical (measurement results compliance with the standard) including the numerical model of the earthing system is solved in the practical part of the master's thesis.
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Single railway electrification system design
Svoboda, Ondřej ; Radil, Lukáš (referee) ; Pelc, Jiří (referee) ; Drápela, Jiří (advisor)
The main topic of the thesis is the design of single-track electrification of a direct current system of 3 kV and an alternating current system of 5 kV 50 Hz and then economically evaluate it over a period of 30 years. The work deals with basic traction systems and also deals with the calculation of main parameters of electric trains. The thesis describes in detail the procedure for the design of the electrification of the track and a partial introduction to the simulation programs that were used for energy calculations.
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Protective measure - automatic disconnection of suply
Leitner, David ; Vaněk, Jaromír (referee) ; Valenta, Jiří (advisor)
The aim of this thesis is to explain the principle of automatic disconnection of supply, which is one of the basic protective measures for security assurance in electric installations of low voltage according to the new issue of Czech Technical Standard (ČSN 33 2000-4-41 ed. 2). Furthermore, the relevant clauses of the Czech Technical Standard in the new and previous issues are compared, with focus on the problem of automatic disconnection of supply in basic types of distribution networks. In agreement with theoretical conclusions, a project of electric energy supply system is proposed in the practical part of the thesis. Special attention is paid to showing the methods of modeling and verification of conditions for automatic disconnection of supply, with using control calculations in the SICHR program. Finally, the fulfillment of the conditions for automatic disconnection of supply is verified by revising the electrical supply system.
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Project of Earthing System in 110/22 kV Transfornmation Station
Pavlík, Ludvík ; Procházka, Aleš (referee) ; Orságová, Jaroslava (advisor)
This Thesis is concerned with the concept of grounding of 110/22 kV transformer station. The aim of the Thesis is to create a ground network for grounding a specified outdoor substation. This 110 kV outdoor substation is formed according to H-scheme and encircles a wide area. In additon to this, an earth potential has to be distributed as equally as possible within the whole area of the substation. The most convenient alternative from the point of view of effective grounding and distribution of potential is a grid network. Therefore, the grid network is the means of grounding which I have chosen as a solution for this issue. In this solution, flat conductor network cables are used to cover the whole substation, with ground rods placed at the points of intersection. Parts of appliance can be then connected to this existing network, thus creating several parallel channels which provide grounding with low resistance. The network is made of common steel zinc-coated stip, size 30 x 4 mm. When proposing a concept of grounding and adjustment of ground electrodes, we have to take account of grounding requirements, stated according to ČSN standards. The proposed earthing system was created in appropriate size in order to meet all these grounding requirements. These requirements are also mentioned and described in a theoretical part of the Thesis. Second part of the Thesis consists of proposed concept of the grounding itself, together with calculated parameters. The grounding has to be carried out according to both safety regulations and electrical appliance requirements. The issue of grounding substations of power system is resolved by the ČSN standards 33 3201 (“Elektrické instalace nad AC 1kV”), 33 2000-4-41 (“Elektrická zařízení – Ochrana před úrazem elektrickým proudem”) and 33 2000-5-54 (“Elektrická zařízení – Výběr a stavba elektrických zařízení – Uzemnění a ochranné vodiče”) and by the PNE company standards 33 0000-4 (“Příklady výpočtů uzemňovacích soustav v distribuční a přenosové soustavě dodavatele elektřiny”) and 33 0000-1 (“Ochrana před úrazem elektrickým proudem v distribuční soustavě dodavatele elektřiny”). These standards apply to creating a concept of grounding and grounding of new, reconstructed or expanded electrical substations of power system.
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Creation of a laboratory model of the earth system
Moliš, Martin ; Vyčítal, Václav (referee) ; Topolánek, David (advisor)
This work deals with designing of grounding system model. This model might be used for potential distribution, step and touch voltage measuring, depending on particular grounding system. Moreover measuring transferred potential into another grounding system and the influence of foreign grounding system’s presence on the overall earth resistance. The aim of this work is to create a simulation on the model of whole system’s behavior during a fault on the power line. This model also might be used for laboratory classes.
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Problems of measurement and evaluation of earth resistance
Šindelář, Petr ; Janda, Marcel (referee) ; Veselka, František (advisor)
This work deals with the measurement of earth resistance, definition, substances causing earth conductivity, basic norms for carrying out grounding revisions and effect of earth resistance on securing and protection element. In the introduction there is theoretical analyzing of grounding issue and principles for the measurement of parameters, which are important for the protection of persons and animals in order not to touch exposed conductive part accidentally, protection of equipment against high fault current and dangerous surges while the correct function of the connected electrical equipment. In the next part there are described methods of earth resistance and soil resistivity measuring. The practical part of the work summarizes the results of practical measurements in individual places with different measuring device.
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Measurement of grounding system HV/LV and touch voltages around distribution transformer station
Sítař, Martin ; Topolánek, David (referee) ; Kopička, Marek (advisor)
This work deals with the measurement of earth resistance of grounding system and verification of touch voltages around outlying, suburban and urban distribution transformer stations and HV masts. When designing the grounding systems certain specific requirements for performance and safety are required. The aim is to practically verify earthing resistances at selected distribution transformer stations and HV masts of power line. Another objective of this work is assessment of the maximum possible touch voltages during fault conditions in these selected HV systems and to produce technical report which includes test results and final evaluation in compliance with valid standards.
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The measurements of earthing systems and the role of electrical soil resistivity
Capyk, Jan ; Jurák, Viktor (referee) ; Vyčítal, Václav (advisor)
The theoretical part of the thesis is focused on explaining the concept of soil resistivity, applicable methods of its measurement, comparison of two methods used to measure the resistance of the earth electrode and a description of the measuring device Metro PU 193 used for the practical part of the thesis. In the practical part, the reader is acquainted with the results of measuring soil resistivity and earth resistance in the field, with their evaluation with respect to various influencing factors and with designs of earth conductors for high voltage poles for which soil resistivity was measured. The thesis contains plotted graphs of various dependencies according to the results of measured values and compares them with theoretical assumptions.
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