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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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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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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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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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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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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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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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