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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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SAIDI and SAIFI Calculation for a Low Voltage Distribution Networks in Mesh Configuration
Dohnal, Josef ; Souček, Jan (referee) ; Paar, Martin (advisor)
This diploma thesis aims to briefly interpret problems relating to continuity of distribution of electrical energy in a distribution network of low voltage. It also mentions methods of calculation of a distribution system´s reliability which are the most used in practice. Next, there is a chapter dedicated to how distribution networks are projected and operated in the Czech Republic and in the United Kingdom. Based on experiences with meshed networks operation this thesis designs protection of meshed distribution network of low voltage. In the end, a non-sequential method of Monte Carlo is used to calculate System Average Interruption Index (SAIDI) and System Average Interruption Frequency index (SAIFI).
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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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Power Losses Calculation Depending on Distribution Network Configuration
Domes, František ; Souček, Jan (referee) ; Paar, Martin (advisor)
This master‘s thesis deals with the calculation of losses depending on the configuration of the distribution network. The first part focuses on the general theory regarding some used calculation methods of steady operation. The next part is theoreticly dedicated to the technical losses, possibilities of their influencing and their calculation. In the practical part is carried out the choice of calculation method of steady operation. This method is implicated into the proposed program in programming environment MATLAB.Furthermore, on the basis of a partial measurement in the distribution network and using the proposed program are determined the sizes of offtakes of mesh network. For the existing mesh network is designed its radial operation. In the last part are calculated the losses of this network for both of these mentioned operations.
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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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|
|
SAIDI and SAIFI Calculation for a Low Voltage Distribution Networks in Mesh Configuration
Dohnal, Josef ; Souček, Jan (referee) ; Paar, Martin (advisor)
This diploma thesis aims to briefly interpret problems relating to continuity of distribution of electrical energy in a distribution network of low voltage. It also mentions methods of calculation of a distribution system´s reliability which are the most used in practice. Next, there is a chapter dedicated to how distribution networks are projected and operated in the Czech Republic and in the United Kingdom. Based on experiences with meshed networks operation this thesis designs protection of meshed distribution network of low voltage. In the end, a non-sequential method of Monte Carlo is used to calculate System Average Interruption Index (SAIDI) and System Average Interruption Frequency index (SAIFI).
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|
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Power Losses Calculation Depending on Distribution Network Configuration
Domes, František ; Souček, Jan (referee) ; Paar, Martin (advisor)
This master‘s thesis deals with the calculation of losses depending on the configuration of the distribution network. The first part focuses on the general theory regarding some used calculation methods of steady operation. The next part is theoreticly dedicated to the technical losses, possibilities of their influencing and their calculation. In the practical part is carried out the choice of calculation method of steady operation. This method is implicated into the proposed program in programming environment MATLAB.Furthermore, on the basis of a partial measurement in the distribution network and using the proposed program are determined the sizes of offtakes of mesh network. For the existing mesh network is designed its radial operation. In the last part are calculated the losses of this network for both of these mentioned operations.
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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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