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Design of presentation electric switchboard for LV
Hlaváč, Jan ; Štefanov, Marek (referee) ; Bátora, Branislav (advisor)
This master’s thesis deals with the design of electric switchgear for low voltage, which will serve for presentation purposes. The switchgear is analogy of the modular system MNS 3.0, which includes the latest equipment of ABB Ltd. that is currently available on the market. Switchgears of this type are widely used in industry primarily for controlling motor units. For this reason, in the switchgear there are located motor starters in various performances, as well as distribution modules. In addition, the switchgear has an automatic transfer switch function in case of failure of one of the power supplies. The complete documentation of the switchgear is processed in the professional software EPLAN Electric P8 with use of the 3D software EPLAN Pro Panel for modelling device compartments. The final part of the thesis is the calculation of the maximum cable lengths that a potential customer can connect to the switchgear. In addition, an analysis of the power and control circuits was carried out for voltage drop calculations, as well as the effect of these voltage drops and capacitance of long control cables on the actuation of contactors.
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Telemetry and Dispatch Control of Low Voltage Grid
Gála, Michal ; Vaculík, Petr (referee) ; Toman, Petr (advisor)
The contents of this thesis are the introduction to mesh grids, the method of dispatch control of these grids and the description of technology used in mesh grids distribution nodes in the city of Brno. This thesis also describes low voltage switchgears used in these types of grids. The development of dispatch control in ECD company is also mentioned. The development describes the grid dispatch control methods prior to implementing the OMS system and the changes which followed after the implementation. The process improvements of the new system resulting from this thesis can be found in this thesis as well. The improvements are incorporated in the OMS system and are used for more efficient dispatch control of the low voltage mesh grids. There is a more detailed analysis of the mesh grid Brno – Bohunice in the practical part of this thesis. The practical part contains analyses of mesh grids stabilized conditions measurements and analyses of mesh grids fault conditions measurements. The analyses assess the power load in transformers, minimal and maximal phase current and maximal power load at the time they were observed. The analysis of the measured data is accompanied by the assessment of differences in current phase measurements and differences in voltage phase and combined measurements. The result, based on the analysis and collection of the data, is a proposition of adding switchgears for the support of the dispatch control of the mesh grid Brno – Bohunice. In the summary of the thesis there is a comparison of the result of the factual and theoretical analysis. An experimental model of the mesh grid Brno – Bohunice was created in PS CAD software as a part of the theoretical analysis.
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Design of switchgear system
Róža, Štefan ; Slavata, Petr (referee) ; Kadlec, Radim (advisor)
The thesis depicts the substation of low voltage switchgear design (nn) based on the back scheme of its connection. In the first part of the switchgear design nn the thesis deals with the adjustment of the back connection scheme and its analysis necessary for continuation of its switchgear designing. The main part of the thesis describes the scheme creation in a computer program, the implementation of certain computations requisite for safe and failure-free operation of the station. Here, the thesis points out the solutions of conditions, where the back scheme does not agree with the calculated results. The circuit was tested for voltage drop and load decomposition, symmetrical 3-phase short circuit and 1-phase short circuit. Further, the thesis dwells on the switchgear designing of low voltage switchgear. Finally was created in 3D visualization and treated bid for the material needed for the production of switchgear system, production of switchgear system and UPS.
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Investigation on the Interaction between Construction Materials and Switching Arc in Low Voltage Switching Devices
Šimek, David ; Slavíček, Pavel (referee) ; Mindl,, Pavel (referee) ; Kloc, Petr (advisor)
The doctoral thesis is focused on the interaction of construction materials and the switching arc in low voltage switchgear. An issue of selected low-voltage electrical devices, electric arc in electrical devices, and its diagnostics using optical emission spectroscopy and high-speed video are discussed at the theoretical level. The main part of the work is an experimental examination of samples of selected high-performance industrial plastics. A series of tests of resistance to an electric arc were performed on these plastics. The electrical parameters of the switching process, the weight losses of the material of the quenching chambers when applying various power parameters were evaluated from the experiments. The empirical equations were determined for the calculation of the loss of individual materials in a specific configuration. Furthermore, the influence of the used material on the behavior of the electric arc in the extinguishing chamber made of these plastics was investigated. A high-speed video was recorded, the time evolution of the pressure inside the chamber, the electrical parameters of the arc, and the time-resolved evolution of the radiation spectra were measured using atomic emission spectroscopy in these measurements. The relative composition of the plasma was identified from the radiation spectra, and the time evolution of the relative contamination of the discharge area by the main contact material and the selected vapors of the used plastics was created. The last important parameter of the electric arc is its temperature, which was also calculated from the radiation spectra. A comparison of individual plastics and their applicability for applications in contact with electric arc was performed based on the obtained data.
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USING MODERN NUMERIC METHODS IN DESIGN OF LOW VOLTAGE CIRCUIT BREAKERS
Dostál, Lukáš ; Hüttner, Ľudovít (referee) ; Petráček, Miloš (referee) ; Aubrecht, Vladimír (advisor)
The theses is focused on efficient use of numerical methods in development of low-voltage switching devices, namely to create a physically correct and reliable numerical model of the temperature field to find an application in the design of the current path of a device for various operating conditions. The creation of this numerical model requires not only correct inclusion of all modes of heat transfer - conduction, convection and radiation, but also correct solution of problematic transient resistance - both electrical and thermal in electrical contacts at different stages of usage. Therefore an essential part of the theses forms a thorough experimental analysis of the necessary material properties and dependencies which forms input data for the numerical model that is based on the finite volume method. The last part of the theses deals with debugging and verification of numerical model to correspond with experimentally obtained data. The result of the theses is the numerical model which is able to solve correctly both steady and various transient states of swiching devices.
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Investigation on the Interaction between Construction Materials and Switching Arc in Low Voltage Switching Devices
Šimek, David ; Slavíček, Pavel (referee) ; Mindl,, Pavel (referee) ; Kloc, Petr (advisor)
The doctoral thesis is focused on the interaction of construction materials and the switching arc in low voltage switchgear. An issue of selected low-voltage electrical devices, electric arc in electrical devices, and its diagnostics using optical emission spectroscopy and high-speed video are discussed at the theoretical level. The main part of the work is an experimental examination of samples of selected high-performance industrial plastics. A series of tests of resistance to an electric arc were performed on these plastics. The electrical parameters of the switching process, the weight losses of the material of the quenching chambers when applying various power parameters were evaluated from the experiments. The empirical equations were determined for the calculation of the loss of individual materials in a specific configuration. Furthermore, the influence of the used material on the behavior of the electric arc in the extinguishing chamber made of these plastics was investigated. A high-speed video was recorded, the time evolution of the pressure inside the chamber, the electrical parameters of the arc, and the time-resolved evolution of the radiation spectra were measured using atomic emission spectroscopy in these measurements. The relative composition of the plasma was identified from the radiation spectra, and the time evolution of the relative contamination of the discharge area by the main contact material and the selected vapors of the used plastics was created. The last important parameter of the electric arc is its temperature, which was also calculated from the radiation spectra. A comparison of individual plastics and their applicability for applications in contact with electric arc was performed based on the obtained data.
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Telemetry and Dispatch Control of Low Voltage Grid
Gála, Michal ; Vaculík, Petr (referee) ; Toman, Petr (advisor)
The contents of this thesis are the introduction to mesh grids, the method of dispatch control of these grids and the description of technology used in mesh grids distribution nodes in the city of Brno. This thesis also describes low voltage switchgears used in these types of grids. The development of dispatch control in ECD company is also mentioned. The development describes the grid dispatch control methods prior to implementing the OMS system and the changes which followed after the implementation. The process improvements of the new system resulting from this thesis can be found in this thesis as well. The improvements are incorporated in the OMS system and are used for more efficient dispatch control of the low voltage mesh grids. There is a more detailed analysis of the mesh grid Brno – Bohunice in the practical part of this thesis. The practical part contains analyses of mesh grids stabilized conditions measurements and analyses of mesh grids fault conditions measurements. The analyses assess the power load in transformers, minimal and maximal phase current and maximal power load at the time they were observed. The analysis of the measured data is accompanied by the assessment of differences in current phase measurements and differences in voltage phase and combined measurements. The result, based on the analysis and collection of the data, is a proposition of adding switchgears for the support of the dispatch control of the mesh grid Brno – Bohunice. In the summary of the thesis there is a comparison of the result of the factual and theoretical analysis. An experimental model of the mesh grid Brno – Bohunice was created in PS CAD software as a part of the theoretical analysis.
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USING MODERN NUMERIC METHODS IN DESIGN OF LOW VOLTAGE CIRCUIT BREAKERS
Dostál, Lukáš ; Hüttner, Ľudovít (referee) ; Petráček, Miloš (referee) ; Aubrecht, Vladimír (advisor)
The theses is focused on efficient use of numerical methods in development of low-voltage switching devices, namely to create a physically correct and reliable numerical model of the temperature field to find an application in the design of the current path of a device for various operating conditions. The creation of this numerical model requires not only correct inclusion of all modes of heat transfer - conduction, convection and radiation, but also correct solution of problematic transient resistance - both electrical and thermal in electrical contacts at different stages of usage. Therefore an essential part of the theses forms a thorough experimental analysis of the necessary material properties and dependencies which forms input data for the numerical model that is based on the finite volume method. The last part of the theses deals with debugging and verification of numerical model to correspond with experimentally obtained data. The result of the theses is the numerical model which is able to solve correctly both steady and various transient states of swiching devices.
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Design of presentation electric switchboard for LV
Hlaváč, Jan ; Štefanov, Marek (referee) ; Bátora, Branislav (advisor)
This master’s thesis deals with the design of electric switchgear for low voltage, which will serve for presentation purposes. The switchgear is analogy of the modular system MNS 3.0, which includes the latest equipment of ABB Ltd. that is currently available on the market. Switchgears of this type are widely used in industry primarily for controlling motor units. For this reason, in the switchgear there are located motor starters in various performances, as well as distribution modules. In addition, the switchgear has an automatic transfer switch function in case of failure of one of the power supplies. The complete documentation of the switchgear is processed in the professional software EPLAN Electric P8 with use of the 3D software EPLAN Pro Panel for modelling device compartments. The final part of the thesis is the calculation of the maximum cable lengths that a potential customer can connect to the switchgear. In addition, an analysis of the power and control circuits was carried out for voltage drop calculations, as well as the effect of these voltage drops and capacitance of long control cables on the actuation of contactors.
|
|
|
Design of switchgear system
Róža, Štefan ; Slavata, Petr (referee) ; Kadlec, Radim (advisor)
The thesis depicts the substation of low voltage switchgear design (nn) based on the back scheme of its connection. In the first part of the switchgear design nn the thesis deals with the adjustment of the back connection scheme and its analysis necessary for continuation of its switchgear designing. The main part of the thesis describes the scheme creation in a computer program, the implementation of certain computations requisite for safe and failure-free operation of the station. Here, the thesis points out the solutions of conditions, where the back scheme does not agree with the calculated results. The circuit was tested for voltage drop and load decomposition, symmetrical 3-phase short circuit and 1-phase short circuit. Further, the thesis dwells on the switchgear designing of low voltage switchgear. Finally was created in 3D visualization and treated bid for the material needed for the production of switchgear system, production of switchgear system and UPS.
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