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Comparison of the Methods Used to Low Level DC Voltage Measurement
Obšilová, Lucie
This paper deals with comparison of three methods used to measure low level DC voltage. It is about Reference Step Method, potentiometric method and direct method. Measurement was held in cooperation with the Czech metrology institute. Comparison of the methods consist of a graphic comparison and a key comparison. Results showed good agreement of all methods except for potentiometric method at one range of a device under test.
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Low level DC voltage measurement
Obšilová, Lucie ; Nováková Zachovalová, Věra (referee) ; Havlíková, Marie (advisor)
This thesis deals with low level DC voltage measurement by three methods. First part of this thesis describes each method. It is about potentiometric method, reference step method and direct method. This thesis also describes Josephson voltage standard which was used for calibration nanovoltmeter and Zener reference. The theoretical part of this thesis also deals with the evaluation of key comparison data. The main goal of this thesis is the comparison of methods used to measure low level DC voltage. The practical part of the thesis deals with the implementation of measurement with all methods in cooperation with Czech metrology institute. The measured values are processed including uncertainty evaluations. The final part of this thesis focuses on comparison of measurement methods. The key comparison reference value and the degree of equivalence of the measurement of each method are determined. Next part of comparison consisted of graphic comparison of methods. The end of the thesis contains evaluation of the achieved results.
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Voltage quality in DC grids
Faktor, Richard ; Kraus, Jan (referee) ; Drápela, Jiří (advisor)
This diploma thesis deals with elektrical power quality in DC grids. Electrical power is commodity and therefore it must be represented not just with quantitative, but also with qualitative parameters. Nowadays, there is an increasing demand for bigger implementation of renewable energy sources and more efficient power systems, which motivates installation of DC grids. However, development of DC grids is decelerated by lack of standardization alson in power quality. The work includes definition of power quality parameters and their measurement methodology.
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Meaurement process automatization of Zener reference
Bábek, Tomáš ; Nováková Zachovalová, Věra (referee) ; Havlíková, Marie (advisor)
This thesis deals with metrology specialized to DC voltage. In the begining of thesis is explanation of technical terms from metrology, summarization of units from International System and explanation of the standards and its kinds in the context of metrology. Primary standards of DC voltage based on Zener diodes and Josephson effect are described as well. In cooperation with Czech metrology institute in Brno this work is focused on automatization of measuring Zener reference standards (ZRS). Goal of this project is to automatize the measuring of Zener reference standards and its relationship with Josephson voltage system using scanner. To do this, there is a need to find out offsets, that can develop on scanner's channels. There is a theoretical analysis of measuring made on the scanner and their uncertainties. Aim of the solution is computation of scanner channels offsets using everyday automatic measuring the system of Zener reference standards (ZRS). For measuring the LabView was used and for computing the data from measured values the Matlab was used. This thesis should short the time needed when measuring DC voltage references, measure values of DC voltage standards and set the scanner channels offsets. In the end there is a summarization of offsets measured on individual scanner channels.
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Short Circuit Currents in DC Systems
Kolařík, Robin ; Geschwinder, Lukáš (referee) ; Paar, Martin (advisor)
The bachelor thesis deals with the analysis of short-circuit currents in DC systems. The thesis introduces the possibility of application of low voltage DC distribution in commercial and industrial buildings. The second part is focused to high voltage direct current transmission. The practical part deals with the calculation of short-circuit currents of individual elements and subsequently with short-circuit conditions in the DC network. At the end of the work are evaluated advantages and disadvantages between AC and DC voltage and suitability of use in given areas.
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Short Circuit Currents in DC Systems
Kolařík, Robin ; Geschwinder, Lukáš (referee) ; Paar, Martin (advisor)
The bachelor thesis deals with the analysis of short-circuit currents in DC systems. The thesis introduces the possibility of application of low voltage DC distribution in commercial and industrial buildings. The second part is focused to high voltage direct current transmission. The practical part deals with the calculation of short-circuit currents of individual elements and subsequently with short-circuit conditions in the DC network. At the end of the work are evaluated advantages and disadvantages between AC and DC voltage and suitability of use in given areas.
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Comparison of the Methods Used to Low Level DC Voltage Measurement
Obšilová, Lucie
This paper deals with comparison of three methods used to measure low level DC voltage. It is about Reference Step Method, potentiometric method and direct method. Measurement was held in cooperation with the Czech metrology institute. Comparison of the methods consist of a graphic comparison and a key comparison. Results showed good agreement of all methods except for potentiometric method at one range of a device under test.
|
|
|
Voltage quality in DC grids
Faktor, Richard ; Kraus, Jan (referee) ; Drápela, Jiří (advisor)
This diploma thesis deals with elektrical power quality in DC grids. Electrical power is commodity and therefore it must be represented not just with quantitative, but also with qualitative parameters. Nowadays, there is an increasing demand for bigger implementation of renewable energy sources and more efficient power systems, which motivates installation of DC grids. However, development of DC grids is decelerated by lack of standardization alson in power quality. The work includes definition of power quality parameters and their measurement methodology.
|
|
|
Low level DC voltage measurement
Obšilová, Lucie ; Nováková Zachovalová, Věra (referee) ; Havlíková, Marie (advisor)
This thesis deals with low level DC voltage measurement by three methods. First part of this thesis describes each method. It is about potentiometric method, reference step method and direct method. This thesis also describes Josephson voltage standard which was used for calibration nanovoltmeter and Zener reference. The theoretical part of this thesis also deals with the evaluation of key comparison data. The main goal of this thesis is the comparison of methods used to measure low level DC voltage. The practical part of the thesis deals with the implementation of measurement with all methods in cooperation with Czech metrology institute. The measured values are processed including uncertainty evaluations. The final part of this thesis focuses on comparison of measurement methods. The key comparison reference value and the degree of equivalence of the measurement of each method are determined. Next part of comparison consisted of graphic comparison of methods. The end of the thesis contains evaluation of the achieved results.
|
|
|
Meaurement process automatization of Zener reference
Bábek, Tomáš ; Nováková Zachovalová, Věra (referee) ; Havlíková, Marie (advisor)
This thesis deals with metrology specialized to DC voltage. In the begining of thesis is explanation of technical terms from metrology, summarization of units from International System and explanation of the standards and its kinds in the context of metrology. Primary standards of DC voltage based on Zener diodes and Josephson effect are described as well. In cooperation with Czech metrology institute in Brno this work is focused on automatization of measuring Zener reference standards (ZRS). Goal of this project is to automatize the measuring of Zener reference standards and its relationship with Josephson voltage system using scanner. To do this, there is a need to find out offsets, that can develop on scanner's channels. There is a theoretical analysis of measuring made on the scanner and their uncertainties. Aim of the solution is computation of scanner channels offsets using everyday automatic measuring the system of Zener reference standards (ZRS). For measuring the LabView was used and for computing the data from measured values the Matlab was used. This thesis should short the time needed when measuring DC voltage references, measure values of DC voltage standards and set the scanner channels offsets. In the end there is a summarization of offsets measured on individual scanner channels.
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