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Draft sources 1000A AC current sensors for calibration
Klimeš, Jan ; Vetiška, Vojtěch (referee) ; Dohnal, Petr (advisor)
This bachelor thesis deals with design and construction of device for precise measurement of 1000 A alternate current. This thesis theoretically discusses the possibilities of conventional solutions, such as current transformers, as well as modern methods in the form of current sensors. The output of this thesis is a solution of problems with accuracy and discussion of other possible ways to reduce systematic error. The thesis discusses structure of the current transformer, the digitalizing of the signal and its usage as an input for engineering units. The device is then tested for final accuracy.
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Measurement of roughness of the laser cutting edge by Yb-YAG laser
Dočekal, Miroslav ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
The project carried out in the bachelor's degree program B - STG (“Mechanical Engineering Technology”, 2303R002), evaluates the roughness of the cutting edges of steel plates cut by laser according to the ČSN EN ISO 9013 standard. The test samples were cut by Yb - YAG laser. In total, 11 samples were measured. The samples represent three kinds of material and were cut by two ways of laser cutting; the fusion method and the oxidation method. The samples of stainless steel X10CrNi18-8 were cut by the fusion method and the remaining samples of the DC 01 steel and S235 JRG steel were cut by the oxidation method. The samples were evaluated according to the ČSN EN ISO 9013 standard. The standard evaluates the quality of cut in thermal cutting and classifies individual cuts into accuracy classes. The samples of stainless steel fall into the first and second classes of accuracy. The samples of structural steel all fall into the second class of accuracy. This classification is the outcome of the practical part of the project. The theoretical part deals with the basic principle of laser, its parts, the industrial use of lasers and the lasers most commonly used in industry. It focuses particularly on laser cutting and the parameters which affect the quality of the cut in laser cutting. The measuring of roughness and the ČSN EN ISO 9013 standard are also described.
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Current Transformers and Current Sensors Confrontation
Popek, Jiří ; Bok, Jaromír (referee) ; Topolánek, David (advisor)
Current transformers and current sensors are devices which are mostly used for current measurement in high voltage systems. This devices transform measured currents to range which are workable for measurement and protection devices. Current transformers have been using for current measurement since electric system was built. Current sensors are using for measurement after applying digital devices in their secondary circuits. Theoretical part includes fourth and fifth chapter. These chapters contain construction analysis and characteristic points for both devices. Practical part is in chapter six. This chapter consists results from laboratory measurement. Results are used for verification with theoretical part of the thesis. Accuracy class in nominal range and progress for measurement error in overcurrent range was verified for tested devices. Conclusion of this thesis comparing properties and summarises results from laboratory measurement.
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Low power current transformers
Zolich, Ladislav ; Hrabčík,, Miroslav (referee) ; Dostál, Lukáš (advisor)
Master‘s thesis is focused on current instrument transformers, current sensors and low power current transformers. Discussion is made on advantages and disadvantages of each measuring principle. Low power current transformers is then designed and manufactured. Manufactured LPCT is then measured for accuracy class. Results are then compared.
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Low power current transformers
Zolich, Ladislav ; Hrabčík,, Miroslav (referee) ; Dostál, Lukáš (advisor)
Master‘s thesis is focused on current instrument transformers, current sensors and low power current transformers. Discussion is made on advantages and disadvantages of each measuring principle. Low power current transformers is then designed and manufactured. Manufactured LPCT is then measured for accuracy class. Results are then compared.
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Draft sources 1000A AC current sensors for calibration
Klimeš, Jan ; Vetiška, Vojtěch (referee) ; Dohnal, Petr (advisor)
This bachelor thesis deals with design and construction of device for precise measurement of 1000 A alternate current. This thesis theoretically discusses the possibilities of conventional solutions, such as current transformers, as well as modern methods in the form of current sensors. The output of this thesis is a solution of problems with accuracy and discussion of other possible ways to reduce systematic error. The thesis discusses structure of the current transformer, the digitalizing of the signal and its usage as an input for engineering units. The device is then tested for final accuracy.
|
|
|
Current Transformers and Current Sensors Confrontation
Popek, Jiří ; Bok, Jaromír (referee) ; Topolánek, David (advisor)
Current transformers and current sensors are devices which are mostly used for current measurement in high voltage systems. This devices transform measured currents to range which are workable for measurement and protection devices. Current transformers have been using for current measurement since electric system was built. Current sensors are using for measurement after applying digital devices in their secondary circuits. Theoretical part includes fourth and fifth chapter. These chapters contain construction analysis and characteristic points for both devices. Practical part is in chapter six. This chapter consists results from laboratory measurement. Results are used for verification with theoretical part of the thesis. Accuracy class in nominal range and progress for measurement error in overcurrent range was verified for tested devices. Conclusion of this thesis comparing properties and summarises results from laboratory measurement.
|
|
|
Measurement of roughness of the laser cutting edge by Yb-YAG laser
Dočekal, Miroslav ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
The project carried out in the bachelor's degree program B - STG (“Mechanical Engineering Technology”, 2303R002), evaluates the roughness of the cutting edges of steel plates cut by laser according to the ČSN EN ISO 9013 standard. The test samples were cut by Yb - YAG laser. In total, 11 samples were measured. The samples represent three kinds of material and were cut by two ways of laser cutting; the fusion method and the oxidation method. The samples of stainless steel X10CrNi18-8 were cut by the fusion method and the remaining samples of the DC 01 steel and S235 JRG steel were cut by the oxidation method. The samples were evaluated according to the ČSN EN ISO 9013 standard. The standard evaluates the quality of cut in thermal cutting and classifies individual cuts into accuracy classes. The samples of stainless steel fall into the first and second classes of accuracy. The samples of structural steel all fall into the second class of accuracy. This classification is the outcome of the practical part of the project. The theoretical part deals with the basic principle of laser, its parts, the industrial use of lasers and the lasers most commonly used in industry. It focuses particularly on laser cutting and the parameters which affect the quality of the cut in laser cutting. The measuring of roughness and the ČSN EN ISO 9013 standard are also described.
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