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Design of a measurement circuit for electrochemical cells cycling in SEM chamber
Tran, Quoc Bao ; Trochta, David (referee) ; Klvač, Ondřej (advisor)
This diploma thesis deals with the design of a measurement circuit consisting of two separate modules for measuring electric current in the order of nanoamperes (nA) for the in-situ analysis of lithium-ion cells in microscopic dimensions. The aim of this thesis is to build a prototype measurement circuit to solve the electromagnetic interference (EMI) problems associated with in-situ analysis and to perform subsequent testing of this circuit or modules. The diploma thesis is divided into two parts, namely a theoretical and an experimental part. In the theoretical part, research on electrochemical cells is described, where the focus is directed towards lithium-ion cells. The principle of the function of these cells is described and research on their degradation mechanisms has also been carried out. Furthermore, the testing methods of lithium-ion cells such as GCPL, OCV and CV have been described. In the theoretical part, the in-situ experiments already performed at Thermo Fisher Scientific Brno are described. One experiment consisted of assembling an electrochemical cell on a MEMS chip and the other experiment was performed using a micromanipulator as a current collector. Measured data were affected by electromagnetic interference. The practical part discusses the design of a measurement circuit that would theoretically solve the problems of measuring very small currents from an EMI perspective. It also describes how the measurement circuit was tested.
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Measurement and analysis of audio-frequency differential disturbances in distribution systems
Doseděl, Tomáš ; Havránek, Zdeněk (referee) ; Drápela, Jiří (advisor)
This thesis deals with voltage disturbances in audio-frequency propagated in distribution networks. In the theoretical part, a creation and effect of these interferences are discussed as well as current methods of their measurement. In the practical part of the thesis, a measurement device based on a frequency filter was developed. This measurement device is able to measure audio-frequency disturbances up to 250kHz without suppresion of audio-frequency disturbances. The maximum frequency on the output is limited by either 125kHz or 250 kHz filter.
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Optimum layout of workplaces security checks of passengers
Bordovský, Lukáš ; Janík, Radomír (referee) ; Šplíchal, Miroslav (advisor)
The final master’s thesis analyzes the individual elements of Security control workplace and solves their optimization with respect to the rulemaking side of things, and integration into the existing space layout with a vision of the increasing demand for transport. Solves the issue of electromagnetic interference elimination in the detection equipment and suggests possible solutions to overcome them. The work is primarily related to the Prague - Ruzyne airport.
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Virtual Measurement System for the Anechoic Chambers
Váško, Ondřej ; Soldán, Josef (referee) ; Dřínovský, Jiří (advisor)
Master thesis examines a selected part of electromagnetic compatibility. In this work, there is theoretically discussed how electromagnetic interference appears and how is spread through free space environment. To eliminate ambient interference signals, the measurements have been performed in anechoic chamber where the undesirable interference signals were suppressed. In the thesis, there are also described parameters of EMI receivers and limits of electromagnetic interference. The description of calculations of the antenna height for finding maximum intensity of electric field strength for standard measurement distance has been made. For proposed transformed measurement distance, calculations of intensity electric field with addition of parameters measuring antenna and object under test were performed. Correction curves for conversion intensity electric field have been obtained as the result.
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Způsoby ochrany elektronických komponent motorových vozidel
Němec, David
The bachelor’s thesis „Methods of protection of electronic components of motor vehicles“ in the introductory part acquaints the reader with electrical faults occurring in motor vehicles. The following section describes methods and means to protect against these faults. Furthermore, the work describes the current methods of protection of electronic control units and legislative requirements that impose obligations on manufacturers and suppliers in the design of protective devices for electronic modules of motor vehicles. The last part describes the means to protect the communication networks of motor vehicles against electromagnetic interference and electrostatic discharge.
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Measurement and analysis of audio-frequency differential disturbances in distribution systems
Doseděl, Tomáš ; Havránek, Zdeněk (referee) ; Drápela, Jiří (advisor)
This thesis deals with voltage disturbances in audio-frequency propagated in distribution networks. In the theoretical part, a creation and effect of these interferences are discussed as well as current methods of their measurement. In the practical part of the thesis, a measurement device based on a frequency filter was developed. This measurement device is able to measure audio-frequency disturbances up to 250kHz without suppresion of audio-frequency disturbances. The maximum frequency on the output is limited by either 125kHz or 250 kHz filter.
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Optimum layout of workplaces security checks of passengers
Bordovský, Lukáš ; Janík, Radomír (referee) ; Šplíchal, Miroslav (advisor)
The final master’s thesis analyzes the individual elements of Security control workplace and solves their optimization with respect to the rulemaking side of things, and integration into the existing space layout with a vision of the increasing demand for transport. Solves the issue of electromagnetic interference elimination in the detection equipment and suggests possible solutions to overcome them. The work is primarily related to the Prague - Ruzyne airport.
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Virtual Measurement System for the Anechoic Chambers
Váško, Ondřej ; Soldán, Josef (referee) ; Dřínovský, Jiří (advisor)
Master thesis examines a selected part of electromagnetic compatibility. In this work, there is theoretically discussed how electromagnetic interference appears and how is spread through free space environment. To eliminate ambient interference signals, the measurements have been performed in anechoic chamber where the undesirable interference signals were suppressed. In the thesis, there are also described parameters of EMI receivers and limits of electromagnetic interference. The description of calculations of the antenna height for finding maximum intensity of electric field strength for standard measurement distance has been made. For proposed transformed measurement distance, calculations of intensity electric field with addition of parameters measuring antenna and object under test were performed. Correction curves for conversion intensity electric field have been obtained as the result.
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