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Aggregation and propagation of disturbances in the transmission system
Šedivý, Tomáš ; Rajský,, František (referee) ; Drápela, Jiří (advisor)
This thesis is devoted to the analysis and simulation of disturbance phenomena in the transmission system of the Czech Republic with emphasis on harmonic voltage distortion. A simulation model was developed in PSCAD environment, which allows to study the propagation of harmonic components in a congested system with multiple interconnected substations under different operating scenarios. The simulation results provide a deeper understanding of the aspects affecting the propagation of mainly harmonics in the network and lead to suggestions on how to effectively analyze the propagation of disturbances on a larger scale network.
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Measurement of passive frequency crossovers for loudspeaker systems
Holínský, Jan ; Hanák, Pavel (referee) ; Balík, Miroslav (advisor)
The content of the master´s thesis is to approach the issue of measuring the characteristics of passive frequency crossover. The work describes individual types of measured characteristics and their possibility of measurement. Then the work describes design of modules for measurement characteristics of passive frequency crossover (shunt, resistive load and amplifier). These modules were made and tested for its functions. For the amplifier is then made a second design for fulfilment requirements. The second version isn’t made in this work. At the end of the work was prepared the theoretical part of the laboratory task: Measurement of characteristics of passive frequency crossover, including protocol.
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Testing of Distance Protection
Holub, Martin ; Vaculík, Petr (referee) ; Orságová, Jaroslava (advisor)
Bachelor thesis Testing of Distance Protection introduces us to the issue of distance protection and its detailed principle. It deals with its individual elements and shows us different types of impedance characteristics of measuring elements. It describes a situation that occurs during a short circuit on a homogeneous line, then introduces us to a DC component compensation and discuss the effect of distance protection degrees. Among other things, it deals with the digital distance protections and settings of their characteristics. Finally the theoretical part evaluates advantages over other protections and advantages and disadvantages of distance protections themselves. Thesis will introduce the digital distance protection REL 511 from the company ABB and characterizes its settings, parameters and connection to the testing equipment OMICRON CMC 256plus, which is used to control the protection via personal computer. Description of the programs OMICRON Test Universe and CAP 540 and their settings follows. This section can serve as a manual for future operators of REL 511 protection. The work provides a suitable methodology for measuring the operating characteristics and uses this method in practice. Given the limited version of the OMICRON Test Universe, polygonal tripping characteristics are measured in the module "Distance" with the shot test. Evaluation of measurements is summarized at the end.
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Loudspeaker Box for Laboratory Measurements of Loudspeaker Impedance
Nevole, Tomáš ; Káňa, Ladislav (referee) ; Schimmel, Jiří (advisor)
In this thesis there are solved problems of design and construction of a universal modular loudspeaker box, which should serve for laboratory measurements of broadband electro-magnetic loudspeaker’s impedance. These measurements should demonstrate how the electric parameters are changed by changing the acoustic impedance of surrounding into which the speaker transmits. In the first part there is explained necessary theory for solving the task, such as way of sound’s transmission in the environment, variable sorts of speakers and their characteristics. A special focus is given to description of the electro-magnetic speaker’s parameters and construction that was used for the loudspeaker box. Then there are introduced needed mathematical formulas for algebraic design of the loudspeaker box, various types of the loudspeaker boxes (open, closed, vented) and their parameters. In this thesis there is also solved the problem with leaks and settled the matter, if it is better to build one modular box or 2 or 3 separate boxes. Most important characteristics are the impedance characteristics for this thesis but the SPL characteristics are also included. Unfortunately the simulating programs couldn’t generate the hodographs of impedance. After the algebraic calculations, in the thesis there are presented outputs from simulation programs Unibox 408 and WinISD 0.6. The outputs also are compared with the algebraic calculations. In the last part of the thesis there is already described the own construction of the loudspeaker box and presented results from the box’s measuring in the anechoic chamber (in the laboratory of electro-acoustic). The measuring of the modular impedance characteristic was realized on the single speaker and all the boxes. The measuring of the SPL (sound pressure level) characteristic was realized on the boxes only. All these results are compared with the calculations and simulations and the inaccuracies are substantiated in the end. The comparing of the manufacturer’s characteristics with the measured characteristics is also included.
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Analysis of the Parasitic Bonds in the RFI Filters
Pišťák, Ondřej ; Vyskočil, Pavel (referee) ; Dřínovský, Jiří (advisor)
These diploma thesis deals with analysis of parasitic elements of EMI filters. It is desirable that the attenuation characteristics can be predicted with the help of the known filter’s schematic even at higher frequencies, where the parasitic elements of the passive components have to be taken into account. The analysis also includes the creation of real circuitry of an EMI filter. The component values are estimated according to this basic model.
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Measurement of passive frequency crossovers for loudspeaker systems
Holínský, Jan ; Hanák, Pavel (referee) ; Balík, Miroslav (advisor)
The content of the master´s thesis is to approach the issue of measuring the characteristics of passive frequency crossover. The work describes individual types of measured characteristics and their possibility of measurement. Then the work describes design of modules for measurement characteristics of passive frequency crossover (shunt, resistive load and amplifier). These modules were made and tested for its functions. For the amplifier is then made a second design for fulfilment requirements. The second version isn’t made in this work. At the end of the work was prepared the theoretical part of the laboratory task: Measurement of characteristics of passive frequency crossover, including protocol.
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Testing of Distance Protection
Holub, Martin ; Vaculík, Petr (referee) ; Orságová, Jaroslava (advisor)
Bachelor thesis Testing of Distance Protection introduces us to the issue of distance protection and its detailed principle. It deals with its individual elements and shows us different types of impedance characteristics of measuring elements. It describes a situation that occurs during a short circuit on a homogeneous line, then introduces us to a DC component compensation and discuss the effect of distance protection degrees. Among other things, it deals with the digital distance protections and settings of their characteristics. Finally the theoretical part evaluates advantages over other protections and advantages and disadvantages of distance protections themselves. Thesis will introduce the digital distance protection REL 511 from the company ABB and characterizes its settings, parameters and connection to the testing equipment OMICRON CMC 256plus, which is used to control the protection via personal computer. Description of the programs OMICRON Test Universe and CAP 540 and their settings follows. This section can serve as a manual for future operators of REL 511 protection. The work provides a suitable methodology for measuring the operating characteristics and uses this method in practice. Given the limited version of the OMICRON Test Universe, polygonal tripping characteristics are measured in the module "Distance" with the shot test. Evaluation of measurements is summarized at the end.
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Loudspeaker Box for Laboratory Measurements of Loudspeaker Impedance
Nevole, Tomáš ; Káňa, Ladislav (referee) ; Schimmel, Jiří (advisor)
In this thesis there are solved problems of design and construction of a universal modular loudspeaker box, which should serve for laboratory measurements of broadband electro-magnetic loudspeaker’s impedance. These measurements should demonstrate how the electric parameters are changed by changing the acoustic impedance of surrounding into which the speaker transmits. In the first part there is explained necessary theory for solving the task, such as way of sound’s transmission in the environment, variable sorts of speakers and their characteristics. A special focus is given to description of the electro-magnetic speaker’s parameters and construction that was used for the loudspeaker box. Then there are introduced needed mathematical formulas for algebraic design of the loudspeaker box, various types of the loudspeaker boxes (open, closed, vented) and their parameters. In this thesis there is also solved the problem with leaks and settled the matter, if it is better to build one modular box or 2 or 3 separate boxes. Most important characteristics are the impedance characteristics for this thesis but the SPL characteristics are also included. Unfortunately the simulating programs couldn’t generate the hodographs of impedance. After the algebraic calculations, in the thesis there are presented outputs from simulation programs Unibox 408 and WinISD 0.6. The outputs also are compared with the algebraic calculations. In the last part of the thesis there is already described the own construction of the loudspeaker box and presented results from the box’s measuring in the anechoic chamber (in the laboratory of electro-acoustic). The measuring of the modular impedance characteristic was realized on the single speaker and all the boxes. The measuring of the SPL (sound pressure level) characteristic was realized on the boxes only. All these results are compared with the calculations and simulations and the inaccuracies are substantiated in the end. The comparing of the manufacturer’s characteristics with the measured characteristics is also included.
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