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The comparison of acoustic properties of guitars from the same product line
Trávníčková, Hana ; Indrák, Michal (referee) ; Jirásek, Ondřej (advisor)
This work is dealing with acoustic features of Furch guitars. In theoretical introduction is possible to find an information about basic characteristics of a tone. Following chapter about acoustic guitars is dealing even with mostly used types of woods for their manufacturing. In special chapter are described spectres of signals, LPC analysis, sound radiation of instruments and Chladni figures. Mentioned terms have been evaluated from measurements and are available in practical part of this work also including description of implementation of the measurement. As an output of this work is a comparison of acoustic features of measured guitars, their colours and modes.
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Grid Node Operation after Large Nuclear Unit Connection to the Grid
Prokop, Ondřej ; Varmuža, Jan (referee) ; Katovský, Karel (advisor)
The thesis deals with the analysis of the grid node operation after the connection the nuclear unit. The aim of the master´s thesis is to describe the influence of network´s faults to a nuclear unit. Thesis is dealing with three fundamental problems. An influence of short circuits and power imbalance on the synchronous generator of nuclear power plant and its operation of the island network. The thesis is focused especially on the nuclear unit. However, in the case of any failure in the network, it´s necessary to check other units and their protections in the test system because unit failure could cause the disintegration of the power network. For the purposes of the simulation a test system of the power network has been developed. The test system was optimized in the LUG software, which is used to calculate the power network. Transient simulations are performed in the MODES software. Single faults are configured with scenarios. Results are generated into output files. Analysis of influence network´s faults on the synchronous generator of nuclear power plants. The ability of the synchronous generator to restore the primary steady state or hold the new steady state during changes in operating parameters of the network is one of the important parts of the safe and reliable operation of the power network. During the short circuit the damped transient actions occur. With the extension of the short circuit duration, the amplitude of the transient action increases. The risk of the stability loss of a synchronous generator increases. Therefore, the critical clearing time of a short circuit is being defined, which is the time when there is not any loss of stability. Critical clearing time of research generator is sufficient to turn off the short circuit with the help of its protection (the worst case is 0,8 s). For example, by comparison with the hydroelectric power plant, the critical clearing time is much longer. Models of other power plants have been designed with high reliability so in the case of these faults, it doesn’t cause the disintegration of the power network. Creation of island grid is characterized by strong current surges. Units must be resistant to these surges. In the island grid fast changes of the electrical parameters often occurs. Therefore, units must respond to these changes as quickly as possible and in the broadest limits. For this purpose an island operation regulator is being used. In the case of surplus island grid in steam power plants a dump condenser can be used. This is an important ability of steam power plants because the units are able to react quickly to changes of electrical parameters in island grid. The main result of this thesis is the behavior of the nuclear power plant during various faults in the power network. Researched generator of the nuclear power plant is highly stable against faults in the power network based on the findings. The results allow to continue in this topic with real network and real unit of nuclear power plant.
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Analysis of Frequency Measurement and RoCoF in Simulation Programs
Koudelka, Jan ; Máslo, Karel (referee) ; Orságová, Jaroslava (advisor)
The thesis deals with the issue of measurement of frequency and its derivative (RoCoF) in simulation software. The aim of the thesis was to compare results obtained in three different pieces of software (PSS/E, PSCAD, MODES). 2 disturbances were simulated in a grid model IEEE 39 bus system and values of frequency and generator speed were assessed. The results obtained in different software are diverse. This is influenced by method of modelling of synchronous generator and algorithm of calculation of frequency. Findings are important for future investigation of power system transients in simulation software and also point to potencial incorrect assassement of frequency in protective relays.
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Frequency Stability Assessment of Continental Europe Synchronous Area on Equivalent Model
Macejko, Stanislav ; Hába, Tomáš (referee) ; Koudelka, Jan (advisor)
This thesis deals with frequency stability, system disturbances and their dynamic simulation. The aim of the work was to create a single-machine equivalent and single node model for the simulation of the system disturbance from January, 8, 2021 in MODES network simulator. The thesis describes in detail created models and achieved simulation results, which are the frequency deviation waveforms. The simulation results are compared with the actual behaviour of the power system. The thesis further discusses the use of the models and suggests further improvements.
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Model comparison of restoration paths for a system power station in MODES and PSCAD
Peterka, Michal ; Helbich, Jiří (referee) ; Ptáček, Michal (advisor)
The thesis deals with the comparison of two restoration paths in case of the black start in the MODES and PSCAD simulation programs. The aim was to compare the voltage waveforms in individual nodes and the system frequency. At the same time, simulations were compared with a real test. The route models in the MODES program were created earlier and the task was to create the same routes in the PSCAD program using the parameters available from the MODES program. The route models in the PSCAD environment included both the original and the new models of individual elements, which had to be assembled from function blocks. The results of the programs differed slightly, which was caused mainly by the differences of some elements that were used. In the thesis, all the necessary information was stated to make the simulations repeatable.
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Frequency Stability Assessment of Continental Europe Synchronous Area on Equivalent Model
Macejko, Stanislav ; Hába, Tomáš (referee) ; Koudelka, Jan (advisor)
This thesis deals with frequency stability, system disturbances and their dynamic simulation. The aim of the work was to create a single-machine equivalent and single node model for the simulation of the system disturbance from January, 8, 2021 in MODES network simulator. The thesis describes in detail created models and achieved simulation results, which are the frequency deviation waveforms. The simulation results are compared with the actual behaviour of the power system. The thesis further discusses the use of the models and suggests further improvements.
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The comparison of acoustic properties of guitars from the same product line
Trávníčková, Hana ; Indrák, Michal (referee) ; Jirásek, Ondřej (advisor)
This work is dealing with acoustic features of Furch guitars. In theoretical introduction is possible to find an information about basic characteristics of a tone. Following chapter about acoustic guitars is dealing even with mostly used types of woods for their manufacturing. In special chapter are described spectres of signals, LPC analysis, sound radiation of instruments and Chladni figures. Mentioned terms have been evaluated from measurements and are available in practical part of this work also including description of implementation of the measurement. As an output of this work is a comparison of acoustic features of measured guitars, their colours and modes.
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Anti-immigration Attitude in Czech Music: Semiotic Analysis
Růžička, Miroslav ; Podzimek, Jan (advisor) ; Soukup, Martin (referee)
In my diploma thesis, I am reconstructing the anti-immigration attitude in Czech nationalist music production in the year 2016 in the context of the so-called European migration crisis. The sample consists of five selected music videos for nationalist protest songs reacting to the migration crisis and events connected to it. The thesis is based on the theoretical resources of social semiotics and the method of research is the multimodal semiotic analysis, which allows detailed research of the contents of complex communicates like music videos. In the theoretical part, I focus on acquainting the reader to the basics of semiotics, from where I gradually transfer to the school of social semiotics and their theories of modes and multimodality which represent the theoretical background for the analysis in the practical part. Next, I turn to clarifying the progress of the so-called European migration crisis in the years 2015 and 2016 which were crucial for the creation of these nationalist music videos. Also, I justify the choice of the sample and the analyzed themes. The practical part the contains the analysis of the selected music videos using the multimodal semiotic analysis considering three modes - the mode of speech, moving pictures and music. I decode the signs belonging to the pre-set themes....
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Model comparison of restoration paths for a system power station in MODES and PSCAD
Peterka, Michal ; Helbich, Jiří (referee) ; Ptáček, Michal (advisor)
The thesis deals with the comparison of two restoration paths in case of the black start in the MODES and PSCAD simulation programs. The aim was to compare the voltage waveforms in individual nodes and the system frequency. At the same time, simulations were compared with a real test. The route models in the MODES program were created earlier and the task was to create the same routes in the PSCAD program using the parameters available from the MODES program. The route models in the PSCAD environment included both the original and the new models of individual elements, which had to be assembled from function blocks. The results of the programs differed slightly, which was caused mainly by the differences of some elements that were used. In the thesis, all the necessary information was stated to make the simulations repeatable.
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