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Dielectric properties of epoxy with nano particle
Ráček, Tomáš ; Rozsívalová, Zdenka (referee) ; Polsterová, Helena (advisor)
This diploma thesis is focused on the analysis of basic problematics of dielectrics and nanocomposites. It describes the fabrication of experimental samples of nanocomposites from sealing epoxy resin and nanoparticles of titanium dioxide with various weight filling. Further, the thesis deals with measuring and evaluation of dielectric properties of the samples. It examines the influence of weight filling, temperature and frequency of the electric field on volume resistivity, relative permitivity and loss factor.
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Minimizing errors in measuring ultra low currents
Maule, Radek ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
This work describes the methodology of measuring ultra low currents of the order of 10-8-10-14 [A] and the errors that arise during the measurement. This work is focused on electrical conductivity of insulation materials and interfaces electrode - dielectric during charging and discharging of the sample which is located in the ideal workplace.
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Design of high voltage source for electrical ageing of insulating mater
Příborský, Václav ; Rozsívalová, Zdenka (referee) ; Frk, Martin (advisor)
Target of this thesis is analyse problems of dielectric materials ageing and environment characteristic applied by ageing process. Types of electric stress are comparing in this work, when and how they are working and how to eleminate them. Next aim is design the high voltage sinus transformer as source for measuring of electric stress and ageing dielectric materials. There is discuss about computer control and collecting of the output datas. In the end is source testing by practical measurement of some dielectric samples.
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Material prinitng of electroluminiscent panel
Guricová, Patrícia ; Dzik, Petr (referee) ; Vala, Martin (advisor)
This works deals with the preparation of luminescent lamp using screen printing method, characterization of individual layers and the study of spectral properties, influenced by changing printing parameters. In theoretical part are described the principles of electroluminescence as well as the method of preparation of the luminiscent lamp. Experimental part involves optimazing of printing parametres, so the homogenneous light emission is achieved. Furthermore, the influence of the change in the number of layers of active material and dielectric on the light output of the panel at the lowest working voltage is studied. The result of this work is a funcional electroluminescence lamp and an optimazed process for its preparation.
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Application of nanofiller in electroinsulating materials
Mohyla, Petr ; Rozsívalová, Zdenka (referee) ; Frk, Martin (advisor)
This project deals with calculation parts of complex permittivity varnish samples which is filled by nanoparticles of metal oxides. Opening of this project deals with theory of dielectric and effects in dielectric, theory of compounds and expressions in composite systems. Following topic is theory of nanoparticles and nanotechnologies and summarize adjusted results about this branch of knowledge. In practical part of work is include method which was use to make varnish samples filled by nanoparticles, prepare to measurement methods and whole results of measurement. In the end of work is analysis influence of filler particles each filler types to dielectric material and results verified mixture mathematical expressions.
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Study of electrical stress of slot insulations
Jabůrek, Ladislav ; Rozsívalová, Zdenka (referee) ; Frk, Martin (advisor)
This bachelor works deals with electrical effort problems of dielectric materials. The general aim is study of impact alternating electric field of great effort on slot insulation Nomex-Kapton-Nomex. Measurement of loss is realised by dielectric relaxation spectroscopy in frequency domain method. The another aim is apprise of electrical aeging, its causes and incidence on materials. Works deals below dielectric relaxation spectroscopy in time domain and frequency domain, fundamental effect in dielectric and measurement values coherent with electrical aeging.
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Influence of correction factors on the parts of complex permittivity
Hangya, Josef ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
This work consider with monitoring components of complex permittivity at frequency section under the action of alternating electric field. Further factors, affecting the final accuracy of measured values. Object of this experiment is crystalline high-density polystyrene QUINN PS (thickness 2, 3 and 6 millimeters), at which according to the type of electrode system, follow the influence of air gap at the interface electrode - material. The experiment is finally finished with a test report according to standards IEC 250.
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Properties of filled micro- and nanoparticles varnish composites
Novák, Petr ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
The presented work deals with preparation of test samples filled microparticles of mica and nanoparticles of silicon dioxide (SiO2). Monitors the impact of climatic conditions and filler on electrical properties of composite materials. Electrical properties of composite materials are measured by dielectric relaxation spectroscopy. Test samples influence of epoxide resin TSA 220S and polyester resin DOLPHON XL 2102. Varnishes are modified with different weight percentage of nanoparticles of silicon dioxide, or micronized mica. The results of this project are frequency dependencies of parts of complex permittivity and their evaluation.
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Automated workplace for the direct current measurements
Plocr, Radek ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
The present thesis attempts at an overview of DC methods used for diagnosing electrical isolation systems. It investigates the problem of small currents and how to measure them. Part of the thesis deals with building a workstation designed for long-term monitoring of absorbing characteristics of dielectric materials and it also presents a layout of a workstation used for measuring recovery voltage. Both workplaces are computer-automated using the VEE Pro application provided by Hewlett-Packard. Tests were performed on both workstations and the obtained results were processed in a test report as specified under ČSN IEC 93. During the experiment, every effort was made to ensure and monitor the atmospheric conditions of the measuring process.
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Influence of filler particles size on parts of complex permittivity of composite
Mohyla, Petr ; Rozsívalová, Zdenka (referee) ; Frk, Martin (advisor)
This project deals with calculation parts of complex permittivity varnish samples which is filled by ground mica with variety size of particles. Opening of this project deals with theory of dielectric and effects in dielectric. Following topic is theory of compounds and expressions in composite systems. In practical part of work is include method which was use to make varnish samples, their temperature stress and whole results of measurement. In the end of work is influence of filler particles each filler types to dielectric material and including coefficient which include size of filler particles to suitable mathematical expression.
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