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Effects of solar activity in power-distribution grids
Výbošťoková, Tatiana ; Švanda, Michal (advisor) ; Hejda, Pavel (referee)
Eruptive events on the Sun have an impact on immediate cosmic surround- ings of the Earth. Through induction of electric current also affect Earthbound structures such as the electric power distribution networks. Inspired by recent studies we investigate the correlation between the disturbances recorded by the Czech electric-power distributors with the geomagnetic activity represented by the K index. We found that in the case of the datasets recording the disturbances on the power lines with the high and very high voltage levels and disturbances on elec- trical substations, there was a statistically significant increase of failure rates in the periods of maxima of geomagnetic activity compared to the adjacent minima of activity. There are hints that the disturbances are more pronounced shortly after the maxima than shortly before the maxima of activity. Our results provide hints that the geomagnetically induced currents may af- fect the power-grid equipment even in the mid-latitude country in the middle of Europe. A follow-up study that includes the modelling of geomagnetically induced currents is needed to confirm our findings. The second part of our research includes modelling of geoelectric field using one-minute geomagnetic measurements from Intermagnet database. We applied this model to the long-term...
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The influence of solar activity on failure rate of components of Czech power-distribution network
Výbošťoková, Tatiana ; Švanda, Michal (advisor) ; Mošna, Zbyšek (referee)
We analyse the impact of solar activity on Czech power grid. Massive solar flares are responsible for the formation of spaceweather and have a certain impact on technological infrastructures on the Earth and in its surroundings. We elaborated this issue and studied possible effects of spaceweather events on failure rate recorded in Czech power grid. The basis of the practical part is a program that processes the data recording the disturbances on power grid in the Czech Republic obtained by ČEPS (Czech Transmission System Operator) and compared those with the measured values of geomagnetic activity from Budkov station in Šumava by the statistical analysis methods. Our study revealed that there possibly exists some connection between the intensity of solar activity and disturbances in the Czech eletrical power grid. It turns out that the number of faults on the grid during the period of increased solar activity is appreciably higher than in the period of lower solar activity. Our work contributes to the propagation of awareness of disturbances in the Czech electrical power grid that can also arise due to solar activity
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The German Energiewende: Consensual Process ?
Slaba, Martin ; Nigrin, Tomáš (advisor) ; Svobodová, Tereza (referee)
This bachelor thesis examines two very important subparts of the German energy revolution called Energiewende, specifically the level of consensus of the population with the costs of the whole transformation reflected in rising electricity prices and the necessity of expanding and building new power grid sections. The coalition government of SPD and the Greens, which led the state in years 1998-2005 started the whole process by announcing the nuclear phase-out of German Federal Republic and by implementing a renewable energy law (Erneubare Energien Gesetz, EEG) that serves as an instrument through which the renewable energy sources are being subsidized. The law lays all the burden on the final consumer, namely the households and companies, through an electricity surcharge. This surcharge has increased significantly since the year 2000, making the German electricity prices the highest in Europe. Thanks to its massive support, the number of renewable energy sources has risen to a rate, for which the transmission system operators were not prepared. It is obvious that in order to successfully continue with the Energiewende, the power grid has to be expanded. While the consensus of the population with these subparts is crucial, it is useful to know its levels. This thesis comes to the conclusion that...
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Methods for Coloring Nodes in Multigraf
Knotek, Martin ; Kunovský, Jiří (referee) ; Šátek, Václav (advisor)
This thesis deals with algorithms for verticies coloring and their application to the coloring elements of electrical low voltage grid. Result of this thesis is a program, which displays progress of coloring five implemented algorithms on a selected graph. The graph represents electricity distribution network in a city.
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An effect of natural phenomena on electrical devices
Müller, Michal ; Aubrecht, Vladimír (referee) ; Bušov, Bohuslav (advisor)
The Thesis deals with the impact of natural effects on electrical equipment. It describes the various natural effects and shows how it impacts, what it impacts on and what the source of its impact is. The main point of this Thesis is the issue of atmospheric charge (storm and lightning) and the issue of coronal mass ejection (CME). The Thesis shows causally consequences string of geomagnetical field disturbances and resultant power system impacts. There are mentioned historic storm events and power system impacts and description of events in Hydro-Quebec – the most important event. Of this species. At the end there are shows possible way of mitigation power system impacts.
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Differential and Common Mode Conducted Emissions Measurement
Matýsek, Michal ; Soldán, Josef (referee) ; Dřínovský, Jiří (advisor)
This work deals with interfering signals and noises, possibilities of their measurement, their reduction and afterwards with design of LISN. The theoretical part analyzes formation of interfering signals, their types, with possible measuring instruments for each type of these signals and their properties. In framework of practical part LISN for long-term load of 5A, frequency range from 150 kHz to 30 MHz, with possibility to measure symmetrical and asymmetrical noise separately and also with possibility to switch to normal mode of LISN was developed. For better results LISN was realized as two stage LC filter.
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Measurement of Symmetric Cipher on Low Power Devices for Power Grids
Fujdiak, R.
The symmetric ciphers are often used in low power devices for its low requirements. This article provides a measurement of AES-128 cipher, which should be used for secure communication in power grid (smart grid) networks. We are using as low power devices the microcontroller MSP430 from Texas Instruments. These measurements, deal in this article, should help with implementation of the whole concept of encryption. Concretely, it shows the space left for the other algorithms (as for example elliptic curves algorithm for key distribution, communication protocols etc.)
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Narroband PLC model
Sekot, Karel ; Krajsa, Ondřej (referee) ; Mišurec, Jiří (advisor)
This thesis is focused on data communication utilizing low-voltage power distribution lines (PLC). It describes interference in narrowband systems commonly used for remote data collecting, for example. Preamble deals with basic priciples of PLC (signal injecting) and describes the measuring workplace, its wiring and used tools. Following sections define different types and possible sources of interference, operation of the equipment in terms of EMC and other characteristics of the transmission path. The text also analyzes practical interference tests, identifies main parameters affecting data transmision and compares teoretical and practical conclusions.
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