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Effects of solar activity in power-distribution grids
Výbošťoková, Tatiana ; Švanda, Michal (advisor)
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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Verification of empirical models of magnetic field around Earth
Kotková, Marie ; Němec, František (advisor) ; Výbošťoková, Tatiana (referee)
The objective of this thesis is to evaluate the accuracy of two frequently used models of magnetic field within Earth's magnetosphere (Tsyganenko 1989, 1996). In order to do this, we use vector magnetic data from four satellites of the Cluster II mission, collected between 2001-2014 and covering almost the whole region of the Earth's inner magne- tosphere at radial distances from 2 to 20 Earth radii. We compare model predictions with spacecraft data and evaluate the spatial dependence of the magnitude differences and angular deviations. Furthermore, we compare model locations of the min-B equator with the locations determined using the four-point measurements, and we study the de- pendence of the respective latitudinal deviations on the level of geomagnetic activity. We show that, although both models are very well correlated with satellite data, the newer model is systematically more accurate. At the same time, we show that the accuracy of both models decreases significantly during the periods of increased geomagnetic activity. 1
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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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