Technicko-ekonomická studie blokových transformátorů VVER1000

The bachelor thesis will deal with the concrete faulty and abnormal conditions of unit transformers of the main production unit VVER1000 experienced by practice, for example, the inter-turn short circuit in the transformer with subsequent deformation of the container, ruptured dry riser pipework of stable fire-fighting equipment (SFFE), the failure of indication of air pressure drop for SFFE and its false activations. The last mentioned topic will discuss the high temperature of the second unit of the unit transformer. In these conditions, it will cope with causes, why the transformers in such situations failed and how these faulty conditions were resolved. They will also explore the possibilities of prevention and protection measures before the occurence of other disorders of the same type and how it is possible to predict these disorders. Along with the analysis of failures will be explored Multitrans monitoring equipment and its operation in practice. The theoretical part will concern the technological mapping of functional units of Temelin Nuclear Power Plant including the main production unit VVER1000, describing the unit transformers and other related equipment. Then, there will be theoretically described the protection of disorders of the aforementioned unit transformers, automation and regular activities of staff serving for safe operation. Finally, the work will deal with optimization of the unit transformers, statistical comparison of the current and proposed state of this facility, incentives to reduce equipment failure rates and improve the overall reliability in operation. The aim of this thesis will be to highlight the possibility of improvement of existing equipment in order to more thoroughly avoid further failures in the future, which happened to block transformers in the past, and to increase the service life not only of transformers, but of all other related elements that together work as a whole. The next aspect of this thesis will be to draw up significant faults and problems to the single document, which can in the future serve as a feedback for solutions to problems that may occur during the next long-term operation of transformers and not only in power stations