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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Návrh úprav napájení města Modřice a okolí / Technical modification design of the electrical power systems for Modřice and its surroundings

Šerý, Petr January 2017 (has links)
ABSTRACT This thesis is concerned with a technical modification of design of the electrical power systems for Modřice and its surroundings. The thesis describes a basic theoretical distribution of the electricity network and the distribution network itself. Following chapters are devoted to the development and construction of the HV networks and to the methods and ways of calculating the steady operation of the network. These methods are then used in the computational programs that are presented in the next chapter of this paper. The aim of the practical part of the thesis is to first determine the current state of the network in the given location. Furthermore, several modifications are proposed according to the requirements for increasing the power consumption or connecting the new supply places. The proposed modifications are further assessed for the different operating conditions. The result is a network that is functional, operational and reliable. The whole analysis is carried out in the PAS DAISY Off-line V4 Bizon computing program.
12

Analýza paralelního provozu uzlových oblastí 110 kV TR Krasíkov a TR Neznášov / Analysis of parallel operation of nodal areas of 110 kV Krasikov and Neznasov transformers stations

Kostkan, Petr January 2018 (has links)
Currently, the nodal areas of Neznášov substation and Krasíkov substation, which belong to ČEZd distribution network 110 kV – East, are operand as separate units. In the defined setting, each nodal area comprises of two 400/110 kV transformers. In the case of failure of the transformer T401 or T402, the criterion N-1 for twenty percent of the rated output is not met. Such problem can be solved by parallel operation of nodal areas of Neznášov substation and Krasíkov substation. The principal as well as practical aim of this thesis is to interconnect the bridge operated connection in separated areas into parallel/loop operation of nodal areas (supplied by 400/110 kV transformers). Computing software is used to calculate the steady state and short-circuit conditions in the distribution network 110 kV for separate and parallel operation of mentioned nodal areas. Power flow analysis is aimed at assessment and evaluation of voltage conditions, transformers loading (400/110 kV and 110/vn) as well as 110 kV lines loading. Obtained short-circuit indices is used to examine short-circuit, withstand capability of the 110 kV substation. Finally, benefits as well as drawbacks of the separate and parallel operation are compared and evaluated. If necessary, the technical arrangements are proposed/designed in order to allow parallel operation of nodal areas Neznášov substation and Krasíkov substation.
13

Úprava naftové elektrocentrály pro paralelní chod se sítí / Modification of a diesel generator for parallel operation with the grid

Černý, Martin January 2021 (has links)
This works applies the idea of adjustment an engine-generator, so it is possible to connect an engine-generator, or other type of a generator, to the electricity. Consequently, the machine can transform the power supply without an outage. This work concerns the complex approach, provides the descriptions of particular parts, sensors and active components of a motor-generator and includes the explanation of their function. Further research is focused on designing and drawing a plan with a choice of a control unit for the whole system. Finally, the work deals with the complex implementation and testing the machine in real operation.
14

Denní chod obsahu a aktivity enzymu Rubisco v podmínkách normální a zvýšené koncentrace oxidu uhličitého / Diurnal changes of Rubisco content and its activity under ambient and elevated concentrations of carbon dioxide

Matulková, Zuzana January 2010 (has links)
In this diploma thesis, the diurnal changes of initial and total Rubisco activity and Rubisco enzyme content in beech (Fagus sylvatica) were studied under conditions of ambient (A) CO2 concentration (350 µmol.mol-1) and elevated (E) CO2 concentration (700 µmol.mol-1) during the day. Samples were taken on July 8th (from 10:00 to 21:30), on July 9th (from 04:00 to 12:00) and then on July 22th (from 04:00 to 21:30). The initial and total activity were measured spectrophotometrically and the activation level was calculated from the ratio of initial and total activities. Rubisco enzyme content was determined by SDS-PAGE method and the initial and total specific activity were calculated from the ratio of initial or total activity and Rubisco enzyme content. In our experiment no statistically significant difference was found between Rubisco activities in beeches cultivated under conditions of ambient CO2 concentration and elevated CO2 concentration, so any down-regulation of Rubisco activity did not appear under the influence of ambient CO2 concentration. Diurnal changes of Rubisco activities showed only statistically nonsignificant fluctuation. After daylight no significant increase of total Rubisco activity was observed, which demonstrates the absence or the immaterial effect of CA1P night inhibitor in beech. Intensive fluctuation of the activation level (40–90 %) proves the regulation of photosynthesis during the day via Rubisco enzyme carbamylation. Rubisco enzyme content in beech cultivated under conditions of ambient CO2 concentration was lower than that one in beech cultivated under conditions of elevated CO2 concentration. Then down-regulation of Rubisco enzyme content is presented under conditions of ambient CO2 concentration. Before daylight Rubisco enzyme content showed an indistinctive minimum on the level of statistical significance, during the day only nonrelevant fluctuation was noticed.
15

Návrh provozu sítě 110 kV napájené z transformovny 400/110kV Čebín / Design of the operation of 110 kV power network powered from 400/110 kV Čebín switching station

Kubizňák, Miroslav January 2008 (has links)
Knowlege of elektric power, power dissipation and voltage conditions in every single segments and elektric power system nodes is necessary for operations control and designing of another elektric power system expansion. In this Thesis, we will handle with steady state of system calculation using PAS-DAISY-OFF LINE software, solving various power network configurations and their verification.
16

Ustálený chod a zkratové poměry v síti 110 kV E.ON napájené z rozvodny 110 kV Sokolnice v roce 2011 / Stabilized operation and short - circuit conditions within E.ON 110 kV power network supplied from Sokolnice 110kV switching station, during the period of 2011

Jandora, Jiří January 2011 (has links)
While changing the connection of the power transformators we have to find out if the powered distribution network can accept this change and if it will fulfil the set conditions. Important is to keep the range of permitted voltage on separate distribution points of this network and to find out proportions on separate circuits. This is connected with a circuit load which cannot exceed its limit (transmission capacity). The network is checked against outages of separate circuits (N-1) and we try to find out if other circuits are not overloaded during the transmission of the outaged circuit’s power. We can also suggest various other possible outages. It is also important to find out whether separate distribution points agree with their short-circuit capabilities. Overall we investigate advantages of this circuit. The theoretical part describes the means of calculation of the network functioning and short-circuit conditions. All the calculated results (dispatcher control system Sinaut Spectrum) for the given circuits of power transformators are processed and evaluated in the practical part of the thesis.
17

Návrh rozvoje distribuční sítě 22 kV E.ON v zadané oblasti / Design of the expansion of 22kV distribution network in a specific area

Řehoř, Jiří January 2012 (has links)
The aim of this work is the reconstruction and development of the distribution network of DS to ensure electricity supply in the required quality to existing customers and new customers connecting to the planned industrial zone Šlapanice. The first part deals with the inclusion of a distribution network in power system, its distribution and composition. Subsequently, the work deals with the description of the management of distribution networks, cable and outdoor leadership and their parameters. It also contains guidelines for the design of high voltage networks. The end of the first part is devoted to calculating the steady operation of the network. In the second part, the proposed project using the PAS DAISY Off-line v 4.00 Bizon. Based on the available evidence is developed steady state operation. We found that lines are overloaded and need to be strengthened with regard to the development of industrial zones and adjusting the network to ensure safe and reliable operation. The conclusion focuses on the economic evaluation of proposed alternatives.
18

Ustálený chod a zkratové poměry v síti 110 kV E.ON napájené z rozvodny 110 kV Otrokovice v roce 2012 / Stabilized operation and short-circuit conditions within E.ON 110kV power network supplied from Otrokovice 110kV switching station, during the period of 2012

Kuba, Petr January 2012 (has links)
This thesis deals with steady running and short-circuit conditions in the 110 kV network, E. ON, fed from 110 kV Otrokovice. Substation Otrokovice ensures system transformation from 400 kV to 110 kV system through three transformers. In order to increase reliability of power supply and improved economy is considered to bridge the transition from the operation of two transformers in bridge operations of the three transformers. However, this brings with it significant worsening of short-circuit conditions in the 110 kV network. The task of this work is to evaluate and compare the two variants of operation in terms of steady running and short-circuit conditions in the network at 110 kV and then implement operational and technical measures. The introduction describes the electricity system and its parts. The theoretical part of the paper discusses ways of dealing with steady running and short circuit conditions of long lines. Practical part will deal with applications of knowledge on the network. The conclusion summarizes the most relevant information and the results assessed both variants.
19

Návrh rekonstrukce distribuční sítě 0,4 kV E.ON v zadané oblasti / Proposal of the reconstruction of 0,4 kV distribution network in a specific area

Fojtík, Martin January 2012 (has links)
This Master’s thesis deals with the problem of distribution electrical network with a focus on solving the steady operation of the electrical distribution network for E.ON Brno - Lisen. The calculation is made by using BIZON PAS Off-Line. The first part of thesis is specialized on the distribution of individual LV and MV networks.The second part of thesis is specialized on the general calculation of the steady operation distribution network and describe criteria for the design and evaluation of this network. In the practical part is calculate existing network in selected area in which is located 53 distribution transformers. In the final part is evaluate the status of existing network and perform design optimization and assessment of this network.
20

Ustálený chod a zkratové poměry v síti 110 kV E.ON při paralelním provozu uzlových oblastí R Otrokovice a R Sokolnice / Steady state and short-circuit conditions within E.ON 110 kV power network at parallel operation of nodal areas of Otrokovice substation and Sokolnice substation

Mikulinec, René January 2013 (has links)
This thesis deals with the steady operation and short-circuit conditions in the 110 kV network E.ON in a separate and parallel operation of nodal areas of Otrokovice substation and Sokolnice substation. The theoretical part is devoted to the calculation of steady state high-voltage systems using Newton's iterative method, transient phenomena that may occur in the power system short-circuit calculations and theories. The practical part deals with the actual calculations of steady state and short-circuit conditions in a separate and parallel operation of nodal areas Sokolnice-Otrokovice, which were calculated using the dispatching program. These calculations are then evaluated for possible use of involvement in actual operation. At the end there are suggestions on operational measures in the network 110 kV.

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