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Optimal Design of a Low-Frequency Structural Wiring System
Balák, Dušan ; Slavata, Petr (referee) ; Kadlec, Radim (advisor)
This thesis is concerned with designing and optimizing of a low-frequency structural wiring system in office building. The thesis is divided into two parts, theoretical and practical. Theoretical part is describing factors of designing the low-frequency structural wiring system, with focusing on short-circuits and their consequences on wiring system. Mentioned are optimal economic diameter of electrical cables, purchase and running costs and other factors connected with the optimal designing and protection of electrical devices. In practical part is adjusted, CAD´s system program, assigned a site wiring diagram and allocation of switchboards in the office building. In programs by EATON Elektrotechnika company were developed another parts of project´s documentation. In the Spider program was drew the wiring diagram assigned building and suggested cables and circuit breakers by EATON for correct running in the whole building. In the M-Profil program are designed assigned switchboards and calculated their warming. The motion includes prepared projection documentation, means site wire diagram of the building, schema with evaluations of short-circuits and voltage loss, switchboards design and calculation of their warming.
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Analysis of Static and Dynamic Stresses the Existing 110 kV Substation for Short Circuit Strength Increasing
Balák, Dušan ; Škapa, Milan (referee) ; Orságová, Jaroslava (advisor)
This thesis is concerned with static and dynamic stress calculation of busbar and wire conductors in HV and EHV substations according to standards ČSN EN 60865-1 ed. 2 and ČSN EN 50341-1 ed. 2. Calculations are done in program made in MS Excel with consideration to corporate regulations of energetics. In introduction is described the construction of HV substations and methodical step-by-step computation. Practical evaluation is applied to the substation R110 kV Dluhonice, where has to be checked up sufficient short-circuit resistance because of short-circuit strength increasing. At the end is analysed the influence of the spring structure constant on short-circuit strength forces in substation. Highly significant utility is the founded program for HV substations designations.
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Generating of the fault record for protection and fault indicator testing
Bažata, Petr ; Jinderle, Pavel (referee) ; Topolánek, David (advisor)
The thesis is focused on a presentation of a model creating which is followed by the simulation of running real network with using the compensatory elements to minimize the incurred failures. This thesis is divided into two thematic parts – the first theoretical one deals with the basis structuring of short-circuit faults and more detailed study of ineffective ground connection. Particularly this part attends to the problematic of a network description with extinguishing suppression. Using the compensation minimizes the impact of the failure state. A short-term fixing of a resistor improves the function of the ground-fault protection and helps to detect the outgoing section damaged by the defect. Furthermore the thesis indicates simulation programs, compares them and chooses the most suitable one for the next practical part. This is focused on a simulation of a real network run, together with elements for an effective defect-reduction or easier detection of ground connection. As a simulation of a ground short-circuit is the model in the end of the thesis modified on a network with an effective grounded bundle. Testing of the model correctness and creating a record of a model using the real ground protection settings is also one part of this thesis.
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Calculation of distance protection relay setting for 110kV line.
Bartoš, Petr ; Vaculík, Petr (referee) ; Toman, Petr (advisor)
This work deals with both the calculation of short circuit conditions of 110 kV network in the Czech Republic. This network is divided into two parts, each of which feeds a 400/110 kV substation and the calculation is performed for different locations of a short circuit. The second part deals with the calculation of distance protection settings for one part of this network. The result of this work are the values of network parameters needed to set up distance protection, which protects our individual lines of the network.
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Simulation of phenomena in switchgears
Daševič, Ladislav ; Vávra, Zdeněk (referee) ; Valenta, Jiří (advisor)
Aim of the thesis is to explain the issue of forces acting in circuit breaker caused by magnetic fields induced by short-circuit current. This thesis is focused on force affecting in concrete system of a circuit breaker. The given circuit breaker is made by OEZ Letohrad, the type Modeion BD250. In the thesis the way of creating 3-D model is shown for the purpose of creating numeric simulation by ANSYS 11. The next approach of the thesis is the description of applicating the results for DC and AC current calculations. The noted calculation is made in the programme MATLAB 6.5. The solutions are mentioned at calculations both in the graphic form and numeric specifications. Visualisation was made by using GIF graphic system animation. The individual pictures processing was done in the programme UNLEAD GIF ANIMATOR 5.
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Simulation of Effects of Short-circuit Currents in HV Switching Stations
Tománek, Miloslav ; Buriánek, Jiří (referee) ; Toman, Petr (advisor)
This thesis is engaged in a theoretical calculation of short-circuit currents in electric power system in compliance with the norm ČSN 60909-0 and first of all with calculation of dynamical and thermal effects of short-circuit currents in HV switching stations in accordance with the norm ČSN 60865-1. Next the thesis is engaged in a production of programs for simulation of mechanical effects of short-circuit currents with respect to a dimensioning of constructional elements of switching station and afterwards in a practical simulation of selected parts of the real switching station type „H“ in Slavkov u Brna.
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Steady state and short-circuit conditions within E.ON 110 kV power network at parallel operation of nodal areas of Čebín substation and Sokolnice substation
Múdry, Peter ; Rampl, Martin (referee) ; Blažek, Vladimír (advisor)
In the distribution network 110 kV of E.ON Company there are the nodal areas of Čebin substation and Sokolnice substation which are operated separately at the present time. There is one 400/110 kV transformer for each nodal area. In case of fault on one of these transformers or on busbar in which the set transformer is working, it comes to an outage of electric supply in the set nodal area. This problem has to be solved with help of the parallel operation of nodal areas of Čebín substation and Sokolnice substation. The main and also the practical task of this work is to design the bridge connection appropriate for parallel operation of nodal areas (supply transformers 400/110 kV). With help of a computing program there were made calculations of steady state and short-circuit conditions in distribution network 110 kV for separated and parallel operation of nodal areas. Voltage conditions, load of transformers (400/110 kV and 110/vn kV) and conditions on 110 kV lines are evaluated and controlled as the result of steady state calculations. Based on short-circuit conditions there is controlled the short-circuit resistance of the substations. Finally there are compared advantages and disadvantages of separated and parallel operations of nodal areas. If necessary, technical arrangements required for introduction of parallel operation of nodal areas of Čebín substation and Sokolnice substation will be designed. The theoretical part of the work deals with calculation of steady state with help of iterative methods, namely Newton´s and Gauss-Seidel methods. There are further described the method of calculating short-circuit currents, characteristic values and time behaviours of short-circuit current.
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Localization of short-circuits on single side supplied HV line
Zíka, Jakub ; Jurák, Viktor (referee) ; Topolánek, David (advisor)
This bachelor‘s thesis deals with the localization of unilaterally fed short circuits on high voltage lines. The first part of the bachelor’s thesis deals with the research of the localization of unilaterally fed 1-Phase, 2-Phase and 3-Phase short circuits on the HV lines. Furthermore, individual types of short circuits are described here with suitable procedures for calculating the fault distance and definition of formulas for individual impedance loops. The second part of the bachelor’s thesis focuses on the implementation of these formulas for calculating the distance to the fault location. The input values of voltages and currents were simulated by a simple system model in the PSCAD program. Subsequently, a more detailed sensitivity analysis of individual types of short-circuits was carried out and possible detection of when individual calculation methods fail.
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Design of a 22 kV network in the Lipno area after the integration of the new 110/22 kV transformer station
Žižlavský, Jakub ; Koudelka, Jan (referee) ; Ptáček, Michal (advisor)
This diploma thesis deals with the design of a new 110/22 kV substation in Horní Planá. The substation design addresses, for example, the issue of reducing the load of surrounding power lines from 110/22 kV substations, reducing the size of short-circuit ratios in the surrounding system, reliability and continuity of supply, etc. Furthermore, loads of individual outgoing feeders from the surrounding substations are analyzed, in case they will be connected to a new substation. Following this, the work also addresses the related new decay points of the lines, which are determined by calculation and simulation in the Grizzly program. The simulation results could be used to compare the current load status of individual lines and contribute to the assessment of the possible benefits of both the new substation and the implementation of other modern technologies for faster and more efficient measurement and handling during operating and fault conditions.
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Optimization Of Mesh Network Configuration For Reduction Of Short Circuit Currents
Krcal, Vit
This paper deals with LV mesh network reconfiguration in order to minimize short circuitcurrents. The reconfiguration rests in switching off selected network elements leading to increase ofshort circuit impedances in LV nodes. For optimal configuration, an algorithm of sequential disconnectingof elements is proposed, based on load flow and short circuit calculations. The reconfigurationprocedure is applied to a model of a mesh MV/LV network. Reduction of short circuit currentsin this network is presented, capturing impact of each step of the sequence. Based on the presentedresults, deploying other measures and further development of the proposed algorithm are discussed.
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