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Short - circuit conditions at Sokolnice 110 kV switching station following a direct 400/110 kV transformation
Hajdú, Lukáš ; Paar, Martin (referee) ; Blažek, Vladimír (advisor)
The goal of this bachelor´s thesis is to evaluate short-circuit conditions at the Sokolnice 110kV switching station before and after installation of a T402 transformer – before and after application of a direct 400/110kV transformation. By evaluating these conditions determine whether the originally installed protective elements (power circuit-breakers) are capable of fulfilling the new short-circuit requirements at the switching station. The thesis consists of two parts: the first part introduces the theory required to evaluate the short-circuit conditions at the switching station, while the second part calculates the actual short-circuit currents and power outputs. The methods used for calculation are sequential simplification and symmetrical components.
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Calculation of HV line distance relay setings
Pustowka, Pavel ; Vaculík, Petr (referee) ; Toman, Petr (advisor)
This work is divided into practical and theoretical part. The first part deals with defective states on ehv lines, especially short-circuits and their calculation, further discusses about distance protections and the theory necessary for their correct adjustment. The second part contains practical calculation of short-circuit conditions and adjustment for distance protection on selected part of 110 kV network, belonging to EO.N company. The result of the work are values needed for adjustment all distance protection in entered part of the network.
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Short-circuit Calculation of Local Distribution Network
Byrtus, Jiří ; Paar, Martin (referee) ; Topolánek, David (advisor)
This thesis deals with transient phenomena in the electricity grid - especially with short-circuits. First part describes short-circuit types, reasons for their commencement and also consequences of their functioning. The thesis further shows waveforms of short-circuit currents and its components. A method of calculating short-circuits currents, using the constituent systems and the basic equations for calculating short-circuit impedances are also mentioned here. Relations and methods are based on valid standards of IEC 60909 – 0. The second part indicates the calculation of two-phase and three-phase short-circuit currents for specific network of industrial building. This calculation aims to verify the dimensioning of substations for short-circuit currents after connecting a synchronous generator with given power to the main substation.
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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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