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Analysis of Mechanical Stress during Short Circuit in an Air-Insulated MV Switchgear
Bártů, Jan ; Bajánek, Tomáš (referee) ; Orságová, Jaroslava (advisor)
This Master thesis is based on problems of force effects of the magnetic field of short-circuit current. Firstly, I analysed the force action of the three phase busbars during the three-pole short circuit. The analysis was performed in the Ansys Maxwell program and I verified the correctness of the analysis by numerical calculation. The second practical part was executed for ABB company. The main task was to analyse the force effects of the short-circuit current in the HV switchgear with focusing on the arms and contact system of the circuit breaker. The simulations of the following configurations were performed in more details: three configurations of the simplified VD4 circuit breaker, two types of VD4 circuit-breaker contact systems and a linear circuit breaker configuration model. The objective was to calculate the forces acting on the current path of the arms and contact system of the VD4 circuit breaker during the three-phase short-circuit and to simulate the effects of forces on these current parts. For modelling of individual assemblies, calculations and simulations I used: SolidWorks 2014, Ansys Maxwell 16.0 and Ansys Workbench 14.5 programs. With SolidWorks 2014 3D CAD software were modelled simplified assemblies of circuit breakers and contact systems. These systems were imported into the Ansys Maxwell software, where the force effects of the magnetic field of the short-circuit current were calculated. In Ansys Workbench programme was simulated the effect of forces on the current circuit breakers. Moreover, the final deformations of the materials (with respect to the mechanical properties of the structure) were plotted. The analysis of force effects of the magnetic field was performed for the specified static short - circuit current value.
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Evaluation of pressure conditions in the quenching chamber of low-voltage device
Nevrzal, Filip ; Vávra, Daniel (referee) ; Valenta, Jiří (advisor)
In this master’s thesis there is firstly conducted research about pressure measurement. Next there is mathematical description of thermodynamic conditions in used testing chamber by using magnetohydrodynamic and Maxwell equations. Next chapter deals with testing chamber itself, more precisely with function, model and changes done to it. In practical part there are data measured by used sensors, which are also closer described in this chapter. In next chapter there is comparison of reaction times of used sensors and their frequency specters, obtaining using fast Fourier transformation. Second to last chapter introduces very measurement on the real device and in the last chapter these data are analyzed and more closely described.
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Calculation of electrodynamic forces in 250 A circuit breaker
Görig, Michal ; Dohnal, Petr (referee) ; Valenta, Jiří (advisor)
This master’s thesis deals with the calculation of electrodynamic forces breaker BD250NE305. Main tasks in this semester project is to study the theoretical analysis of individual parts specified breakers. Processing theoretical analysis of these forces. Creating a 3D model current path and sheets quenching chamber single phase circuit breaker in Autodesk Inventor Professional 2012. Another challenge is the subsequent export the model into the simulation program ANSYS Maxwell. After simulation, the specified conditions must be processed and the results of the present work is to evaluate.
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Electrical installations in apartment building
Novotný, Jan ; Formánek, Marian (referee) ; Doležalová, Jana (advisor)
This bachelor's thesis deals with electrical wiring in apartment building. The aim is to describe the types of distribution networks, implementation possibilities of service lines, describe the individual parts of the wiring in the building and the principles of their implementation. Further describe basic electrical materials and to explain the design of artificial lighting. In the practical part the information applied to a particular apartment building, together with the calculation of the estimated annual energy consumption of flats. For the apartment building project is created in the form of engineering report and drawings.
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Contact erosion of switchgear under real conditions
Holoubek, Josef ; Bušov, Bohuslav (referee) ; Valenta, Jiří (advisor)
This bachelor thesis is focused on the material loss - contacts erosion during switching process of the switchgears. First part is focused on the switchgears generally, their dividing and functions. Then there is closer look on the contacts of switchgears and what is necessary to be considered during their designing a operating. In this part there is also section devoted to the theory of the contacts erosion including the formulas for material loss calculation, which I found in existing literature. Practical part is focused on the contact system model and the measuring performed on this model. Measuring was also performed on the real switchgears for common use. There is also part devoted to this measuring. In the last part of thesis the analyze of the measured values is performed.
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Testing of Control and Logic Functions of Feeder Terminal
Kaplanová, Klára ; Paar, Martin (referee) ; Orságová, Jaroslava (advisor)
This work occupies itself with an analysis of operational manipulations in the feeder terminal of the distribution system and it considers the configuration of its apparatus equipment with the following configuration of the logical operations for controlling the apparatus in the feeder terminal. Further, this work occupies itself with switching high voltage equipment, their qualities and distribution, with their electrically driven mechanism, including the method of their control. Moreover, the work is aimed at the configuration of the logical operation with the aid of the Boole functions for controlling the feeder terminal apparatus within the CAP 505 software, and at its following testing on the REF 543 terminal from the ABB Company. The aim of the work is theoretical analysis of controlling and operational manipulations in a high voltage distribution system, the following creation and registration of the blocking conditions as well as with their use to create a functional configuration of the feeder terminal of the distribution system and its testing on the demonstration panel which is set with the REF 543 terminal and with further apparatus equipment that simulates the complete high voltage distributor. In the factory configuration the simulation is carried out by the LOGO! module from the Siemens Company. Therefore, our further aim is to design and subsequently to connect the feeder terminal so that the controlling and signaling panel elements could be connected directly to inputs and outputs of REF 543 terminal and could so enable its controlling and checking of the operation conditions. The main aim of the work is to elaborate a detailed description of the functional configuration creation as well as the following REF 543 terminal adjustment for testing the blocking conditions.
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Current distribution and heat losses in the low voltage circuit breakers
Musil, Pavel ; Janda, Marcel (referee) ; Makki, Zbyněk (advisor)
The work is focused on the calculation of decomposing the current and the thermal loss in circuit breakers of low voltage. In the work´s first half, there is a summary of the most frequently used circuit breaker elements with a focus on their constructional layout. The biggest attention is devoted to the circuit breaker marked LPN-16B by the company OEZ. A model of the under current trajectory of this specific element is created in a program Inventor on which the following calculation of decomposing the current and thermal loss was accomplished in a program Ansys. The obtained results are assessed in the conclusion of this work.
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Seismic test of the switching devices on the low voltage
Dubský, Martin ; Mikyska, Kamil (referee) ; Dostál, Lukáš (advisor)
This work analyzes the seismic tests to valid technical starnards. Here is explained the term technical standard and written summary requirements for seismic resistance circuit breakers low voltage. The work includes devices suitable for the purpose and extreme laboratories dealing with seismic tests. The final section provides a draft test station with estimated economic return. Seismic tests are a very important part in the design of not only switching technology. It allows you to simulate the selected mechanical effects which may on the unit during operation or transportation to work and increase its reliability.
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Project Documentation of Electrical Wiring for the Family House in Scope for Realization
Orság, Štěpán ; Janík, Daniel (referee) ; Mastný, Petr (advisor)
The bachelor's thesis is focused on project documentation for a family house in the scope for implementation. The thesis is divided into two parts. The first part presents a theoretical analysis of data distribution and materials for the design of lighting and lightning protection system. The intelligent Loxone system, which is used in a family house project, is also presented in the first part. The second part of the bachelor's thesis is focused on creation of an implementation project, which is consists of text and drawing part. The project includes budget control and risk control. The design of lighting and lightning protection system is also included here. Work drawings of wiring in the house, parts of lightning protection and design of switchboards are integral part of the thesis.
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Simulation of circuit breaker maglatch dynamic behaviour
Konšel, Ladislav ; Dostál, Lukáš (referee) ; Valenta, Jiří (advisor)
This work includes the theory of circuit breaker construction and is focused mainly on overload function. It mainly deals with electronic circuit breakers, i.e. equipped with an electronic trip unit. The work is focused on the part of trip unit - maglatch of trip unit. For the purposes of simulation, the geometric model is created. Maxwell program is used for the simulation. The work describes the options for conditions input which are necessary for simulation. Using the distribution of magnetic field intensity and magnetic flux density in the section of trip unit maglatch is determined by the simulation. Furthermore, the force effects acting on the armature of the maglatch are calculated. Force values and the directions acting on the armature are determined by changing the simulation parameters - shift of the armature and coil current. Simulations are performed both for steady-state and for dynamic simulation – movement of armature is taken into account. The supply source for the maglatch is created by an external circuit.
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