This master thesis is focused on the design of earthing switch for the indoor three pole generator disconnector from IVEP, a.s. The main task of the theoretical part of the master thesis was mechanical and electrical calculations on the contact system and the design of two variants of earthing switch construction. It has been proposed two variants of earthing switch construction. The first variant included three earthing knives for each pole of earthing switch and the other variant included two earthing knives for each pole. The aim of the practical part of this diploma thesis was to create a model of the earthing switch for generator disconnector, to simulate the heating of the contact system by passing the short-circuit current and to prepare the production documentation. For modeling, calculations and simulations were used Autodesk Inventor 2018, Matlab and Ansys Workbench.

This master thesis is focused on the design of earthing switch for the indoor three pole generator disconnector from IVEP, a.s. The main task of the theoretical part of the master thesis was mechanical and electrical calculations on the contact system and the design of two variants of earthing switch construction. It has been proposed two variants of earthing switch construction. The first variant included three earthing knives for each pole of earthing switch and the other variant included two earthing knives for each pole. The aim of the practical part of this diploma thesis was to create a model of the earthing switch for generator disconnector, to simulate the heating of the contact system by passing the short-circuit current and to prepare the production documentation. For modeling, calculations and simulations were used Autodesk Inventor 2018, Matlab and Ansys Workbench.

High speed applications demands with a need for lower energy consumption lead to designing new types of bearings. In the last decades magnetic bearing, which would be able to obtain passive stable levitation using regular materials at room temperature, has been searched. This has lead to development of electrodynamic bearing based on eddy currents principle. Currently the electrodynamic bearings are still not fully explored and further research is needed. The aim of the work is to describe the theory about modern magnetic bearing, analysis and design of electrodynamic bearing according to given parameters. The finite element method is used for further analysis and evaluate behaviour of its properties.

This thesis deals with design of optimal parameters of a relative displacement sensor, working on the electrodynamics principle. The sensor is based on the voltage induction to the coil placed in changing magnetic field. Thesis is divided into three parts: introductory, theoretical and practical. The introductory part provides basic relationships between displacement, velocity and acceleration sensors. The theoretical part contains physical concepts and describes relationships necessary for calculations and creating a model of permanent magnet in COMSOL Multiphysics. In thesis further presents patent research of electrodynamic sensors. The practical part describes the creation of the permanent magnet model and the subsequent calculation of the induced voltage in the coil in Matlab. A description of laboratory measurements follows, presenting the final comparison of the simulation and measurement results. There were found some differences, which might have been caused by incorrect calculation of the induced voltage. The final part of the thesis presents general recommendations for the design of sensor, resulting from simulations and measurements.

This work deals with the calculation of forces acting on a current carrying path breakers, namely op type BC160 fy Letohrad. There is described the principle of electrodynamic forces and calculation of these forces for different current carrying path. Finally, a simplified model is created by using a circuit breaker simulation program and then forces that arise during the passage of a current are calculated.

The thesis is focused on the calculation of electrodynamic forces that counterwork on moving contacts of compact circuit breaker BL1600 from the company OEZ Letohrad. The thesis is divided into separates chapters that build on themselves. In the introduction the reason why we deal with calculation of dynamic forces and structural arrangement of current carrying path is described. In the following chapter there is a theoretical analysis of electrodynamic forces that conterwork on individual parts of circuit breaker´s element. The third part is devoted to structural arrangement of the circuit breaker BL1600. In this part we can find an example of using the circuit broker Modeion in practice. Two next chaptures deal with adjustment of the model of current carrying path which then serves for the calculation of electrodynamic forces. The rest of the thesis is devoted to my own calculations. These calculations are mainly stationary where we try to find the forces that conterwork on the contacts in a steady current and in a point in time. There are also dynamics calculation when we can watch the forces that counterwork on contacts in a certain time interval. The last chapter is devoted to a stationary calculation of forces that counterwork on the electrical arc which arises while turning the short-circuit current off. The obtained results are evaluated in partial conclusions of this thesis.

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.

The aim of this thesis is to simulate the action of electrodynamic forces on current carrying path and a movable contact of the circuit breaker OEZ Modeion BH 630NE. For the calculation there is used the simulation program Ansys Maxwell. The first part is devoted to theoretical analysis of electromagnetic forces on a conductor in a magnetic field. Further I discuss the constructional design of the circuit breaker itself, especially the current path and the contact mechanism. In the next part there is (with using program Autodesk Inventor) created a simplified 3D model of the current path including an arc chamber. With program Ansys Maxwell then there is performed simulation of the acting of forces in each mode. This is magnetostatic and transient analysis for symmetrical and asymmetrical flow of the fault current. In conclusion the results obtained are evaluated and processed in the tabular way.

Studies of the hyperfine splitting in hydrogen are strongly motivated by the level of accuracy achieved in recent atomic physics experiments, which yield finally model-independent informations about nuclear structure parameters with utmost precision. Considering the current status of the determination of corrections to the hyperfine splitting of the ground state in hydrogen, this thesis provides further improved calculations by taking into account the most recent value for the proton charge radius. Comparing theoretical and experimental data of the hyperfine splitting in hydrogen the proton-size contribution is extracted and a relativistic formula for this contribution is derived in terms of moments of the nuclear charge and magnetization distributions. An iterative scheme for the determination of the Zemach and magnetic radii of the proton is proposed. As a result, the Zemach and magnetic radii are determined and the values are compared with the corresponding ones deduced from data obtained in electron-proton scattering experiments. The extraction of the Zemach radius from a rescaled difference between the hyperfine splitting in hydrogen and in muonium is considered as well. Investigations of forbidden radiative transitions in few-electron ions within ab initio QED provide a most sensitive tool for probing the influence of relativistic electron-correlation and QED corrections to the transition rates. Accordingly, a major part of this thesis is devoted to detailed studies of radiative and interelectronic-interaction effects to the transition probabilities. The renormalized expressions for the corresponding corrections in one- and two-electron ions as well as for ions with one electron over closed shells are derived employing the two-time Green's function method. Numerical results for the correlation corrections to magnetic transition rates in He-like ions are presented. For the first time also the frequency-dependent contribution is calculated, which has to be accounted for preserving gauge invariance. One-loop QED corrections to the magnetic-dipole transition amplitude between the fine-structure levels 2p_{3/2} and 2p_{1/2} are calculated to all orders in \alpha Z. Taking into account consistently relativistic, interelectronic-interaction, and QED corrections to the magnetic-dipole transition amplitude allows for predictions of the lifetimes of the states (1s^2 2s^2 2p)^2P_{3/2} in B-like ions and (1s^2 2s 2p)^3P_2 in Be-like ions with utmost precision. The results of corresponding calculations are compared with experimental data obtained in recent measurements at the Heidelberg EBIT. Finally, for He-like ions with nonzero-spin nuclei the effect of hyperfine quenching on the lifetimes of the 2^3P_{0,2} states is investigated and again compared available experimental data.

Cette thèse porte sur l’identification de systèmes non linéaires représentables en séries de Volterra, et son application à des systèmes sonores. Les séries de Volterra, qui permettent de représenter une large classe de systèmes non linéaires, correspondent à un développement en série organisé par ordre d'homogénéité par rapport à l’entrée: chaque terme homogène est caractérisé par un noyau convolutif dont l’ensemble fournit une "signature complète" du système représenté. Les travaux présentés reposent sur le développement d’une étape préalable de séparation des termes de la série pour améliorer l’identification des noyaux de Volterra. Par rapport aux méthodes déjà existantes de séparation en ordres homogènes, basées sur des relations d’amplitudes entre signaux tests, l'approche adoptée dans cette thèse consiste à exploiter les relations de phase entre signaux afin d'obtenir une méthode robuste. Cela est tout d’abord obtenu de manière abstraite pour le cas de signaux d’excitations complexes. De cette idée, plusieurs méthodes adaptées au cas des signaux réels sont développées. Ceci amène à définir de nouvelles catégories de signaux pour décrire la sortie d’une série de Volterra, regroupant les contributions selon leurs propriétés de phase. Les méthodes de séparation proposées sont testées et appliquées à une pédale d’effet de guitare. Ensuite, des méthodes d’identification spécifiques aux nouveaux types de signaux sont présentées. Enfin, une méthode d’estimation des paramètres d’une représentation d’état à non-linéarités polynomiales est développée. Celle-ci est appliquée à un haut-parleur électrodynamique, dont les caractéristiques non linéaires sont étudiées. / This thesis addresses the identification of nonlinear systems that can be represented with Volterra series, and its application to audio systems. Volterra series give an input-output representation, approximated to within a given error, of any time-invariant continuous nonlinear system with fading memory. Technically, they correspond to a series expansion sorted by homogeneity order with respect to the input: each homogeneous term is characterized by a convolutive kernel whose set provides a "complete signature" of the modelled system. The works presented are based on the development of a preliminary step that consists in separating the series' terms to improve Volterra kernels' identification. Compared to existing homogeneous order separation methods, which are based on amplitude relationships between test signals, the approach chosen in this thesis is to exploit phase relationships between signals to obtain a robust method. This is first obtained in the theoretical case of complex excitation signals. From this idea, several methods suited to the use of real signals are developed. This leads to define new signals categories that describes the output of a Volterra series, sorting nonlinear contributions according to their phase properties. The proposed separation methods are applied and tested on a guitar pedal effect. Then, specific identification methods for the new types of signals are presented Finally, a method for estimating the parameters of a polynomial nonlinear state-space representation is developed. This is applied to an electrodynamic loudspeaker whose nonlinear characteristics are studied.