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This paper concerns the effects of electrodynamic forces that act on current paths that are part of high-grade industrial distribution switchgear. This work is composed of experimental and simulation sections. In the experimental section, the short-circuit tests are presented and the occurrence of electrodynamic forces are shown in a visible way. The formation of electrodynamic forces in the current circuits of electrical energy distribution systems is related to the flow of high currents, but mostly it is related to short-circuit currents. In order to highlight these phenomena, the detailed specification of the parameters during tests is displayed. In the simulation section, the physical phenomenon of electrodynamic forces is being captured by employing a detailed real-scale model of switchgear and current paths. Therefore, the authors proposed employment of the FEM (finite element method) in order to obtain values of electrodynamic forces acting on the current paths by executing the detailed 3D coupled simulation. The analysis of the results and aftermath effects of their interactions provided interesting conclusions that concerned the operation of such power distribution layouts in critical short-circuit conditions. [ABSTRACT FROM AUTHOR]

The paper presents a modern method of computer modeling, concerning the low-voltage extinguishing chambers employed in modular apparatuses. The focus was put on presenting the phenomenon of increasing the blow-out, through the use of ferromagnetic plates, dividing the electric arc inside the electrical apparatus. The use of ferromagnetic material for the production of extinguishing chambers results in the distortion of the magnetic field generated by the electric arc. This creates a magnetic force that draws the arc towards the plate area of the extinguishing chamber. The authors presented a modern tool for the analysis of physical phenomena inside the extinguishing chamber. The presented material makes it possible to examine the influence of changes in the geometry and materials of the mentioned components on the process of switching off the current. The applied approach can be used to analyze physical phenomena in devices, not only for alternating current, but also for direct current. Moreover, the model is scaled to the various parameters of these devices. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop a parameterized analytical and FEM (Finite Element Method) model of a switched reluctance motor. The developed analytical model was used to assess the performance of these types of motors, and is determined to be a tool for comparing and evaluating switched reluctance motors of various designs. The aim of the work was also the systematization of knowledge related to the operation, structure and methods of determining the static electromagnetic torque generated by switched reluctance motors. The FEM model (ANSYS) was, also, made in order to verify physical phenomena occurring during operation of these motors. Four laboratory tests were executed as part of the work prototypes of switched reluctance motors built at Warsaw University of Technology. A parameterized analytical model was developed and implemented in MATLAB. The model operation tests were conducted and as a result, the characteristics describing the dependence of the electromagnetic torque as a function of the current and the position of the rotor were obtained. The model was validated by confronting the analytical calculations supported by FEM simulation results with the measurement results. The usefulness of the results obtained with the use of the procured models was assessed. [ABSTRACT FROM AUTHOR]

The purpose of this work is to discuss the tulip contact behavior during mechanical and electrical simulations in a Finite Element Method (FEM) environment using ANSYS and COMSOL software. During the simulations, the full contact movement was analyzed. During the contact movement, the individual behavior of the contact components was taken into consideration. The motion simulation was carried out at different velocities and forces acting on the contact. The obtained results were compared to each other and discussed. Relatively, the angles of the contact surfaces to each other were also changed, which meant that we could conduct a more in-depth analysis. The other approach of simulation research was a field analysis of physical phenomena occurring in the tulip contact. This analysis was performed in COMSOL Multiphysics. Parametric analysis allowed an observation of the electric field in the tulip contact at different contact distances with respect to each other. This work is important in terms of the cost effectiveness for design procedures concerning tulip contacts and fault avoidance, which both result from mechanical and electrical conditions throughout contact exploitation and optimization of the working conditions for the tulip contact. [ABSTRACT FROM AUTHOR]