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The aim of this paper is to describe the measurement system and procedure for amount determination and fast Fourier analysis of inrush current which occurs during switching of unbiased transformer on electric grid. This current can reach high amounts and threaten transformer isolation, other transformers and consumers in area. Short introduction in problematic of inrush current phenomena will be presented. In paper the correct measurement settings for inrush current wave form acquisition will be given. Analysis of inrush current waveform in purpose of higher harmonic determination will be given and explained. Usage of gained results in purpose of simulation model evaluation will be explained. The usage of measurement system in purpose of identification of other effects which inrush current can cause will be proposed.

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Development trend in automotive industry is based on development of electric vehicles (EV) and supporting infrastructure. To ensure safety of users and user friendly interfaces, complex systems of power electronics, high voltage and current levels, as well as control systems in real time have priority in research and development. This paper presents an overview of technical solutions and standard procedures related to systems infrastructure for EV power charging, protocols for connections and security systems. Key words: electric vehicle, charging infrastructure, standards procedures, connections

In this paper, we present basics of modeling of complex magnetic circuits in electromagnetic devices for the purpose of didactic considerations. In order to help students better understand the physical issues in a magnetic field, an elementary example of the magnetic field in the coil depending on magnetic core construction has been given. The use of modern software tools for numerical calculation of magnetic fields (FEM) provides easier visualization of the problem and calculation of magnetic circuit parameters for magnetic circuit lumped models by using reluctance. The paper presents an educational scale model of the three-phase three-winding transformers with specially designed coils to provide increased leakage magnetic fluxes and spaces for magnetic field measuring probes