Testowanie cyfrowego terminalu zabezpieczeniowego REF543

This article describes the digital protective relay REF 543 and its testing possibilities. The aim of this work is to verify overcurrent, undervoltage and overvoltage protection functions by indirect method using test equipment CMC 156. Among other things, IED REF 543 will be presented along with its features. The work is a space reserved for the description of the testing methods of protective relay.Artykuł opisuje cyfrowy terminal zabezpieczeniowy REF 543 i możliwość jego testowania. Celem tej pracy jest sprawdzenie funkcji nadprądowej, podnapięciowej i ochrony przed przepięciami metodą pośrednią z wykorzystaniem urządzenia testującego CMC 156. Wśród innych elementów pracy przedstawiono wykorzystanie REF 543 z jego funkcjami. Praca obejmuje opis metod testowania terminalu zabezpieczeniowego

Weryfikacja operacji przekaźnika zabezpieczeniowego odległościowego

This paper describes the possibilities of testing digital protection relay. Consequently, the SIEMENS SIPROTEC 7SA611 distance protection, its protection functions and its use for protection of the line are further characterized. At the end of the article, testing of this distance protection is described along with several variations of Advance distance module testing.W artykule opisano możliwości testowania cyfrowego przekaźnika zabezpieczeniowego. W związku z tym w pracy zostały opisane funkcje ochronne przekaźnika zabezpieczeniowego odległościowego SIEMENS SIPROTEC 7SA611 i wykorzystanie ich do ochrony linii energetycznych. Ostatnia część artykułu zawiera elementy testowania zabezpieczenia odległościowego wraz z kilkoma odmianami w module testowania „Advance distance”

The impact of electromagnetic radiation on the degradation of magnetic ferrofluids

This article deals with magnetic nano-fluids, which are the part of transformer oil ITO 100 and their behavior is influenced by a permanent magnetic field. We performed an IRC analysis in the time domain on the three different samples. Measurements were made before and after radiation of an electromagnetic field. The main objective was to examine changes in the properties of the samples due to the influence of the electromagnetic field. The measurements depend on the orientation of the external magnetic field. This behavior occurs especially during the structuring of the nanoparticles in the sample exposed to the magnetic field. These processes change the polarization of the liquid because the nanoparticles concentration is contained in the fluid

Variation of magnetic fluid deformation related to nanoparticle concentration in steady electric field

Today, it is important to know the behaviour of magnetic fluids applied in the power electrical machines, e.g. in power transformers, when exposed to an electric field. Besides their promising applications in high voltage engineering, they are of increasing interest from designed assembly and pattern formation point of view. The structure of such magnetic fluids is easily controllable by external magnetic fields. However, less attention has been paid to structural phenomena in magnetic fluids induced by electric fields. The core of this paper is dedicated to the experimental observation of a magnetic fluid droplet deformation in a steady electric field. The mutual relation between the deformation parameter and magnetic nanoparticles concentration is analysed. Spatio-temporal analysis of the droplet shape is presented in the paper. The phenomena of the droplet deformation were recorded by a camera. The detailed experimental procedure is presented. The method of deformation parameter calculation based on the linear pixel as the smallest-size unit in digital image is written. Finally, the relation between the deformation parameter and the nanoparticle volume concentration, as well as the time and magnitude of the DC field application are thoroughly evaluated. The results show that the deformation parameter decreases with increasing concentration at constant applied steady electric field but increases with increasing applied steady electric field