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Search results for: przetwornica ac-dc
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Evaluation of organic coatings condition with AFM-based method
PublicationThe paper presents an atomic force microscopy (AFM)-based approach to evaluation of local protective properties of organic coatings. Apart from topography, it provides local ac and dc characteristics of examined coating. The method consists in application of ac voltage perturbation signal between conductive AFM tip and coated metal substrate. The resulting current is used to determine local impedance characteristics. Both impedance...
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Induction Generator with Direct Control and a Limited Number of Measurements on the Side of the Converter Connected to the Power Grid
PublicationThe article presents an induction generator connected to the power grid using the AC/DC/AC converter and LCL coupling filter. Three-level inverters were used in the converter, both from the generator side and the power grid side. The algorithm realizing Pulse Width Modulation (PWM) in inverters has been simplified to the maximum. Control of the induction generator was based on the Direct Field-Oriented Control (DFOC) method. At...
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Assessment of copper surface coverage with corrosion inhibitor using AFM-based local electrical measurements
PublicationThe paper presents a new method of assessment of metal surface coverage with corrosion inhibitor and thus of inhibitor protective performance. It is based on the atomic force microscopy measurement performed in a contact mode. Apart from topography images the proposed approach allows acquisition of local DC maps and local electrical impedance spectra via application of DC bias voltage or AC perturbation signal between the conductive...
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Impedance Studies of Phosphate-iron Glasses Containing Niobium and Titanium
PublicationThe ac and dc conductivity in phosphate-iron-niobate glasses with addition of titanium oxide was investigated as a function of temperature and frequency with the use of impedance spectroscopy. The topography and microstructure of glasses were investigated by the means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and confocal microscopy methods. The obtained results show that all samples are amorphous but they...
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Evolution of the HVDC Link Connecting Offshore Wind Farms to Onshore Power Systems
PublicationThis paper presents an overview of the DC link development and evolution dedicated to HVDC structure for connecting offshore wind power plants to onshore power systems. The growing demand for the green energy has forced investors in power industry to look for resources further out at sea. Hence, the development of power electronics and industrial engineering has enabled offshore wind farms to be situated further from the shore...
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Microstructure and Dielectric Properties of Barium-vanadate Glasses
PublicationThe ac and dc conductivity in barium-vanadate glasses was investigated as a function of temperature and frequency with the use of impedance spectroscopy. The topography and microstructure of glasses were investigated by the means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) methods. The XRD results show that all samples are amorphous but microscopy investigation reveals that glasses with greater amount of V2O5...
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Dynamic characteristics of the proton exchange membrane fuel cell module
PublicationThe paper describes a fuel cell based system and its performance. The system is based on two fuel cell units, DC/DC converter, DC/AC inverter, microprocessor control unit, load unit, bottled hydrogen supply system and a set of measurement instruments. In the study presented in the paper a dynamic response of the proton exchange membrane (PEM) fuel cell system to unit step change load as well as to periodical load changing cycles...
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Bezczujnikowy układ regulacji elektrowni wiatrowej w stanach lotnego startu i osłabiania pola generatora klatkowego
PublicationElektrownie wiatrowe z generatorami indukcyjnymi klatkowymi i przekształtnikami AC-DC-AC posiadają wiele zalet, m.in. szeroki zakres prędkości wiatru oraz możliwość regulacji wzbudzenia generatora w funkcji prędkości obrotowej. Wraz z postępującym zmniejszeniem kosztów przyrządów półprzewodnikowych, układy z generatorami klatkowymi i przekształtnikami dwukierunkowymi będą stanowić coraz większy procent wśród elektrowni wiatrowych...
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Power control system structure of doubly‐fed induction generator connected to current source converter
PublicationThe power control system structures for a doubly-fed generator (DFIG) are proposed. The classical field oriented control and the feedback control with the multi-scalar variables were considered. The generator is working in the AC grid connection mode. The rotor side of the generator is connected to the current source converter (CSC); the stator is directly related to the AC grid. The static feedback linearization using the multi-scalar...
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Bezczujnikowe sterowanie generatorem klatkowym w stanach lotnego startu elektrowni wiatrowej
PublicationElektrownie wiatrowe pracujące na sieć i wyposażone w przekształtniki dwukierunkowe AC-DC-AC, dzięki zastosowaniu generatorówindukcyjnych klatkowych mogą zapewniać efektywne generowanie energii w szerokim zakresie zmian wiatru. W artykule przedstawiono analizęlotnego startu elektrowni wiatrowej z generatorem klatkowym i cyfrowym układem sterowania. Przedstawiono wyniki symulacji lotnego startu generatora klatkowego w układzie ze...
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Modified sliding mode control for seamless integration of P.V. energy in A.C. grid
PublicationSolar energy is a potentially abundant and reliable source of renewable energy. While it can undoubtedly increase grid reliability and efficiency, the inverted voltage generated from PV. sources may introduce distortion into the AC. grid. The proposed control mechanism, modified sliding mode control (MSMC), can seamlessly integrate the inverter output generated by obtaining DC. voltage from the boost converter linked with the PV....
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Zastosowanie termowizji w diagnostyce i badaniach sprzętu elektronicznego
PublicationZaproponowano zastosowanie techniki termowizyjnej do oceny poprawność konstrukcji i działania urządzeń elektronicznych. Technikę termowizyjną zastosowano do badania elementów ochronnych zasilacza AC/DC w czasie standardowych badań odporności na udary oraz do badania modułów GSM pracujących pod kontrolą nadrzędnego programu sterującego i płyty głównej centrali systemu przeciwpożarowego
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Inteligentny transformator dystrybucyjny SN/nn dla sieci Smart Grid o aktywnym udziale prosumentów
PublicationWraz z rozwojem sieci dystrybucyjnych i ich stopniowym przekształcaniem w inteligentne sieci typu Smart Grid będzie rosłoznaczenie i udział sterowanych układów przekształtnikowych mocy stosowanych jako interfejsy pomiędzy źródłami energii a sieciąoraz pomiędzy siecią a odbiorcami. W artykule rozwinięto koncepcję wymiany konwencjonalnych transformatorów dystrybucyjnych50 Hz na inteligentne transformatory dystrybucyjne. Zaproponowano...
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Smart MV/LV distribution transformer for Smart Grid with active prosumer participation
PublicationWraz z rozwojem sieci dystrybucyjnych i ich stopniowym przekształcaniem w inteligentne sieci typu Smart Grid będzie rosłoznaczenie i udział sterowanych układów przekształtnikowych mocy stosowanych jako interfejsy pomiędzy źródłami energii a sieciąoraz pomiędzy siecią a odbiorcami. W artykule rozwinięto koncepcję wymiany konwencjonalnych transformatorów dystrybucyjnych50 Hz na inteligentne transformatory dystrybucyjne. Zaproponowano...
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Implementation of constant component filter in measurements of random telegraph signal noise
PublicationNoise is generated in all semiconductor devices. The intensity of these fluctuations depends on used elements, manufacturing process, operating conditions and device type. The result noise is a superposition of different kinds of fluctuations like thermal noise, generation-recombination noise, 1/f noise, shot noise and Random Telegraph Signal (RTS) noise. The last one, RTS noise is observed as nonstationary impulse fluctuations....
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Modeling of a Quasi-Resonant DC Link Inverter Dedicated to Common-Mode Voltage and Ground Current Reduction
PublicationIn this paper, the modeling methodology of the AC drive system with a Parallel Quasi-Resonant DC Link Inverter (PQRDCLI) is described. A presented modeling approach is an attractive tool used for the effective evaluation of a common-mode (CM) voltage and grounds current reduction methods. Designed models of inverter, induction machine (IM), and cable are simple, thus the methods for parameter extraction are not complicated. Verification...
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Spin-glass behavior in a binary Pr 3 Ir intermetallic compound
PublicationPolycrystalline Pr3Ir was synthesized by arc melting. Its cementite-type crystal structure (Pnma) was confirmed by powder X-ray diffraction and estimated lattice parameters are in agreement with literature. Physical properties were measured by means of the ac and dc magnetic susceptibility, electrical resistivity and heat capacity. Our results indicate spin-glass behavior in Pr3Ir with a freezing temperature Tf = 6.58 K and activation...
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Dual Active Bridge (DAB) DC-DC converter for multilevel propulsion converters for electrical multiple units (EMU)
PublicationSemiconductor power devices made from silicon carbide (SiC) reached a level of technology enabling their widespread use in power converters. Two different approaches to implementation of modern traction converters in electric multiple units (EMU) have been presented in recent years: (i) 3.3-kV SiC MOSFET-based three-level PWM inverter with regenerative braking and (ii) 6.5-kV IGBT-based four-quadrant power electronic traction transformer...
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Dynamiczne wyznaczanie parametrów elektrycznego obwodu szeregowego
PublicationPo załączeniu napięcia na skutek istnienia inercji prąd w obwodzie zaczyna narastać od wartości zerowej do znamionowej. W tym czasie narastają spadki napięć na rezystancjach (impedancjach obwodu) do chwili spełnienia prawa Kirchhoffa. Można utworzyć układ ze sprzężeniem zwrotnym (układ regulacji stałowartościowej bądź nadążnej), który poszukuje parametrów obwodu spełniających prawa Kirchhoffa – elementy nie muszą być liniowe. W...
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Exercise bike powered electric generator for fitness club appliances
PublicationA generator powered by a stationary bicycle for the purposes of generating electricity for fitness club appliances is considered. A generator is connected to a stationary bicycle in such a way as the circular rotation of the front wheel rotates the coils of wires inside the generator between the poles of the magnets inside the generator. The resulting Direct Current is channeled to the attached battery bank and converted into different...
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Multipulse inverter structures with low voltage distortion
PublicationA novel approach to the voltage source inverters (VSI) construction is presented in the paper. The invented inverter structures allow to operate several DC/AC converters in parallel resulting in lower voltage distortions at extremely low switching frequency. The research presented in the paper describes such a parallel operation of the VSI’s which is possible thanks to the use of coupled inductors. The eighteen-pulse three-level...
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Nonlinear and linear impedance of bismuth vanadate ceramics and its relation to structural properties
PublicationThe nonlinear and linear electrical properties, topography, and microstructure of bismuth-vanadate ceramics, were studied. The structurewas observed with the use of X-ray diffraction (XRD), scanning electronmicroscopy (SEM), atomic force microscopy (AFM) and confocal microscopy methods. The obtained results showed that ceramic is porous. Two phase transitionswere determinedwith the use of DSC measurements. The linear and nonlinear ac...
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Paweł Szczepankowski dr hab. inż.
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Elementy analizy RAMS i cyklu życia napędów nowej generacji w układzie e-transformatora realizowanych w technologii SiC do elektrycznych zespołów trakcyjnych
PublicationTransport kolejowy podlega ciągłej presji, aby zwiększać dostępność połączeń i obniżać koszty przejazdów. Konstruktorzy pociągów i przewoźnicy, w odpowiedzi na stawiane oczekiwania, starają się wdrażać pojawiające się na rynku nowe innowacyjne rozwiązania. Europejski program Shift2Rail stawia ambitne cele w stosunku do kluczowych wskaźników wydajności (z ang. KPI - Key Performance Indicators) systemu kolejowego obejmującego infrastrukturę,...
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Investigation of magnetic order in a new intermetallic compound Nd2PtGe3
PublicationIn the present study we report a successful synthesis of the new intermetallic compound Nd2PtGe3 by an arc-melting method. The powder X-ray diffraction analysis indicates that this compound crystallizes in an disordered variant of the AlB2-type structure (space group P6/mmm, no. 191) with lattice parameters a = 4.2455 Å and c = 4. 1933 Å. The compound exhibits a cluster-glass transition below Tf = 2.9 K, characterized through ac...
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Modular multipulse voltage source inverters with integrating coupled reactors
PublicationA novel approach to the voltage source inverters (VSI) construction is presented in the paper. The invented inverter structures allow to operate several DC/AC converters in parallel resulting in lower voltage distortions at extremely low switching frequency. The research presented in the paper describes such a parallel operation of the VSI’s which is possible thanks to the use of coupled inductors. The eighteen-pulse and twenty-four-pulse...
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Jednofazowy falownik napięcia z aktywnym obwodem odsprzęgającym
PublicationZnanym zagadnieniem w jednofazowych falownikach napięcia jest pobieranie ze źródła napięcia stałego składowej przemiennej o częstotliwości dwukrotnie większej od częstotliwości generowanej przez falownik. Jednym z rozwiązań problemu jest stosowanie dużej baterii kondensatorów elektrolitycznych, lecz lepszym sposobem z punktu widzenia niezawodności i gęstości mocy przekształtnika jest stosowanie aktywnych układów odsprzęgania mocy....
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Feedback Control of Doubly-Fed Generator Connected to Current Source Converter
PublicationDoubly-fed induction generator (DFIG) system supplied by current source converter (CSC) is considered in this article. The DFIG can work in two independent modes: AC grid connection and stand-alone mode. The DFIG is connected to the ac grid directly through its stator and the CSC links the rotor side. In this mode, the active and reactive powers of the DFIG must be controlled. This article proposes two control system structures...
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The AC motor voltage and audible noise waveforms in ship’s electrical drive systems with frequency converters
Open Research DataThe presented dataset is part of research focusing on the impact of the ship's electrical drive systems with frequency converters on vibrations and the level of audible noise on ships.
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Testing HIADAC high impedance analyzer in Trento University laboratory on Baunier's RC model using 2 wire probe
Open Research DataThe dataset presents impedance spectrum of Baunier's RC model. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (1 mHz – 100 kHz) was selected in order to test the whole measureement range of the analyzer. In...
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Performance of the PEM fuel cell module. Part 2. Effect of excess ratio and stack temperature
PublicationThe paper describes a fuel cell based system performance under different thermal conditions. The system could be fed with bottled hydrogen or with very high purity hydrogen obtained from reforming of methanol. The system is based on two fuel cell units (1.2 kW each, produced by Ballard Power Systems Inc. and called Nexa), DC/DC converter, DC/AC inverter, microprocessor control unit, load unit, bottled hydrogen supply system and...
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Fault Loop Impedance Measurement in Circuits Fed by UPS and Principle of Safety Protection
PublicationThis paper indicates a significant problem of uncertainty of fault loop impedance (FLI) measurement in circuits powered from uninterruptible power supply (UPS) (double-conversion AC-DC-AC). The correctly determined value of this impedance, related to the short-circuit current disconnection time and to the reference value, is one of the most important elements that determines the approval of an electrical installation and its receivers...
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Experimental test results of the 150kVA 18-pulse diode rectifier with series active power filter
PublicationThe paper presents the control system and selected results of experimental tests of the ac/dc power converter consisting of 18-pulse diode rectifier on the basis of coupled reactors and a serial active power filter. Three configurations of the 150kVA converter were tested experimentally and compared: 18-pulse diode rectifier with and without additional grid reactor and the rectifier integrated with the active power filter. The...
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Zastosowanie termowizji w diagnostyce i badaniach sprzętu elektronicznego
PublicationZaproponowano zastosowanie techniki termowizyjnej do oceny poprawność konstrukcji i działania urządzeń elektronicznych, biorąc pod uwagę krótki czas badań oraz możliwość bezpośredniej oceny uzyskanych wyników. Technikę termowizyjną zastosowano do badania elementów ochronnych zasilacza AC/DC w czasie standardowych badań odporności na udary oraz do badania modułów GSM pracujących pod kontrolą nadrzędnego programu sterującego i płyty...
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Zastosowanie termografii w diagnostyce i badaniach urządzeń elektronicznych
PublicationZaproponowano zastosowanie techniki termowizyjnej do oceny poprawność konstrukcji i działania urządzeń elektronicznych, biorąc pod uwagę krótki czas badań oraz możliwość bezpośredniej oceny uzyskanych wyników. Technikę termowizyjną zastosowano do badania elementów ochronnych zasilacza AC/DC w czasie standardowych badań odporności na udary oraz do badania modułów GSM pracujących pod kontrolą nadrzędnego programu sterującego i płyty...
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Testing HIADAC high impedance analyzer in Trento University laboratory on Baunier's RC model using 3 wire probe
Open Research DataThe dataset presents impedance spectrum of Baunier's RC model. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (1 mHz – 100 kHz) was selected in order to test the whole measureement range of the analyzer. In...
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Testing HIADAC high impedance analyzer in Trento University laboratory on "unknown" object using 2-wire probe
Open Research DataThe dataset presents impedance spectrum of "black-box" object with interesting phase characteristics. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (1 Hz – 100 kHz) was selected in order to test the whole measureement...
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Switching Regulation in the Control of 5-Phase Permanent Magnet Synchronous Motor Fed by 3×5 Direct Matrix Converter
PublicationMatrix converter is an AC-AC direct power converter comprising of an array of bi- directional switches. It does not require an intermediate DC-link and allows sinusoidal output waveforms with varying amplitudes and frequencies. The configuration of these bi- directional switches decides the number of inputs and outputs...
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Measurement methods for assessing insulation condition of underground pipelines
PublicationThe paper discusses the most frequently applied measurement methods for assessing the quality of external insulation along pipelines and detecting defect locations in the protective coating. The quality of coating along a given pipeline section under investigation is assessed by determining unitary resistance of the coating, which is calculated on the basis of measurement results obtained along a pipeline subjected to cathodic...
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Experimental investigation of the weight averaging of pulse frequency modulated sensor output signal
Open Research DataThe research aims to practically verify the results of theoretical analysis and simulations of the efficiency of weight averaging of pulse frequency modulated signal. For this purpose, a suitable test stand was built, and the control software in the LabVIEW environment was prepared. Then, a series of experiments were carried out to process and analyze...
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TRANSFER OF ELECTRIC ENERGY [2023/24]
e-Learning CoursesCourse content: Basic information on the structure of the power system, the major devices (components) for generation, transmission and distribution of electricity. Active and reactive power generation and their sources. Power supply networks. Tasks, structure, parameters. AC and DC transmission of electricity. Equivalent diagrams of the components of the power system. Steady state load flow calculation: currents, voltage,...
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TRANSFER OF ELECTRIC ENERGY [2022/23]
e-Learning CoursesCourse content: Basic information on the structure of the power system, the major devices (components) for generation, transmission and distribution of electricity. Active and reactive power generation and their sources. Power supply networks. Tasks, structure, parameters. AC and DC transmission of electricity. Equivalent diagrams of the components of the power system. Steady state load flow calculation: currents, voltage,...
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TRANSFER OF ELECTRIC ENERGY [2024/25]
e-Learning CoursesCourse content: Basic information on the structure of the power system, the major devices (components) for generation, transmission and distribution of electricity. Active and reactive power generation and their sources. Power supply networks. Tasks, structure, parameters. AC and DC transmission of electricity. Equivalent diagrams of the components of the power system. Steady state load flow calculation: currents, voltage, power,...
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TRANSFER OF ELECTRIC ENERGY [2024/25]
e-Learning CoursesCourse content: Basic information on the structure of the power system, the major devices (components) for generation, transmission and distribution of electricity. Active and reactive power generation and their sources. Power supply networks. Tasks, structure, parameters. AC and DC transmission of electricity. Equivalent diagrams of the components of the power system. Steady state load flow calculation: currents, voltage,...
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Development of an emulation platform for synchronous machine power generation system using a nonlinear functional level model
PublicationThe article presents the Power Hardware in the Loop (PHIL) approach for an autonomous power system analysis based on the synchronous generator model incorporating magnetic saturation effects. The model was prepared in the MATLAB/Simulink environment and then compiled into the C language for the PHIL platform implementation. The 150 kVA bidirectional DC/AC commercial-grade converter was used to emulate the synchronous generator....
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Testing HIADAC high impedance analyzer in cooperation with Road and Bridge Research Institute on polyvinyl coating using 2-wire probe sample 1
Open Research DataThe dataset presents impedance spectrum of polyvinyl coating (code-name PW_2_2_1) sample 1. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (0.1 Hz – 100 kHz) was selected in order to test the whole measureement...
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Testing HIADAC high impedance analyzer in cooperation with Road and Bridge Research Institute on polyvinyl coating using 2-wire probe sample 2
Open Research DataThe dataset presents impedance spectrum of polyvinyl coating (code-name PW_2_2_1) sample 2. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (0.1 Hz – 100 kHz) was selected in order to test the whole measureement...
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Testing HIADAC high impedance analyzer in cooperation with Road and Bridge Research Institute on nano-nickel based coating using 2-wire probe sample 2
Open Research DataThe dataset presents impedance spectrum of nano-nickel based coating sample 2. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The impedance spectrum frequency range (0.1 Hz – 100 kHz) was selected in order to test the whole measureement range of...
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Testing high impedance analyzer in the field on high-voltage line pylon cell 1 exposition 2
Open Research DataThe dataset presents impedance spectrum of anticorrosion coating on high-voltage line pylon presented in the figure below. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The dataset contains comparative measurements with Atlas-Sollich ATLAS98HI analyser....
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Testing high impedance analyzer in the field on high-voltage line pylon cell 1 exposition 1
Open Research DataThe dataset presents impedance spectrum of anticorrosion coating on high-voltage line pylon presented in the figure below. This object was used to test high-impedance analyzer for diagnostic of anticorossion coatings (HIADAC) realized in the frame of Eureka project E!3174. The dataset contains comparative measurements with Atlas-Sollich ATLAS98HI analyser....