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Search results for: dc-dc converter modeling
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Power Electronic Transformer For Smart Grid Application
PublicationIn this paper the control system of Power Electronic Transformer (PET) for the Smart Grid application is proposed. The structure of PET is based on two Cascaded H-bridge (CHB) converters. The electrical energy is transferred between converters using Dual-Active-Bridges (DAB) and high-frequency transformers. This type of coupling has been used to connect the DC-links of all H-bridges. The proposed control system for PET makes it...
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Ac and dc conductivities in v2o5-p2o5 glasses containing alkaline ions
PublicationWe investigated the ac and dc conductivity in 50V2O5-(50 − x)P2O5-xA2O (A = Li, Na, K) glasses as a function of temperature. The measurements were carried out in the frequency range from 10−4 to 107 Hz. For all compositions, the dc conductivity decreased with the increasing alkali ion content. The decrease in conductivity was more pronounced for larger alkali ions. The ac conductivity exhibited a universal dynamic response: σac...
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Przetwornica rezonansowa LLC AC-DC w układzie półmostka
PublicationW artykule przedstawiono rezultaty prac nad rezonansową przetwornicą AC/DC typu LLC w układzie półmostka o mocy 100W. Układ sterowania przetwornicy został opracowany w oparciu o dedykowany sterownik UCC25600 (Texas Instrumens). W pracy przedstawiono koncepcję przetwornicy oraz porównano właściwości opracowanej przetwornicy z komercyjnie dostępnym układem typu Flyback.
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Analysis of electromagnetic disturbances in DC network of grid connected building-integrated photovoltaic system
PublicationThis paper focuses on conducted electromagnetic interference (EMI) emissions and propagation in the DC network of grid connected building integrated photovoltaic (PV) system. The investigated PV system, consists of ten solar panels, cabling and the grid-connected one phase inverter. The EMI simulation model of the real PV system has been developed with the aid of impedance analyzer measurements of solar panels and the DC network...
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Dynamic variables limitation for backstepping control of induction machine and voltage source converter
PublicationDynamic variables limitation for backstepping control of induction machine and voltage source converter The paper presents the method of control of an induction squirrel-cage machine supplied by a voltage source converter. The presented idea is based on an innovative method of the voltage source converter control, consisting in direct joining of the motor control system with the voltage source rectifier control system. The combined...
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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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Current Source Inverter Fed Drive
PublicationThis book covers three-phase and multiphase (more than three-phase) motor drives including their control and practical problems faced in the field (e.g., adding LC filters in the output of a feeding converter), are considered. The new edition contains links to Matlab®/Simulink models and PowerPoint slides ideal for teaching and understanding the material contained within the book. Readers will also benefit from the inclusion of: A...
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Interline power flow controller - properties and control strategy in dynamic states
PublicationHigh-power electronic converter topologies, in such forms as Unified Power Flow Controllers (UPFC), Static Compensators (STATCOM) and Interline Power Flow Controllers (IPFC), have been used to enhance and optimize the use of transmission facilities, under the concept of a flexible ac transmission system (FACTS). In Europe, the anticipated proliferation of distributed-generation (DG) in the near future, driven by governmental initiatives...
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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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Voltage Source Power Line Conditioner for Applications in Local Supply Systems
PublicationThe paper presents the basic principles of operation of voltage source power line conditioners (VSPLC) as well as their energy and filtration properties. A 4-level cascade based Voltage Source Converter (VSC) is used as a voltage source. The advantages of this topology is relatively simple construction and simple way of balancing DC link voltages. Results of the theoretical and experimental investigations confirm good energetic...
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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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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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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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DC and AC Conductivity, Biosolubility and Thermal Properties of Mg-Doped Na2O–CaO–P2O5 Glasses
PublicationBioactive glasses have recently been extensively used to replace, regenerate, and repair hard tissues in the human body because of their ability to bond with living tissue. In this work, the effects of replacing Na2O with MgO on the electrical, biosolubility, and thermal properties of the target glass 10Na2O–60P2O5–30CaO (in mol%) were investigated. The electrical properties of the glasses were studied with the impedance spectroscopy...
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Comparison of Impedance-Source Networks for Two and Multilevel Buck–Boost Inverter Applications
Publicationmpedance-source networks are an increasingly popular solution in power converter applications, especially in single-stage buck-boost power conversion to avoid additional front-end dc-dc power converters. In the survey papers published, no analytical comparisons of different topologies have been described, which makes it difficult to choose the best option. Thus, the aim of this paper is to present a comprehensive analytical comparison...
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Hybrid high-frequency-SiC and line-frequency-Si based PEBB for MV modular power converters
PublicationIzolowane przekształtniki DC-DC o sterowanym kącie przesunięcia napięć strony pierwotnej i wtórnej są kluczowymi elementami współczesnych modułowych przekształtników energoelektronicznych średniego napięcia (SN). W porównaniu do konwencjonalnych przekształtników SN, przekształtniki modułowe z izolowanymi przetwornicami DC-DC nie wymagają izolacji w postaci wielkogabarytowych transformatorów o częstotliwości sieci. Zastosowanie...
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Reactive deposition of TiNx layers in a DC-magnetron discharge
PublicationTiNx layers have been deposited in 'balanced mode' and 'unbalanced mode' of a reactive DC-magnetron plasma (carrier gas argon, reactive gas nitrogen) under different conditions. Discharge power and reactive gas flow have been varied. The layers have been examined by X-ray photoelectron spectroscopy (XPS), X-ray reflectometry (XR), and spectroscopic ellipsometry (SE). The results of the layer analyses were combined with plasma investigations...
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Optical and chemical characterization of thin TiNx films deposited by DC-magnetron sputtering
PublicationThin titanium nitride (tinx) films were deposited on silicon substrates by means of a reactive dc-magnetron plasma. Layers were synthesized under various conditions of discharge power and nitrogen flows in two operation modes of the magnetron (the so-called "balanced" and "unbalanced" modes). The optical constants of the tinx films were investigated by spectroscopic ellipsometry (se). X-ray photoelectron spectroscopy (xps) was...
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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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Structure and the space vector modulation for a medium-voltage power-electronic-transformer based on two seven-level cascade H-bridge inverters
PublicationThis study presents the structure and the space vector pulse-width modulation (SVPWM) for power electronic transformer (PET) based on two seven-level cascade H-bridge (CHB) inverters. The DC links of CHB inverters are coupled with nine dual-active bridge (DAB) converters with medium-frequency transformers. The DC-link voltages are equalised with two methods – through the control of DAB voltages...
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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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Residual current devices in electric vehicles charging installations
PublicationThe main requirements of national regulations and international standards regarding protection against electric shock in electric vehicle charging installations are presented. The principles of using residual current devices (RCDs) in such installations are discussed. It is pointed out that RCDs are mandatory equipment for safe charging of electric vehicles. It is noted that the standards require the use of RCDs having an appropriate...
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Current harmonic controller in multiple reference frames for series active power filter integrated with 18-pulse diode rectifier
PublicationThe paper presents the control system and selected results of experimental tests of the AC/DC power converter consisting of an 18-pulse diode rectifier based on coupled reactors and a serial active power filter. Proportional integral controllers with decoupling components are implemented in multiple reference frames for selective line current harmonic suppression. The regulator is provided with a backtracking anti-windup mechanism...
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Structure and performance properties of environmentally-friendly biocomposites based on poly(ɛ-caprolactone) modified with copper slag and shale drill cuttings wastes
PublicationThe potential application of two types of industrial wastes, drill cuttings (DC) and copper slag (CS), as silica-rich modifiers of poly(ɛ-caprolactone) (PCL) was investigated. Chemical structure and physical properties of DC and CS fillers were characterized using X-ray diffractometer, X-ray fluorescence spectroscopy, particle size and density measurements. PCL/DC and PCL/CS composites with a variable content of filler (5 to 50...
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MODEL HYBRYDOWEGO ENERGOELEKTRONICZNEGO UKŁADU ZASILANIA WIELOSYSTEMOWYCH ZESPOŁÓW TRAKCYJNYCH (EZT)
PublicationW artykule przedstawiono model układu hybrydowego energoelektronicznego układu zasilania wielosystemowych zespołów trakcyjnych - EZT. Istota proponowanego rozwiązania zawiera się w zastosowaniu do obniżenia napięcia sieci trakcyjnej, zamiast tradycyjnego ciężkiego transformatora trakcyjnego (chłodzonego olejem) - suchego autotransformatora pracującego z częstotliwością sieci kolejowej oraz izolacji galwanicznej od sieci trakcyjnej....
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Low cost set-up for supercapacitors parameters evaluation
PublicationWe propose a use of a power amplifier in the circuit of voltage to current converter (current driver) for supercapacitor charging/discharging in controlled conditions. The current driver is controlled by DAC output of DAQ board and voltage of DUT is measured and a control loop is realized by software. In the circuit the DC current method of evaluation of capacitance and equivalent series...
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Application of commercial supercapacitor modules in autonomic photovoltaic installations
PublicationDynamiczny rozwój technologii i konstrukcji superkondensatorów, napędzany głównie potrzebami przemysłu motoryzacyjnego pozwala na stwierdzenie, że stają się one coraz bardziej realną alternatywą dla konwencjonalnych akumulatorów stosowanych w autonomicznych instalacjach fotowoltaicznych.Za ich stosowaniem przemawiają takie zalety jak: możliwość szybkiego ładowania i rozładowania, wielokrotnie wyższa trwałość, bezobsługowość eksploatacji...
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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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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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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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New Architecture of Solid-State High-Voltage Pulse Generators
PublicationThe application of the nanosecond pulsed electric field (nsPEF) for biomedical treatments has gained more interest in recent decades due to the development of pulsed power technologies which provides the ability to control the electric field dose applied during tests. In this context, the proposed paper describes a new architecture of solid-state high-voltage pulse generators (SSHVPG) designed to generate fully customised sequences...
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Spectroscopic and magnetic studies of highly dispersible superparamagnetic silica coated magnetite nanoparticles
PublicationSuperparamagnetic behavior in aqueously well dispersible magnetite core-shell Fe3O4@SiO2 nanoparticles is presented. The magnetic properties of core-shell nanoparticles were measured with use of the DC, AC magnetometry and EPR spectroscopy. Particles were characterized by HR-TEM and Raman spectroscopy, showing a crystalline magnetic core of 11.5 ± 0.12 nm and an amorphous silica shell of 22 ± 1.5 nm in thickness. The DC, AC magnetic...
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Wpływ konfiguracji elektrod pomiarowych oraz parametrów pomiaru na EDR
PublicationW pracy przebadano wplyw wybranych konfiguracji elektrod na jakość uzyskiwanego sygnału EDR. Analizie poddane zostały również częstotliwość próbkowania sygnału EKG i rozdzielczość przetwornika AC/DC. Optymalną konfiguracją elektrod jest odprowadzenie kończynowe pierwsze. Minimalne parametry układu pomiarowego do uzyskania wysokiej jakości sygnału EDR, to częstotliwość probkowania 2,5kHz oraz 14-bitowy przetwornik AC-DC.
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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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Broadband Compact Single-Layer Magic-T Junction with Separation of DC Signals between All Ports
PublicationA novel structure for a four-port microstrip magic-T junction is presented. The device is composed of microstrip and slotline circuits etched onto two sides of a dielectric substrate. The device is extremely compact and occupies an area more than three times smaller than similar structures recently reported in the literature. The novelty of the device lies in the use of microstrip/slotline transitions for both input ports: summation...
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Hybridized PWM Strategy for Three- and Multiphase Three-Level NPC Inverters
PublicationA simple hybridized pulsewidth modulation (PWM) algorithm for three- and multiphase three-level neutral point clamped (NPC) inverters is proposed. The proposed solution is based on classical space vector PWM (SVPWM) algorithms for two-level inverters but can also be based on sinusoidal PWM with min–max injection. An additional level of output voltage is obtained by modifying the resulting switching patterns taking into account...
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A New Three-Dimensional Space Vector Modulation for Multilevel Four-Leg Converters Based on the Shape Functions of Tetrahedral Element
PublicationThe paper proposes a new three-dimensional space vector pulse-width modulation (3D-SVPWM) algorithm for multilevel four-leg converters. The proposed PWM duty cycle calculation is based on the shape functions of the threedimensional tetrahedral finite elements. The algorithm ensures synthesis of accurate and undistorted output voltages even under significant imbalance or ripple in the DC-link voltages. At the same time, the algorithm...
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Superconductivity and itinerant ferromagnetism of Y9Co7 probed by ac susceptibility
PublicationThe ac magnetic susceptibility of a single crystal sample of the compound Y9Co7 has been measured in applied dc fields ranging from 0–6.7 kOe by utilizing a tunnel diode resonator circuit. In agreement with previous measurements on this material, a superconducting transition has been observed to occur at TSC ≈ 2.5 K. A broad maximum has been observed in the zero field susceptibility measurements from 2.5 K < T < 8 K and its behavior...
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Multi-transformer primary-side regulated flyback converter for supplying isolated IGBT and MOSFET drivers
PublicationThis paper presents primary-side voltage regulated multi-transformer quasi-resonant flyback converter (MTFC) for supplying isolated power switch drivers. The proposed topology offers distinct advantages over frequently used flyback converter possessing one high frequency transformer with isolated multiple outputs. Particularly, when a large number of separate dc supply units is required, then MTFC enables improved regular distribution...
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Komputerowe szacowanie zaburzeń elektromagnetycznych
PublicationPrzedstawiono symulacyjne badania porównawcze w zakresie kompatybilności elektromagnetycznej EMC modelu obwodowego przetwornicy DC-DC podwyższającej napięcie. Zbadano wrażliwość uzyskanego modelu na kolejne uproszczenia jego postaci, w ten sposób otrzymując zredukowany, równoważny model do oszacowania charakterystyki widma zaburzeń EMI na sieci sztucznej. Taki model zrealizowano w symulatorze TCad i porównano zgodność wyników symulacji...
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High Performance Control of AC Drives with Matlab/ Simulink
PublicationExplore this indispensable update to a popular graduate text on electric drive techniques and the latest converters used in industry. The Second Edition of High Performance Control of AC Drives with Matlab®/Simulink delivers an updated and thorough overview of topics central to the understanding of AC motor drive systems. The book includes new material on medium voltage drives, covering state-of-the-art technologies and challenges...
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Simulation Studies of Control Systems for Doubly Fed Induction Generator Supplied by the Current Source Converter
PublicationThe control system for a Doubly Fed Induction Generator (DFIG) supplied by a grid-connected Current Source Converter (CSC) is presented in this paper. Nonlinear transformation of DFIG model to the multi-scalar form is proposed. The nonlinear control strategy of active and reactive power of DFIG is realized by feedback linearization. In the proposed control scheme, the DFIG model and CSI parameters are included. Two Proportional-Integral...
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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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Changes on the Surface of the SiO2/C Composite, Leading to the Formation of Conductive Carbon Structures with Complex Nature of DC Conductivity
PublicationSol–gel layers have been the subject of many studies in recent decades. However, very little information exists about layers in which carbon structures are developed in situ. Using the spin-coating method, we obtained thin iron-doped SiO2/C composite films. The results of Raman spectroscopy showed that our samples consisted of graphitic forms and polymers. The latter’s contribution decreases with rising temperature. FTIR and EDS...
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Różne subpopulacje komórek dendrytycznych oraz sposoby regulowania ich aktywności
PublicationOpisano komórki dendrytyczne (DC), stanowiące złożoną, heterogenną populację leukocytów wywierającą różnorodny efekt na funkcjonowanie systemu odpornościowego.
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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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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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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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Power electronic transformer based on cascaded H-bridge converter
PublicationIn this paper the control strategy of power electronic transformer (PET) is proposed. The analyzed structure of PET uses two seven-level cascaded H-bridge (CHB) rectifiers. The electrical power of PET is transferred between DC-links of CHB converters using dual-active-bridges (DABs) and low voltage high frequency transformers. The roposed solution allows for controlling the active and reactive power with a low level of harmonic...