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Search results for: AC motor voltage
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Temperature influences on shear stability of a nanosize plate with piezoelectricity effect
PublicationPurpose The purpose of this paper is to predict the mechanical behavior of a piezoelectric nanoplate under shear stability by taking electric voltage into account in thermal environment. Design/methodology/approach Simplified first-order shear deformation theory has been used as a displacement field. Modified couple stress theory has been applied for considering small-size effects. An analytical solution has been taken into account...
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Effects of Micro-Arc Oxidation Process Parameters on Characteristics of Calcium-Phosphate Containing Oxide Layers on the Selective Laser Melted Ti13Zr13Nb Alloy
PublicationTitania-based films on selective laser melted Ti13Zr13Nb have been formed by micro-arc oxidation (MAO) at different process parameters (voltage, current, processing time) in order to evaluate the impact of MAO process parameters in calcium and phosphate (Ca + P) containing electrolyte on surface characteristic, early-stage bioactivity, nanomechanical properties, and adhesion between the oxide coatings and substrate. The surface...
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Dynamiczna aplikacja Internetowa ASP.NET silnika indukcyjnego jako elementu wirtualnego laboratorium maszyn elektrycznych
PublicationTematem referatu jest dynamiczna aplikacja internetowa, która umożliwia symulację obwodową silnika indukcyjnego trójfazowego Sg 100 L2 z wykorzystaniem interfejsu przeglądarki WWW. Model matematyczny silnika jest zdefiniowany w tzw. osiach naturalnych i sformułowany na podstawie metody energetycznej Lagrange’a. Do implementacji modelu maszyny w aplikacji internetowej wybrano projekt typu Web Forms, który jest składnikiem środowiska...
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A new duty cycles calculation method in pulse width modulation for direct matrix converters based on the shape function concept
PublicationPaper presents a new approach to duty cycle calculation in pulse width modulation for direct matrix converters. The essence of the proposed method is the use of elementary shape function of finite element. The algorithm for calculating the duty cycles was reduced to simple operations on the coordinates of input and output voltage vectors without trigonometric functions.
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Simplified Distribution Grid Modelling for Connection Analyses
PublicationThis paper considers the modelling of medium and low voltage grids for the purpose of connection studies by distribution grid operators. Possible simplifications in grid modelling are discussed, which are acceptable from the viewpoint of the final result. The main driver of the modelling simplification is the MS Excel environment used as the computation platform, and the limitation of time for grid modelling.
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IPMSM rotor position estimator based on analysis of phase current derivatives
PublicationThis paper describes an algorithm for estimation of IPMSM angular rotor position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Algorithm is characterised by a very simple formulae. The calculation of rotor position is performed in every PWM...
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Displacement control in PWK-type pumps
PublicationThe most important, strategic goal however is creation of the variable displacement version of the new pump PWK. Thanks to full discharge of it's commutation mechanism from hydrostatic forces the variable pump can be directly controlled by low-energy actuator like proportional electromagnet or stepping motor. It means that costly and complicated hydraulic servomechanism (applied in all present variable displacement pumps) is no...
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FEX a Fingers Extending eXoskeleton for Rehabilitation and Regaining Mobility
PublicationThis paper presents the design process of an exoskeleton for executing human fingers’ extension movement for the rehabilitation procedures and as an active orthosis purposes. The Fingers Extending eXoskeleton (FEX) is a serial, under-actuated mechanism capable of executing fingers’ extension. The proposed solution is easily adaptable to any finger length or position of the joints. FEX is based on the state-of-art FingerSpine serial...
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Mathematical Models in Design Process of Ship Bow Thrusters
PublicationThe paper describes an application of simulation models for computer-aided design of ship bow thrusters. Generation of simulation models of ship bow thruster requires development and verifying of mathematical models of system component elements. Using the results of simulation the expert system is able to determine, that the rules of classification societies are met. Design procedures and mathematical models are part of an expert...
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Mathematical Models in Design Process of Ship Bow Thrusters
PublicationThe presentation is about an application of simulation models for computer-aided design of ship bow thrusters. Generation of simulation models of ship bow thruster requires development and verifying of mathematical models of system component elements. Using the results of simulation the expert system is able to determine, that the rules of classification societies are met. Design procedures and mathematical models are part of an...
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9-(Trichloroacetylimino)acridine monohydrate
PublicationThe title compound, alternatively called N-acridin-9(10H)-ylidene-2,2,2-trichloroacetamide monohydrate, C15H9Cl3N2O·H2O, crystallizes in space group P21/c with Z = 4. The acridine moieties are arranged in layers, tilted at an angle of 15.20 (4)° relative to the ac plane, while adjacent molecules pack in a head-to-tail manner. Acridine and water molecules form columns along the b axis held in place by a network of hydrogen...
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Transport of alkali metal cations in poly(3,4-ethylenethiophene) films.
PublicationElektrochemicznie otrzymana warstwa kompozytowa złożona z poli(3,4-etyleno-dioksytiofenu) i poli(styrenosulfonianu) podczas polaryzacji ulega odwracalnemu procesowi sorpcji-desorpcji kationów z elektrolitu zewnętrznego. Transportowi jonowemu towarzyszą cząsteczki wody (rozpuszczalnika). Ilość cząsteczek wody przypadająca na jednostkowy kation metali alkalicznych została wyznaczona za pomocą metody elektrochemicznej mikrowagi...
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TECHNIKI CAD W INŻYNIERII ELEKTRYCZNEJ - WYBRANE ZAGADNIENIA
PublicationW pracy przedstawiono różne techniki CAD (ang. Computer Aided Design) wykorzystywane w inżynierii elektrycznej dla potrzeb komputerowego modelowania 3D przetworników elektromechanicznych. Wirtualne modele 3D różnych urządzeń są użyteczne nie tylko przy opracowywaniu dokumentacji technicznej ale są także wykorzystywane w obliczeniach inżynierskich:...
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Analiza ruchowa pojazdów szynowych z uwzględnieniem zmian napięcia na odbieraku prądu
PublicationW artykule zaproponowano metodykę wykonywania analizy ruchowej pojazdów szynowych, która uwzględnia wpływ zmieniającego się napięcia zasilającego pojazd a jego właściwości ruchowe. Wykorzystując model opracowany w programie Simulink wskazano na istotne różnice w czasie przejazdu oraz w wartościach napięcia zasilającego pomiędzy proponowanym sposobem analizy a powszechnie stosowanym podejściem uproszczonym.
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Investigation of solid polymer electrolyte gas sensor with different electrochemical techniques
PublicationIn this work solid polymer electrolyte (SPE) amperometric sulphur dioxide sensor is investigated. Nafion was used as a membrane electrode and 1M sulphuric acid as an internal electrolyte. Sensor response to sulphur dioxide was measured. Besides traditional constant voltage amperometry also different electrochemical techniques were used. Results obtained by these methods are compared.
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Acetate-Induced Disassembly of Spherical Iron Oxide Nanoparticle Clusters into Monodispersed Core−Shell Structures upon Nanoemulsion Fusion
PublicationIt has been long known that the physical encapsulation of oleic acid-capped iron oxide nanoparticles (OA−IONPs) with the etyltrimethylammonium (CTA+) surfactant induces the formation of spherical iron oxide nanoparticle clusters (IONPCs). However, the behavior and functional properties of IONPCs in chemical reactions have been largely neglected and are still not well-understood. Herein, we report an unconventional ligand-exchange...
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Conversion of waste biomass into activated carbon and evaluation of environmental consequences using life cycle assessment
PublicationIn this article, activated carbon was produced from Lantana camara and olive trees by H3PO4 chemical activation. The prepared activated carbons were analyzed by characterizations such as scanning electron microscopy, energy-dispersive X-ray spectroscopy, Brunauer–Emmett–Teller, X-ray diffraction, thermogravimetric analysis, and Fourier transform infrared spectroscopy. H3PO4 is used as an activator agent to create an abundant pore...
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Proposed Amendments to Reactive Energy Billing
PublicationThis paper describes possible amendments to the rules of reactive energy billing in the tariffs in Poland. Modifications in the tariffs to improve their motivational function for distribution system users are identified as the most expedient. New problems arising from distributed generator operations are also indicated. A billing method that can be effectively implemented at the occurrence of distorted voltage and current waveforms...
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Identification of the customer meter assignment to phases in LV grid: Selected issues of UPGRID project realization
PublicationThe paper presents selected issues on the European UPGRID grant implemented by a consortium of companies from seven European states, including from Poland, on the monitoring and control of low voltage grid using measurement pre-registered data by smart AMI meters. The paper focuses on the issue of lack of information on the assignment of communal meters to individual phases.
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СИЛОВОЙ ПРЕОБРАЗОВАТЕЛЬ С АКТИВНЫМ ПОДАВЛЕНИЕМ ВЫСШИХ ГАРМОНИК ДЛЯ СИСТЕМ ЭЛЕКТРОСНАБЖЕНИЯ ЛЕТАТЕЛЬНЫХ АППАРАТОВ (Power converter with active suppression of higher harmonics for aircraft power supply systems)
PublicationПредставлены два алгоритма активной фильтрации для силового преобразователя с активным подавлением высших гармоник. Первый алгоритм основан на дискретном преобразовании Фурье: посредством синтезированной системы управления инвертированные измеренные высшие гармоники напряжения поступают на вход инвертора. Второй метод управления основан на алгоритме с использованием принципов самообучения, что значительно снижает потребность в...
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A Simplified Method of Trend Removal to Determine Noise Observed During a Supercapacitor’s Discharging
PublicationIn this paper, new method of trend removal is proposed. This is a simplified method based on Empirical Mode Decomposition (EMD). The method was applied for voltage time series observed during supercapacitor discharging process. It assured the determination of an additive noise component after subtracting the identified trend component. We analyzed voltage time series observed between the terminals of the supercapacitor when discharged...
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Direct modulation for conventional matrix converters using analytical signals and barycentric coordinates
PublicationThis paper proposes the generalized direct modulation for Conventional Matrix Converters (CMC) using the concept of analytical signals and barycentric coordinates. The paper proposes a novel approach to the Pulse Width Modulation (PWM) duty cycle computing, which allows faster prototyping of direct control algorithms. The explanation of the new idea using analytical considerations demonstrating the principles of direct voltage...
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Ordered TiO2 nanotubes: the effect of preparation parameters on the photocatalytic activity in air purification process
PublicationVertically ordered TiO2 nanotube arrays were synthesized by anodic oxidation of titanium foil in glycerol, ethylene glycol and water-based electrolytes. The effect of electrolyte composition, anodization voltage, ultrasonic treatment and calcination time on the morphology of the resulting thin films, as well as on their photocatalytic activity in toluene removal, used as a model volatile organic compound, was investigated. Toluene,...
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Improved maximum power point tracking algorithms by using numerical analysis techniques for photovoltaic systems
PublicationSolar photovoltaic (PV) panels generate optimal electricity when operating at the maximum power point (MPP). This study introduces a novel MPP tracking algorithm that leverages the numerical prowess of the predictor-corrector method, tailored to accommodate voltage and current fluctuations in PV panels resulting from variable environmental factors like solar irradiation and temperature. This paper delves into the intricate dynamics...
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MPPT and GMPPT Implementation for Buck-Boost Mode Control of quasi-Z-Source Inverter
PublicationThe focus is on the maximum power point tracking implementation for the buck-boost voltage mode control of a single-phase multilevel inverter based on a three-level neutral point clamped quasi-Z-source topology. To utilize shoot-through states only when boost function is needed and avoid it in the buck mode, two different control approaches are required. This work proposes merged control system which provides switching between...
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Risk of power cables insulation failure due to the thermal effect of solar radiation
PublicationLow-voltage, as well as high-voltage power cable lines, are usually buried in the ground. The ampacity of the power cables in the ground mainly depends on the thermal resistivity of the soil, which may vary in a wide range. A common practice in power cable systems performance is to supply them from a pole of an overhead line. If so, a section of the line is located in free air and can be directly exposed to solar radiation. In...
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R&D of satellite pumps and motors with small geometrical displacement supplied with oil and non-flammable liquids
PublicationThe newest construction of satellite motors and self-suction satellite pumps with small geometrical displacement have been described in this article. The characteristics of volumetric and total efficiency of one satellite motor, selected from the series, supplied with oil have been presented. These characteristics have been compared with the orbital motors' characteristics. The remaining specifications of these motors were also...
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Charakterystyka właściwości mechanicznych oraz przewodzących stałych przewodzących kompozytów poliuretanowych
PublicationCelem przeprowadzonych badań było określenie właściwości mechanicznych i przewodzących nowych elektrolitów poliuretanowych. Elastomery poliuretanowe, stanowiące matrycę badanych układów, zsyntezowano przy użyciu 4,4'- diizocyjanianu difenylometanu (MDI), oligo(oksytetrametyleno)diolu (PTMG) i 1,4 butanodiolu (BDO). Sól LiClO4 oraz nanonapełniacz wprowadzono wykorzystując wytłaczarkę dwuślimakową. Przewodnictwo jonowe wyznaczono...
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Charakterystyka stałych przewodzących kompozytów poliuretanowych
PublicationCelem przeprowadzonych badań było określenie właściwości mechanicznych i przewodzących nowych elektrolitów poliuretanowych. Elastomery poliuretanowe, stanowiące matrycę badanych układów, zsyntezowano przy użyciu 4,4'- diizocyjanianu difenylometanu (MDI), oligo(oksytetrametyleno)diolu (PTMG) i 1,4 butanodiolu (BDO). Sól LiClO4 domieszkowano do poliolu a nanonapełniacz wprowadzono podczas przedłużania łańcuchów prepolimeru za pomocą...
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New Method of Non-Linear Electrochemical Impedance Spectroscopy with an Amplitude-Modulated Perturbation Signal
PublicationThe paper presents a new method of non-linear electrochemical impedance spectroscopy (NLEIS), which allows fast and nondestructive evaluation of the corrosion rate and determination of the Tafel coefficients values for a corrosion system under investigation. This method employs amplitude modulation of the ac perturbation signal. The study demonstrated that it was possible to obtain impedance characteristic as a function of the...
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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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Badania eksperymentalne prostownika osiemnastopulsowego o mocy 150 kVA z opcjonalnym szeregowym energetycznym filtrem aktywnym
PublicationW artykule przedstawiono system sterowania oraz wybrane wyniki badań eksperymentalnych przekształtnika AC / DC składającego się z osiemnastopulsowego diodowego prostownika na bazie dławików sprzężonych i szeregowego energetycznego filtra aktywnego. Przebadano i porównano trzy konfiguracje przekształtnika o mocy 150kVA: (1) osiemnastopulsowy prostownik bez dodatkowych elementów, (2) prostownik z dodatkowym dławikiem sieciowym oraz...
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Oddziaływanie przekształtników energoelektronicznych dużej mocy na jakość energii elektrycznej
PublicationW referacie przedstawiono zagadnienia związane z oddziaływaniem układów przekształtnikowych AC/DC na sieć zasilającą poprzez generowanie prądów odkształconych. Przedstawione wyniki badań porównawczych emisji zaburzeń przewodzonych układów prostownikowych klasycznych (diodowych) oraz nowoczesnych (tranzystorowych) wykazują znaczne zwiększenie emisji w zakresie stosowanych częstotliwości modulacji w typowych aplikacjach przemysłowych....
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Novel single-stage buck-boost inverter with unfolding circuit
PublicationA novel solution of a single-stage buck-boost inverter with unfolding circuit at the output stage is presented. The inverter has a wide range of input voltage regulation, minimum passive components and a very flexible control structure. It can be applied for renewable energy systems where high power density is required. Our simulation results confirmed all theoretical statements
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Problemy przyłączania farm wiatrowych do systemu elektroenergetycznego z wykorzystaniem kabli WN
PublicationArtykuł prezentuje problemy, jakie rodzi przyłączanie farm wiatrowych do systemu elektroenergetycznego za pomocą kabli wysokiego napięcia. Autor wskazuje możliwe problemy z kompensacją mocy biernej, w zależności od sposobu przyłączenia dławika kompensacyjnego i nastawień układów regulacji mocy biernej oraz napięcia farmy wiatrowej. Artykuł porusza też zagadnienia zwiększenia strat mocy czynnej powodowanych instalacją dławików kompensacyjnych.
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The Methodology of identifying the place to install shunt compensators in the transmission network
PublicationThis methodology of selection and localization of static com- paper presents pensators in wide network. Proposed method is based on analysis of voltage area power profiles in the nodes of the power grid, and designating locations, In Which Voltages ex- cessively tend to change in time. Practical way of modeling the SVC device in PLANS program you Presented, as well as some example results of research.
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Comprehensive distortion compensation of grid-connected inverter currents
PublicationThe paper presents a comprehensive approach to the compensation of phase current distortion of grid-connected power inverters. Four different sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, voltage fluctuations in the dc link, time delays in the estimation of grid voltages, and the distortion of inverter output voltages due to dead-time effects and related...
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Multifunctional PID Neuro-Controller for Synchronous Generator
PublicationThis paper deals with a PID Neuro-Controller (PIDNC) for synchronous generator system. The controller is based on artificial neural network and adaptive control strategy. It ensures two functions: maintaining the generator voltage at its desired value and damping electromechanical oscillations. The performance of the proposed controller is evaluated on the basis of simulation tests. A comparative study of the results obtained with...
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Sensorless Control of Induction Machine Supplied by Current Source Inverter
PublicationThe paper describes the voltage control technique of induction machines supplied by a current source inverter. The control system is based on proposed new multi-scalar variables, which are named “r.” The control system contains the output filter capacitor's model. In the sensorless control system the Z type backstepping speed observer was applied. The mathematical dependences are confirmed by simulation and experimental research.
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Interconnection of the Customer-Side Resources Using Single Phase VAPF
PublicationThe paper introduces method for utilization of the customer-side generated energy using single phase voltage active power filter. Structure and control method of the power electronics converter has been described and some simulation results are shown to prove usefulness of this arrangements. Proposed application realizes the following functions: power quality improvement, uninterruptible supplying and energy costs reduction.
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Measurement system based on USB Z-Wave controller
PublicationA wireless measurement system based on the Z-Wave standard is presented in this paper. The system is composed of a U SB Z-Stick Gen5 controller connected to a Personal Computer and a Fibaro controller FGRGBWM-441. Operation of the system is controlled by software written in C++ using OpenZWave library. Some metrological aspects of the system are evaluated: accuracy, linearity, resolution and frequency of voltage measurements.
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Feedback Control of Multiphase Induction Machines with Backstepping Technique
PublicationThe paper presents the control possibility of five phase induction machines. In the proposed solution the machine model vector form is not transformed to the (dq)-coordinate system, that is connected to rotor flux vector, but utilizes the stationary system ( αβ ). Moreover, the nonlinear model linearization is based on demonstrated nonlinear variables transformation for i-orthogonal ( αβ )(n) planes. By introducing the backstepping...
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Impact of ITS services on the safety and efficiency of road traffic
PublicationThis paper describes the project entitled: “Impact of the use of Intelligent Transport Systems on the level of road safety” (agreement no. DZP/RID-I-41/7/NCBR/2016), implemented as part of the Road Innovations Development (RID) programme, funded by the National Centre for Research and Development and the General Directorate for National Roads and Motorways (GDDKiA). The project is run by a consortium comprising the Motor Transport...
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Deep learning approach on surface EEG based Brain Computer Interface
PublicationIn this work we analysed the application of con-volutional neural networks in motor imagery classification for the Brain Computer Interface (BCI) purposes. To increase the accuracy of classification we proposed the solution that combines the Common Spatial Pattern (CSP) with convolutional network (ConvNet). The electroencephalography (EEG) is one of the modalities we try to use for controlling the prosthetic arm. Therefor in this...
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Satelitowy agregat pompowy
PublicationW artykule opisano najnowszą konstrukcję satelitowego agregatu pompowego charakteryzującego się tym, że pompa satelitowa jest umieszczona wewnątrz silnika elektrycznego i zasysa ciecz poprzez otwór wydrążony osiowo w wale silnika. Zastosowana w agregacie pompa satelitowa jest nowatorską konstrukcją zawierającą mechanizm satelitowy o odwróconej kinematyce znamienny tym, że planeta (wirnik) oraz płyty kompensacyjne (rozrządu) są...
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Lithium ion insertion into poly(3,4-ethylenedioxythiophene) films from propylene carbonate electrolytes.
PublicationPolimerowa matryca złożona z poli(3,4-etylenodioksytiofenu z poli(styrenosulfonianem) otrzymana została na drodze syntezy elektrochemicznej. Transport jonowy w matrycy polimerowej w kontakcie z węglanem propylenu zawierającym LiClO4 został scharakteryzowany za pomocą metody impedancji ac oraz chronowoltoamperometrii. Wyznaczono przewodność jonową matrycy oraz efektywne współczynniki dyfuzji dla kationu Li+. Wielkości te...
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Determination of pitting corrosion stage of stainless steel by galvanodynamic impedance spectroscopy
PublicationThis paper investigates the methodology for differentiation of multistep process of pitting corrosion of AISI 304 stainless steel in the environment of iron (III) chloride. Measurements were performed using Galvanodynamic Electrochemical Impedance Spectroscopy (GDEIS). Application of this methodology allowed monitoring of natural corrosion process without external current (IDC = 0A) nor potential perturbation of the system. Applied...
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Development of dynamic method for evaluation of inhibition efficiency on the example of 8-hydroxyquinolin
PublicationSelection of a proper inhibitor should be based on the evaluation of its mechanism and effective concentrations. Mechanism of inhibition usually has dynamic character due to changing physicochemical conditions of the environment and corroding metal surface. Most of actually used methods are stationary or contain assumptions which highly influences obtained values. Development of new dynamic method, based on modified EIS, allows...
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Experimental investigations and simulations of the microturbine unit with permanent magnet generator
PublicationIn dispersed power generation, low power devices are used for local combined generating of heat end electric power. There are developing concepts of micropower plants with electric generators driven by steam or gas microturbines. The paper presents the results of an experimental investigations of the microturbine set consists of the turbine with partial admission, permanent magnet generator and three phase AC-to-DC rectifier. The...
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Analytical comparison between capacitor assisted and diode assisted cascaded quasi-z-source inverters
PublicationQuasi-Z falownik z prostym obwodem impedancyjnym jest bardzo interesującym rozwiązaniem topologicznym ze względu na unikalną możliwość jednostopniowego przekształcanie DC/AC w połączeniu z funkcjami obniżania i podwyższania napięcia. W niektórych aplikacjach jego właściwości podwyższające są jednak niewystarczające. Wyższe napięcie wejściowe można uzyskać w wyniku zastosowania w quasi-Z-falownikach kaskadowych obwodów impedancyjnych....