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Search results for: HIGH-POWER DRIVES
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Enabling a Stable High-Power Lithium-Bromine Flow Battery Using Task-Specific Ionic Liquids
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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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Magnetic and capacitive couplings influence on power and energy measurement in double circuit high voltage overhead transmission line
PublicationThe paper discusses influence of magnetic and capacitive couplings on power and energy measurement in case of double circuit high voltage overhead transmission line. There are presented and discussed various factors influencing the power flow among the line‟s circuits. Mathematical model based calculations results are compared to the real transmission line measurements.
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Analysis of possible application of high-temperature nuclear reactors to contemporary large-output steam power plants on ships
PublicationThis paper is aimed at analysis of possible application of helium to cooling high-temperature nuclear reactor to be used for generating steam in contemporary ship steam-turbine power plants of a large output with taking into account in particular variable operational parameters. In the first part of the paper types of contemporary ship power plants are presented. Features of today applied PWR reactors and proposed HTR reactors...
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Comparison analysis of selected nuclear power plants supplied with helium from high-temperature gas-cooled reactor
PublicationThe article presents results of efficiency calculations for two 560 MW nuclear cycles with high-temperature gas-cooled reactor (HTGR). An assumption was made that systems of this type can be used in so-called marine nuclear power plants. The first analysed system is the nuclear steam power plant. For the steam cycle, the efficiency calculations were performed with the code DIAGAR, which is dedicated for analysing this type of systems....
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Influence of reactive oxygen species during deposition of iron oxide films by high power impulse magnetron sputtering.
PublicationIron oxide films were deposited using high power impulse magnetron sputtering (HiPIMS) of an iron cathode in an argon/oxygen gas mixture at different gas pressures (0.5~Pa, 1.5~Pa, and 5.0~Pa). The HiPIMS system was operated at a repetition frequency $f = 100$~Hz with a duty cycle of 1~\%. A main goal is a comparison of film growth during conventional and electron cyclotron wave resonance-assisted HiPIMS. The deposition plasma...
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DEPO: A dynamic energy‐performance optimizer tool for automatic power capping for energy efficient high‐performance computing
PublicationIn the article we propose an automatic power capping software tool DEPO that allows one to perform runtime optimization of performance and energy related metrics. For an assumed application model with an initialization phase followed by a running phase with uniform compute and memory intensity, the tool performs automatic tuning engaging one of the two exploration algorithms—linear search (LS) and golden section search (GSS), finds...
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Mechanical and Thermal Properties of W-Ta-B Coatings Deposited by High-Power Impulse Magnetron Sputtering (HiPIMS)
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Physical properties of homogeneous TiO2films prepared by high power impulse magnetron sputtering as a function of crystallographic phase and nanostructure
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Comparative analysis of thermodynamic cycles of selected nuclear ship power plants with high-temperature helium-cooled nuclear reactor
PublicationThis paper presents a comparative analysis of thermodynamic cycles of two ship power plant systems with a high-temperature helium- cooled nuclear reactor. The first of them is a gas system with recuperator , in which classical gas chamber is substituted for a HTGR reactor (High Temperature Gas-cooled Reactor) . The second of the considered cycles is a combined gas-steam system where working medium flux from gas turbine outlet...
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Improving the Performance of a Graphite Foil/Polyaniline Electrode Material by a Thin PEDOT:PSS Layer for Application in Flexible, High Power Supercapacitors
PublicationIn this study, we present a novel strategy for enhancing polyaniline stability and thus obtaining an electrode material with practical application in supercapacitors. A promising (graphite foil/polyaniline/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) GF/PANI/PEDOT:PSS) electrode material was characterized and used in the construction of a symmetric supercapacitor that provides an outstanding high power density. For this...
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Optimization of hybrid parallel application execution in heterogeneous high performance computing systems considering execution time and power consumption
PublicationMany important computational problems require utilization of high performance computing (HPC) systems that consist of multi-level structures combining higher and higher numbers of devices with various characteristics. Utilizing full power of such systems requires programming parallel applications that are hybrid in two meanings: they can utilize parallelism on multiple levels at the same time and combine together programming interfaces...
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Physical properties of homogeneous TiO2 films prepared by high power impulse magnetron sputtering as a function of crystallographic phase and nanostructure
PublicationOptical, photo-electrochemical, crystallographic and morphological properties of TiO2 thin films prepared by high power impulse magnetron sputtering at low substrate temperatures (<65 ◦C) without post-deposition thermal annealing are studied. The film composition-anatase, rutile or amorphous TiO2-is adjusted by the pressure (p ∼ 0.75-15 Pa) in the deposition chamber. The different crystallographic phases were determined with grazing...
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Plasma diagnostics of low pressure high power impulse magnetron sputtering assisted by electron cyclotron wave resonance plasma
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The Finite Elements Method application to assesment the impact of turbulence generated by wind turbines on their lacation inclose proximity of overhead high voltage power transmissionlines
PublicationThe paper presents selected aspects of construction of wind turbines location concerning aerodynamic impact on power lines. Reaserch is based on the source data concerning the aerodynamic impact of a wind farm consisting of 8 turbines and 400 kV power line, an analysis of the possibility of wind farm locating in the immediate vicinity of the line was carried out. There are serious problems with locating higher capacity wind farms...
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Optical and structural properties of polycrystalline CVD diamond films grown on fused silica optical fibres pre-treated by high-power sonication seeding
PublicationIn this paper, the growth of polycrystalline chemical vapour deposition (CVD) diamond thin films on fused silica optical fibres has been investigated. The research results show that the effective substrate seeding process can lower defect nucleation, and it simultaneously increases surface encapsulation. However, the growth process on glass requires high seeding density. The effects of suspension type and ultrasonic power were...
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Highly Oriented Zirconium Nitride and Oxynitride Coatings Deposited via High‐Power Impulse Magnetron Sputtering: Crystal‐Facet‐Driven Corrosion Behavior in Domestic Wastewater
PublicationHerein, highly crystalline ZrxNy and ZrxNyOz coatings are achieved by the deposition via high‐power impulse magnetron sputtering. Various N2 and N2/O2 gas mixtures with argon are investigated. The chemical composition and, as a result, mechanical properties of the deposited layer can be tailored along with morphological and crystallographic structural changes. The corrosion resistance behavior is studied by potentiodynamic measurements...
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Derivation of motor mean phase currents in PMSM drives operating with low switching-to-fundamental frequency ratio
PublicationPulse width modulation (PWM) of inverter output voltage causes the waveforms of motor phase cur-rents to consist of distinctive ripples. In order to provide suitable feedback for the motor current con-trollers, the mean value must be extracted from the currents’ waveforms in every PWM cycle. A com-mon solution to derive the mean phase currents is to sample their value at the midpoint of a symmetrical PWM cycle. Using an assumption...
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Open-Phase Fault Detection Method for Sensorless Five-Phase Induction Motor Drives with an Inverter Output Filter
PublicationThe paper presents the sensorless five-phase induction motor drive implementation with an inverter output filter with third harmonic injection. For the sensorless operation, the required observers are presented for the first and third harmonics with consideration of the inverter output filter. Moreover, the interaction of the observers and the control system is capable to handle a deactivation of one or two phases, which improves...
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Cavitation resistance of OH18N9 steel alloyed with vaidus amount of TiC or Mn by means of laser beam. XIV International Symposium on Gas Flow, Chemical Lasers and High Power Lasers.
PublicationPrzedstawiono badania odporności kawitacyjnej stali OH18N9T po laserowym stopowaniu jej powierzchni węglikiem TiC oraz manganem. Wykazano, że wzbogacenie obrabianej stali manganem powoduje przemiany fazowe pod wpływem działania obciążeń kawitacyjnych, co przyczynia się do wzrostu odporności kawitacyjnej. Wzmacnianie stali węglikiem TiC powoduje natomiast zanik zdolności stali do wzmacniania odkształceniowego.
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High frequency test measurements on physical model of power transformer with use of FRAX analyzer Streszczenie. W niniejszym artykule przedstawiono pomiary testowe SFRA wykonane na modelu fizycznym transformatora elektroenergetycznego
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Medium-Voltage Drives: Challenges and existing technology
PublicationThe article presents an overview of state-of-art solutions, advances, and design and research trends in medium-voltage (MV) drive technologies - and also discusses the challenges and requirements associated with the use of such drives. The choice and deployment of MV drives in industries are associated with numerous requirements related to the front-end converter (grid side) and inverter (machine side). The focus is on solutions...
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Start-up of a power unit of a thermal power plant auxiliary systems with supply from a hydropower plant
PublicationThis article discusses the issues related to a power unit of a thermal power plant start-up with the use of a hydropower plant. Hydropower plant can supply and will enable start-up of auxiliary equipment in a power unit of a thermal power plant. Due to high capacity of auxiliary drives, start-up of auxiliaries in a thermal power plant after blackout (and boiler shutdown) is not possible from emergency energy sources in the power...
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Model-Free Controller Tuning Based on DFT Processing: Application to Induction Motor Drives
PublicationIn this paper, we present a new approach based on discrete Fourier transform (DFT) analysis for controller tuning of the closed-loop system with unknown plant. The DFT analysis is used to process the closed-loop measurements collected online to derive the frequency response of an initial closed-loop system that does not provide a good performance. Based on the closed-loop frequency response data, we propose two methods for tuning PID...
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ANALYSIS OF ENERGY EFFICIENCY IN ELECTRIC DRIVES
PublicationIn this paper energy efficiency in electric drives is analysed. This factor strongly depends on energy parameters - efficiency n and power factor k (in special case cos fi)
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Pulse-Width Modulation of Power Electronic DC–AC Converter
PublicationThe 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 in the industrial drive system, as well as their components, and control, current source inverter-based drives, PWM techniques for...
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Medium voltage drives - challenges and requirements
PublicationThe design and application of medium voltage (MV) drives are associated with different requirements related to the line side and motor side of the drive. This paper presents a brief review of the existing challenges and requirements for employing medium voltage drives in various industries. Line side, motor side, and converterproblems and requirements are described. The aim of the paper is to review the existing problems to allow...
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Advances in CSI-fed induction motor drives
PublicationThe application of current source inverters (CSI)in induction motor (IM) drives offers a number of advantages,including: voltage boosting capability, natural shoot-throughshort-circuit protection and generation of sinusoidal voltages.The exact generation of sinusoidal voltages is possible thanks tothanks to the effect of the output ac filter capacitors and mayimprove the accuracy of sensorless IM control. The eliminationof high...
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Worm Gear Drives with Improved Kinematic Accuracy
PublicationThis paper presents the fundamentals of the design and applications of new worm gear drive solutions, which enable the minimisation of backlash and are characterised by higher kinematic accuracy. Different types of worm surfaces are briefly outlined. Technological problems concerning the principles of achieving a high degree of precision in machining are also described. Special attention is paid to the shaping of conical helical...
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Electric shock hazard in circuits with variable-speed drives
PublicationThe conventional approach to electrical safety under fault condition in typical power systems considers earth fault currents of sinusoidal waveform and frequency of 50/60 Hz. However, in circuits with variable-speed drives, there is earth fault current flow with harmonics, and these harmonics influence the threshold of ventricular fibrillation. The paper presents earth fault current waveforms in circuits with variable-speed drives...
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Variable Speed AC Drives with Inverter Output Filters
PublicationThe advance of variable speed drives systems (VSDs) engineering highlights the need of specific technical guidance provision by electrical machines and drives manufacturers, so that such applications can be properly designed to present advantages in terms of both energy efficiency and expenditure. This book presents problems and solutions related to inverter-fed electrical motors. Practically orientated, the book describes the...
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On the production of electricity in Poland using a geothermal binary power plant - A thermodynamic overview - Part I
PublicationPoland has a significant potential of geothermal energy. However, the high-temperature sources that are needed to drive power plants are found in relatively few places. Therefore, the objective of this paper is to consider any location in the northern part of Poland as a possible place to build a binary power plant. A scientific research was confirmed the existence of an elevated temperature gradient in this region. The hot rocks...
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Asymmetrical Modes in Polyphase Motors and Drives
PublicationThe effect of power supply and/or motor asymmetry on the phase-load distribution and the ripple of electromagnetic torque in a polyphase drive is studied by the method of symmetrical components. It is shown that the presence of asymmetry causes the mapping of all harmonics in the supply voltage into all planes of symmetrical components and eliminates the possibility of independent control of harmonics. The dynamic model of a five-phase...
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Faults and Fault Detection Methods in Electric Drives
PublicationThe chapter presents a review of faults and fault detection methods in electric drives. Typical faults are presented that arises for the induction motor, which is valued in the industry for its robust construction and cost-effective production. Moreover, a summary is presented of detectable faults in conjunction with the required physical information that allow a detection of specific faults. In order to address faults of a complete...
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Double Fed Induction Machine Drives
PublicationContents of the Chapter 22:Machine model.Properties of the DFM.Steady state machine operation.Control rules and decoupled control.Decoupling based on MM machine model.Decoupling based on vector model.Decoupling based on rotor current equation.Overall control system.Control system based on MM model.Control system based on vector model.Estimation of variables.Calculation of the angle between stator and rotor.Remarks about digital...
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Series Passive Compensation of Common Mode Voltage in Multilevel Inverter Drives
PublicationThis paper presents an approach to the problem of a magnetic saturation of CM chokes that accompanies the method of passive compensation of a common mode (CM) voltage in an inverter drive system. Measurements have been provided in a drive system including multilevel inverters and the filter having sinusoidal output voltages and zero CM voltage. The theoretical analysis and experimental results show that the problem with magnetic...
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Experimental evaluation of the PLC-controlled drives properties.
PublicationPrzedstawiono strukturę stanowiska laboratoryjnego do testów oprogramowania PLC do sterowania napędami oraz do prowadzenia eksperymentalnych prób takich napędów. Omówiono zasady prowadzenia testów oprogramowania przed i w trakcie uruchamiania napędu. Przedstawiono przykładowe rezultaty doświadczeń.
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Possibility of Fault Detection in Sensorless Electric Drives
PublicationThe work presents a fault detection method for an induction motor drive system with inverter output filter. This approach make use of a load torque state observer, which complete structure is presented along with the used control structure. Moreover, the demonstrated drive system operates without rotor speed measurement in conjunction with the multiscalar control. The verification of the demonstrated idea was performed on an experimental...
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Indirect Measurement of Motor Current Derivatives in PMSM Sensorless Drives
PublicationMotor current derivatives contain useful information for control algorithms, especially in sensorless electric drives. The measurement of motor current derivatives in electric motors supplied by voltage source inverter can be performed using di/dt transducers. However, in such a solution additional sensors have to be installed, e.g. Rogowski coils. Another approach is to measure current derivatives indirectly – by oversampling...
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Analytical modeling of electric drives for vehicle traction control systems
PublicationWheel-torque control bandwidth in vehicle dynamics model is crucial in evaluating optimal tracking ability of tire slip and in analysis of control system stability. Electric drives’ control dynamics are influenced by timing of digital control events, e.g. by sampling instant of motor currents. Reflecting this timing in drive analytical models is therefore important for analysis of vehicle traction systems. The paper considers five...
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Angle Tracking Observer for Filtering Rotor Position Estimates in Sensorless Electric Drives
PublicationSensorless electric drives use measurements of electrical quantities to estimate rotor position and speed. Measurement errors deteriorate the estimation accuracy, thus additional means are necessary to remove high-frequency components from estimated signals. This paper proposes to use an Angle Tracking Observer (ATO) for reducing noise in rotor position estimates, which is related to random errors in the measurements. A simplified,...
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Aggregated conducted interferences generated by group of asynchronous drives with deterministic and random modulation
PublicationThis paper addresses problems linked with electromagnetic interferences generated by group of three adjustable speed drives fed by frequency converters with deterministic and random modulation. Based on the experimental results it has been shown that decreasing of the conducted interferences in a case of random modulation is measuring phenomenon linked with selectivity of the EMI receiver.
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Synthesis of irregular motion mechanisms for production machine drives
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IPMSM Control for Electric Vehicle with Separate Wheel Drives.
PublicationPrzedstawiono propozycję hierarchicznej struktury rozproszonej sterowania pojazdu z niezależnym elektrycznym napędem kół. Zaproponowano algorytmy sterowania silnikiem synchronicznym z magnesami trwałymi. Przedstawiono strukturę stanowiska badawczego oraz wstępne wyniki badań symulacyjnych i laboratoryjnych układu.
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Experimental studies of circuit breaker drives and mechanisms diagnostics
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Space vector modulation in multilevel inverters of the servo drives of the trajectory measurements telescopes
PublicationUsing the MatLab/Simulink mathematical model of a three-phase three-level voltage inverter, the influence of the space-vector modulation (SVM) algorithm on the pulsations of the current (torque) of an AC motor in the range of low rotation speeds is considered. It is shown that the SVM of the second kind does not provide a pulsations level comparable to the pulsations of a sinusoidal pulse-width modulation (SPWM), both in the static...
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Frequency and time domain characteristics of digital control of electric vehicle in-wheel drives
PublicationIn-wheel electric drives are promising as actuators in active safety systems of electric and hybrid vehicles. This new function requires dedicated control algorithms, making it essential to deliver models that reflect better the wheel-torque control dynamics of electric drives. The timing of digital control events, whose importance is stressed in current research, still lacks an analytical description allowing for modeling its...
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The effect of the motor filters on earth fault current waveform in circuits with variable speed drives
PublicationIn circuits with variable speed drives distorted earth fault current flows. Earth fault current distortion influences the threshold of ventricular fibrillation. This paper presents earth fault current distortion in circuits with variable speed drives when motor filter is used. Two types of motor filter are analyzed. For every type of filter the effect of earth fault current distortion on ventricular fibrillation is evaluated.
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The effect of the motor filters on earth fault current waveform in circuits with variable speed drives
PublicationIn circuits with variable speed drives distorted earth fault current flows. Earth fault current distortion influences the threshold of ventricular fibrillation. This paper presents earth fault current distortion in circuits with variable speed drives when motor filter is used. Two types of motor filter are analyzed. For every type of filter the effect of earth fault current distortion on ventricular fibrillation is evaluated.
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Over-Voltage Studies in Inverter Fed Induction Motor Drives
PublicationW pracy przedstawiono metodę identyfikacji pojemności pasożytniczych uzwojeń silników asynchronicznych uwzględniającą ich rozłożony charakter. Przedstawiony szerokopasmowy model obwodowy uzwojeń silnika asynchronicznego pozwala na modelowanie zjawisk przepięciowych w silnikach asynchronicznych, w szczególności zasilanych poprzez przekształtniki energoelektroniczne. Zaproponowana metoda analizy umożliwia również określanie składowych...