Search results for: dual three-phase drives
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Przekształtniki tranzystorowe działające w trybie prądu trójkątnego
PublicationPrzekształtniki oparte na węgliku krzemu mogą być analizowane jako źródła napięcia lub prądu niezależnie od topologii przy odpowiednich parametrach filtru wyjściowego. Szczególnie interesujące są falowniki napięcia działające w trybie prądu trójkątnego. W referacie przedstawiono sterowanie trójfazowym falownikiem napięcia posiadającym właściwości źródła prądu. Pokazano, jak dobrać parametry filtru wyjściowego falownika. Oceniono...
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Discrete element method simulations of fracture in concrete under uniaxial compression based on its real internal structure
PublicationThe paper describes experimental and numerical results of concrete fracture under quasi-static uniaxial compression. Experimental uniaxial compression tests were performed on concrete cubic specimens. Fracture in concrete was detected at the aggregate level by means of three non-destructive methods: three-dimensional X-ray microcomputed tomography, two-dimensional scanning electron microscope and manual two-dimensional digital...
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Incorporating Iris, Fingerprint and Face Biometric for Fraud Prevention in e-Passports Using Fuzzy Vault
PublicationA unified frame work which provides a higher security level to e-passports is proposed. This framework integrates face, iris and fingerprint images. It involves three layers of security: the first layer maps a biometric image to another biometric image which is called biostego image. Three mapping schemes are proposed: the first scheme maps single biometric image to single biostego image, the second scheme maps dual biometric images...
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Voltage fluctuations on the main switchgear of the industrial power system supplying the rolling mill motors_part_2
Open Research DataThe dataset presents the voltage waveforms on the bus bars of the main switchgear of the industrial power network for the supply of rolling mills. The data was recorded during an experiment whose purpose was to determine a level of short-term and long-term flicker caused by voltage fluctuations. In the virtual application of flickermeter, a hardware...
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Influence of Antimony Substitution on Spontaneous Strain and Thermodynamic Stability of Lanthanum Orthoniobate
PublicationThe analysis of the antimony substitution influence on temperature dependence of unit cell distortion has been done. The values of spontaneous strain and Landau order parameter for three different antimony contents varied had been calculated. The phase transition occurring for antimony substituted lanthanum orthoniobate was found to be second order. The high temperature solution calorimetry method has been used to investigate...
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Sensorless IPMSM drive with rotor position estimator based on analysis of phase current derivatives
PublicationThis paper describes a sensorless Interior Permanent Magnet Synchronous Motor (IPMSM) drive designed for traction applications. Wide-speed sensorless operation is provided with the use of three methods of rotor position estimation designed for: a standstill, low- and high-speed range. The paper focuses on the high-speed estimation algorithm. The estimator uses the derivatives of motor phase currentsresulting from PWM modulation...
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Nonlinear control of five phase induction motor with synchronized third harmonic flux injection
PublicationThe paper deals with the novel control system for five phase induction motor (IM) that enables the injection of the rotor flux 3rd harmonic component. Two multiscalar models are transformed from the 1-1 and 2-2 vector models developed in the 1st and 3rd harmonic planes. Based on the obtained multiscalar models the synthesis of dual multiscalar control is established. The obtained two multiscalar control systems can independently...
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Hybridized SVPWM Algorithm for Multilevel CHB Inverter With DC-Link Voltage Control Capability
PublicationThe deployment of a space vector pulsewidth modulation (SVPWM) scheme in controlling cascaded H-bridge multilevel inverter (CHB MLI) is quite challenging; especially, when a substantial number of output voltage levels are involved and the dc-link voltages are out of balance. In this article, a simple SVPWM algorithm for CHB MLI is proposed. In the proposed algorithm, all the H-bridges in an inverter phase are treated as a single...
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Modern approach for determination of lactulose, mannitol and sucrose in human urine using HPLC-MS/MS for the studies of intestinal and upper digestive tract permeability
PublicationA new analytical procedure was described for the simultaneous determination of lactulose, mannitol and sucrose in urine, in which HILIC chromatography and tandem mass spectrometry detection are used. Sugars are orally administered for the estimation of intestinal permeability in children digestive tract. Samples were purified by dispersive solid phase extraction (d-SPE) using Amberlite MB150 resin. Raffinose was selected as an...
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Separation of Volatile Oxygen-containing Organic Compounds by Gas Chromatography - selectivity comparison of different polarity stationary phases
PublicationThis paper present a results of the separation of 36 reference compounds belonging to the group of Volatile Oxygen-Containing Organic Compounds (OVOCs) using capillary gas chromatography with flame ionization detector (GC-FID) and three stationary phases of different polarity. A selectivity has been studied regarding to OVOCs and n -alkanes. The most useful for the separation of the group OVOCs is a polar ionic liquid stationary...
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Modification of gradient HPLC method for determination of small molecules' affinity to human serum albumin under column safety conditions: Robustness and chemometrics study
PublicationIn the early stages of drug discovery, beyond the biological activity screening, determining the physicochemical properties that affect the distribution of molecules in the human body is an essential step. Plasma protein binding (PPB) is one of the most important investigated endpoints. Nevertheless, the methodology for measuring %PPB is significantly less popular and standardized than other physicochemical properties, like lipophilicity....
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Superconductivity in the Nb-Ru-Ge σ phase
PublicationWe show that the previously unreported ternary σ-phase material Nb20.4Ru5.7Ge3.9 (Nb0.68Ru0.19Ge0.13) is a superconductor with a critical temperature of 2.2 K. Temperature-dependent magnetic susceptibility, resistance, and specific-heat measurements were used to characterize the superconducting transition. The Sommerfeld constant γ for Nb20.4Ru5.7Ge3.9 is 91 mJ mol f.u. −1K−2 (∼3 mJ mol atom−1 K−2) and the specific-heat anomaly at...
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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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Effects of liquid phase modification on the values of surface tension of trickling liquid
Open Research DataDataset presents the values of surface tension of trickling liquid sampled from three running biotrickling filters.
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Four Level Diode-Clamped Back-To-Back Converter with Active DC Link Voltage Control
PublicationThis article presents the design and control of 4L-DC back-to-back converter. To solve the DC link voltage balancing problem in four-level converter a new three-level double chopper topology based on PO-PWM modulation was designed and successfully tested. Also, the paper describes two phase space vector pulse width modulation 2P-SVPWM based on the shape function of finite elements. The control structure with modified Dead-Beat...
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Broad Stopband, Low-Loss, and Ultra-Compact Dual-Mode Bandpass Filter Based on HMSIRC
PublicationIn this investigation, an ultra-compact dual-mode bandpass filter (BPF) with a wide stopband re-sponse is realized by using a half-mode substrate-integrated rectangular cavity (HMSIRC). The HMSIRC resonator is designed with a cavity that is rectangular in shape and has metallic vias along three of the sides. The fourth side is open-ended and contains microstrip feed lines. For the purpose of constructing a magnetic wall, a rectangular...
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Antimicrobial Activity of Chimera Peptides Composed of Human Neutrophil Peptide 1 (HNP-1) Truncated Analogues and Bovine Lactoferrampin
PublicationThree chimera peptides composed of bovine lactoferrampin and the analogue of truncated human neutrophil peptide 1 were synthesized by the solid-phase method. In two compounds peptide chains were connected via isopeptide bond, whereas in the third one disulfide bridge served as a linker. All three chimeras displayed significantly higher antimicrobial activity than the constituent peptides as well as their equimolar mixtures. The...
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Multicriteria decision analysis in ranking of analytical procedures for aldrin determination in water
PublicationThe study presents the possibility of multi-criteria decision analysis (MCDA) application when choosing analytical procedures with low environmental impact. A type of MCDA, Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE), was chosen as versatile tool that meets all the analytical chemists – decision makers requirements. Twenty five analytical procedures for aldrin determination in water samples (as...
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Effect of Different Bromine Sources on the Dual Cation Mixed Halide Perovskite Solar Cells
PublicationRecent research has shown that perovskite solar cells with a mixed dual A-cation have much better structural stability without loss of efficiency than single cation devices. Mixed cation perovskites create a lot of questions about the salts being used for the formation of the best-quality layer. Here, we have investigated three sources of bromide in the perovskite absorption layer, using lead bromide (PbBr2), formamidinium bromide...
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Rapid redesign of multiband antennas with respect to operating conditions and material parameters of substrate
PublicationThis work addresses geometry parameter scaling of multi-band antennas for Internet of Things applications. The presented approach is comprehensive and permits re-design of the structure with respect to both the operating frequencies and material parameters of the dielectric substrate. A two-step procedure is developed with the initial design obtained from an inverse surrogate model constructed using a set of appropriately prepared...
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THREE-LEVEL F-TYPE INVERTER
PublicationGiven the recent available IGBT switch modules up to 6.5 kV, 1200 A rating, the prospect of the diode-free variant topology of the three-level neutral-point-clamped (3-level, T-type) inverter in certain medium voltage applications is bright; due to its small part count and low conduction losses compared to the diode-clamped NPC inverter. However, within this voltage range, the input dc voltage rating of 50% of the switches per...
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Straightening of ship hull structure made of 316L stainless steel - tensile test of water cooled materia
Open Research DataThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries,...
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Straightening of ship hull structure made of 316L stainless steel - tensile test of reference material materia (transverse direction)
Open Research DataThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries,...
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Straightening of ship hull structure made of 316L stainless steel - tensile test of reference material materia (longitudinal direction)
Open Research DataThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries,...
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Straightening of ship hull structure made of 316L stainless steel - microstructure of naturally colled material
Open Research DataThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries,...
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Straightening of ship hull structure made of 316L stainless steel - microstructure of water cooled material
Open Research DataThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries,...
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Straightening of ship hull structure made of 316L stainless steel - microstructure of reference material
Open Research DataThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries,...
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Straightening of ship hull structure made of 316L stainless steel - tensile test of naturally cooled material
Open Research DataThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries,...
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Electrophoretic co-deposition of Mn1.5Co1.5O4, Fe2O3 and CuO: Unravelling the effect of simultaneous addition of Cu and Fe on the microstructural, thermo-mechanical and corrosion properties of in-situ modified spinel coatings for solid oxide cell interconnects
PublicationA systematic microstructural, thermo-mechanical and electrical characterization of simultaneous Fe–Cu doped Mn–Co spinel coatings processed by electrophoretic co-deposition on Crofer 22 APU is here reported and discussed. An innovative approach for the simultaneous electrophoretic deposition of three spinel precursors is designed, conceived and optimised, with the aim of outlining time- and energy-saving spinel modification routes....
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Sensorless Predictive Multiscalar-Based Control of the Five-Phase IPMSM
PublicationThis article proposes multi-scalar variables based predictive control of sensorless multiphase interior permanent magnet synchronous machine. Estimated parameters from adaptive observers are used to implement the proposed control scheme. The control approach is divided into two parts: for the fundamental plane, torque and its dual quantity from the multi-scalar model are directly predicted by the controller, and torque density...
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RANS-based design optimization of dual-rotor wind turbines
PublicationPurpose An improvement in the energy efficiency of wind turbines can be achieved using dual rotors. Because of complex flow physics, the design of dual-rotor wind turbines (DRWTs) requires repetitive evaluations of computationally expensive partial differential equation (PDE) simulation models. Approaches for solving design optimization of DRWTs constrained by PDE simulations are investigated. The purpose of this study is to determine...
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Project Team Management Supported by an Agent-Based Model
PublicationThis work is a continuation of a series of works about research into the use of multi-agent systems to support IT project management. Previous studies have shown the possibility of using a multi-agent in order to optimize management decisions concerning the selection of methods for project implementation. It was noted that the project manager's decisions are influenced by three fundamental parameters: the entropy of the project,...
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New Tetragonal ReGa5(M) (M = Sn, Pb, Bi) Single Crystals Grown from Delicate Electrons Changing
PublicationSingle crystals of the new Ga-rich phases ReGa~5(Sn), ReGa~5(Pb) and ReGa~5(Bi) were successfully obtained from the flux method. The new tetragonal phases crystallize in the space group P4/mnc (No. 128) with vertex-sharing capped Re2@Ga14 oblong chains. Vacancies were discovered on the Ga4 and Ga5 sites, which can be understood as the direct inclusion of elemental Sn, Pb and Bi into the structure. Heat capacity measurements were...
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Interaction of cisplatin and two potential antitumoral platinum(ii) complexes with a model lipid membrane: a combined NMR and MD study
PublicationIn this study, the interaction of cisplatin (1) and two potential antitumoral Pt(II) complexes (2 and 3) with a model DMPC bilayer was investigated by multinuclear NMR spectroscopy and MD simulations in order to understand its implication for the different antitumoral properties shown by the three complexes. In particular, 31P, 13C and 2H solid state NMR experiments were performed to obtain information on the phase structure, phase...
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Sensorless Control of Polyphase Induction Machines
PublicationThe basics of transformations of polyphase systems into orthogonal systems are explained. Vector models of induction machines in orthogonal planes are analysed and multiscalar models for rotor flux and main flux together with stator current are presented. A speed observer based on an extended model of the induction machine for selected variables is applied in the control system for the induction machine. On the basis of the model...
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Pressure-induced phase transitions in LnTe (Ln=La, Gd, Ho, Yb) and AmTe
PublicationThe structural behaviour under compression of different lanthanide (La, Gd, Ho, Yb) and actinide (Am) monochalcogenides is studied by means of in situ high-pressure x-ray diffraction. All the investigated compounds crystallize at ambient conditions within a cubic (B1) NaCl-type structure but show different behaviours at high pressures. LaTe and AmTe undergo B1 to B2 (CsCl-type structure) phase transitions, starting at 9 GPa and...
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Synthesis and structure of Bi 5 FeTi 3 O 15 ceramics
PublicationAim of the present research was to fabricate and study crystal structure and phase composition of Bi5FeTi3O15 (BTFO) ceramics exhibiting Aurivillius - type structure. By means of simultaneous thermal analysis and X-ray diffraction analysis the process of synthesis of BTFO ceramics has been studied. Mixed oxide method followed by pressureless sintering was used for ceramics preparation. Three endothermic thermal effects have been...
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Mechanical Behavior of Bi-Layer and Dispersion Coatings Composed of Several Nanostructures on Ti Substrate
PublicationThree coatings suitable for biomedical applications, including the dispersion coating composed of multi-wall carbon nanotubes (MWCNTs), MWCNTs/TiO2 bi-layer coating, and MWCNTs-Cu dispersion coating, were fabricated by electrophoretic deposition (EPD) on Ti Grade II substrate. Optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and nanoindentation were applied to study topography, chemical, and...
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Elliptical slot UWB monopole antenna
PublicationThe UWB monopole antenna with elliptical radiating slot end and microstrip feeding line terminated with radial stub have been designed, fabricated and measured. The antenna show return loss less than -12 dB in the whole UWB bandwidth. Linearity of the reflection coefficient phase product have also been achieved. Radiation patterns of the antenna measured at three selected frequency points indicated regular, approximately omni directional...
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Development of the sound field 3D intensity probe based on miniature microphones
PublicationThe engineered measuring probe uses three pairs of miniature microphones coupled. The signals from the microphones after an initial amplification are fed to differential circuits. Due to the required symmetry of the circuit it was necessary to select electronic components very carefully. Moreover, additional digital signal processing techniques were applied to avoid amplitude and phase mismatch. The view of the engineered probe...
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Effect of alkyl sulfate on the phase behavior of microemulsions stabilized with monoacylglycerols
PublicationIn this study the effect of an anionic surfactant (sodium dodecyl sulfate SDS) and oils (hydrocarbons: C12-C16) on the formation and phase behavior of the systems of oil/monoacylglycerols (MAG):SDS/propylene glycol/water has been investigated. The effects of the surfactant mixture on the phase behavior and the concentrationof water or oil in the systems were studied at three temperatures (50, 55, 60 C). Electrical conductivity...
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Testing Stability of Digital Filters Using Optimization Methods with Phase Analysis
PublicationIn this paper, novel methods for the evaluation of digital-filter stability are investigated. The methods are based on phase analysis of a complex function in the characteristic equation of a digital filter. It allows for evaluating stability when a characteristic equation is not based on a polynomial. The operation of these methods relies on sampling the unit circle on the complex plane and extracting the phase quadrant of a function...
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Recommendations for Urban Freight Policy Development in Gdynia
PublicationThe purpose of this paper was to provide practical recommendations on how to develop Gdynia’s urban freight policy based on actual planning experience and characteristics of potential measures. Freight policy scheme was developed as a result of three interrelated factors: a) the general procedure of the urban freight planning, b) the city's current planning stage analysis and, c) characteristics of urban freight objectives and...
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Novel bio-based thermoplastic poly(ether-urethane)s. Correlations between the structure, processing and properties
PublicationThe main purpose of this work was to analyze the effect of the number of unreacted isocyanate groups and the [NCO]/[OH] molar ratio during the chain extension of a prepolymer during the polymerization process on the structure, processing and selected properties of thermoplastic poly(ether-urethane)s. Three series of novel thermoplastic polyurethanes were obtained via a prepolymer route. Three prepolymers were synthesized from diisocyanate...
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The use of a 4 PB strain sweep fatigue test to evaluate characteristics of carbon grid reinforced asphalt beams
PublicationThe article presents research results concerning pre-bituminized carbon grids for asphalt pavement reinforcement, which are used to prevent cracking and crack reflection thus increasing bearing capacity and durability of pavement. Research program involved testing of large sized double-layer samples, both reinforced and unreinforced. The advantage of using a carbon grid was especially visible after crack initiation. The energy...
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A robust 18-pulse diode rectifier with coupled reactors
PublicationThe article presents the principle of operation and selected results of simulation and laboratory tests of the 18-pulse rectifier system with coupled reactors and small series active power filter. The presented system makes it possible to reduce, especially in distribution supply networks, undesired higher current harmonics. The 18-pulse nature of operation of the rectifier is reached using a set of coupled three-phase network...
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Experimental test results of an automatic voltage regulator with independent phase voltage controllers
PublicationThe growing number of distributed renewable energy sources and dynamic constant-power loads (e.g. electric vehicle charging stations) pose new challenges for network operators. These changes result in alterations to network load profiles and load flows, leading to greater voltage volatility. One effective solution to these problems can be the use of automatic voltage regulators (AVRs), which stabilize and symmetrize voltage output,...
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Bezczujnikowe sterowanie trakcyjnym silnikiem IPMSM małej mocy
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. Control of the IPMSM electromagnetic torque requires a precise estimation of the rotor angular position throughout the wide speed range. This involves using a set of estimation methods switched with the dependence on the actual rotor...
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Ionospheric scintillations computation using real-time GPS observations
PublicationThe following paper presents the results of quasi-real-time determination of the values of phase scintillations indices at the period of ionospheric disturbances that occurred as a consequence of the Sun flares observed on March 7 and 9, 2012. Double-frequency observations with 1-second measurement interval from the EPN (EUREF Permanent Network) network sites located at high latitudes were used for the analysis. To determine the phase...
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Triangulation-based Constrained Surrogate Modeling of Antennas
PublicationDesign of contemporary antenna structures is heavily based on full-wave electromagnetic (EM) simulation tools. They provide accuracy but are CPU-intensive. Reduction of EM-driven design procedure cost can be achieved by using fast replacement models (surrogates). Unfortunately, standard modeling techniques are unable to ensure sufficient predictive power for real-world antenna structures (multiple parameters, wide parameter ranges,...