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Wyniki wyszukiwania dla: ULTRASONIC MOTORS
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Properties of sensorless control systems based on multiscalar models of the induction motor
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Dual-task exercise as a therapy for executive motor function in Parkinson’s disease
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Dynamical processes in a multi-motor gear drive of heavy slabbing mill
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Speed sensorless asynchronous motor drive with inverter output lc filter
PublikacjaIn this paper a speed sensorless ac drive with inverter and output LC filter is proposed. A nonlinear, decoupled field oriented control algorithm with a flux and speed close-loop observer is used. In spite of using LC filter on the inverter output, the sensorless system works precisely. That result are obtained as a result of the appropriate estimation and control system use. The theory, simulation, and experimental results are...
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Use of Neural Networks in Diagnostics of Rolling-Element Bearing of the Induction Motor
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Automatic assessment of the motor state of the Parkinson's disease patient --a case study
PublikacjaThis paper presents a novel methodology in which the Unified Parkinson's Disease Rating Scale (UPDRS) data processed with a rule-based decision algorithm is used to predict the state of the Parkinson's Disease patients. The research was carried out to investigate whether the advancement of the Parkinson's Disease can be automatically assessed. For this purpose, past and current UPDRS data from 47 subjects were examined. The results...
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Induction motor control application in high-speed train electric drive
PublikacjaThe chapter presents an application of induction motor mechanical speed and load torque observers in high-speed train drives. The observers are applied for a 1.2-MW electric drive with an induction motor. The goal of using such observers is to utilize computed variables for diagnostic purposes of speed sensors and torque transmission system. The concept of diagnostic system is presented in this paper, and proper criteria are proposed....
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The basics of design and experimental tests of the commutation unit of a hydraulic satellite motor
Publikacjahe article presents an analytical method to design the commutation unit in a hydraulic satellite motor. It is shown that the size of the holes feeding the working chambers and their location on the plates closing those chambers depends on the geometrical dimensions of the working mechanism. The overlap in the commutation unit depends on the rotational speed range. It is demonstrated that the geometrical dimensions of the commutation...
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MCSA with Normalized Triple Covariance as a bearings diagnostic indicator in an induction motor
PublikacjaStatistics of bearing failures in induction motors indicate, that they constitute more than 40% of IM damage, therefore bearing diagnosis is very important. Vibration methods for bearing diagnostics have one major disadvantage - they require the availability of the machine for sensors installation. This is the reason for seeking new methods based on motor supply current analysis. Diagnosis of induction motors, conducted remotely...
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Use of Neural Networks in Diagnostics of Rolling-Element Bearing of the Induction Motor
PublikacjaBearing defect is statistically the most frequent cause of an induction motor fault. The research described in the paper utilized the phenomenon of the current change in the induction motor with bearing defect. Methods based on the analysis of the supplying current are particularly useful when it is impossible to install diagnostic devices directly on the motor. The presented method of rolling-element bearing diagnostics used indirect...
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Analysis of the possibilities of using of DME fuel in motor boat drive systems
PublikacjaThe characteristics of alternative fuel for diesel: dimethyl ether (DME) and an analysis of the potential to reduce emissions of toxic compounds by the engines when running on this fuel have been presented in this work. Basic types of design solutions of gas supply and control systems, possible for use in internal combustion engines with DME supply have been also presented. The paper presents a study of the legislation and an analysis...
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Gains selection of non-proportional observers of an induction motor with dyadic methods
PublikacjaThe paper presents issues related to calculation of gains of non-proportional observers of magnetic fluxes of an induction motor. A transformation is discussed, based on dyadic matrices, that affords possibility of applying well-known methods used in single-output systems to observers of multi-output systems. The impact of dyadic transformation on possibility of poles placement of the observer is analyzed....
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Induction Motor Bearings Diagnostic Using MCSA and Normalized Tripple Covariance
PublikacjaDiagnosis of induction motors, conducted remotely by measuring and analyzing the supply current is attractive with the lack of access to the engine. So far there is no solution, based on analysis of current, the credibility of which allow use in industry. Statistics of IM bearing failures of induction motors indicate, that they constitute more than 40% of IM damage, therefore bearing diagnosis is so important. The article provides...
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Sensorless induction motor drive with voltage inverter and sine-wave filter
PublikacjaThis paper presents a speed sensorless control system of an induction motor with an output LC filter. It is known that the parameters design of the filter gives sine wave motor supply voltage but complicates control and estimation process. The reason is that the voltage drop and phase shift between filter input and output signals are imposed, and hence the motor voltages and currents differ from the inverter output waveforms. To...
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Four-state stochastic model of changes in the reliability states of a motor vehicle
PublikacjaThe properties of semi-Markov processes have been generally characterized and the applicability of the theory of such processes to the determining of the reliability of motor cars and other road vehicles has been explained. A formal description of the process of changes in the motor vehicle technical states considered as reliability states and a model of this process in the form of a one-dimensional stochastic process have been...
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Broadband Modeling of Motor Cable Impact on Common Mode Currents in VFD
PublikacjaExamination of conducted EMI generation and propagation in AC motor drives fed by frequency converter requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. AC motor winding voltage transients and related common mode currents are significantly correlated with resonance effects occurring in converter's load circuits. Intensity levels of these phenomena depend...
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Influence of the Delay in Monitor System on the Motor Coordination of Musicians while Performing
PublikacjaThis paper provides a description and results of measurements of the maximum acceptable value of delay tolerated by a musician, while playing an instrument, that does not cause de-synchronization and discomfort. First, methodology of measurements comprising audio recording and a fast camera is described. Then, themeasurement procedure for acquiring the maximum value of delay conditioning...
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Control of the induction motor in the field weakening region based on the multiscalar model.
PublikacjaNajwiększą korzyścią płynąca z zastosowania w układzie regulacji modelu multiskalarnego jest pełne odsprzężenie toru sterowania prędkością i toru sterowania strumieniem. Wykorzystanie zależności występujących w modelu multiskalarnym pozwala na określenie maksymalnego momentu wyjściowego w układzie napędowym dla zakresu osłabiania pola. Zaproponowany został bezczujnikowy układ regulacji w oparciu o obserwator prędkości.
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Experimental Research Concerning Hydrodynamic Clutches Controlled by Increasing Distance Between Rotors
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Badania kompensacji luzów osiowych w hydraulicznych silnikach satelitowych = Researcg of axial clearances compensation in hydraulic satellite motors
PublikacjaW pracy doktorskiej przedstawiono koncepcje silnika z mechanizmem satelitowym III typu. Istotną nowością w koncepcji tego typu silnika satelitowego jest zastosowanie nowego specjalnego rozwiązania kompensacji luzów osiowych dla zmniejszania przecieków przez szczeliny czołowe mechanizmu. Ma to zapewnić ich eksploatację również z cieczami roboczymi o bardzo małych lepkościach i możliwość uzyskania małych prętkości obrotowych.
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Particle Swarm Optimization Based Optimal Design of Six-Phase Induction Motor for Electric Propulsion of Submarines
PublikacjaAbstract: Recent research reveals that multi-phase motors in electric propulsion systems are highly recommended due to their improved reliability and efficiency over traditional three phase motors. This research presented a comparison of optimal model design of a six phase squirrel cage induction motor (IM) for electric propulsion by using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). A six phase squirrel cage induction...
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Particle Swarm Optimization Based Optimal Design of Six-Phase Induction Motor for Electric Propulsion of Submarines
PublikacjaRecent research reveals that multi-phase motors in electric propulsion systems are highly recommended due to their improved reliability and efficiency over traditional three phase motors. This research presented a comparison of optimal model design of a six phase squirrel cage induction motor (IM) for electric propulsion by using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). A six phase squirrel cage induction...
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Induction motor bearings diagnostic indicators based on MCSA and normalized triple covariance
PublikacjaInduction motors are one of the most widely used electrical machines. Statistics of bearing failures of induction motors indicate, that they constitute more than 40% of induction motor damage. Therefore, bearing diagnosis is so important for trouble-free work of induction motors. The most common methods of bearing diagnosis are based on vibration signal analysis. The main disadvantage of those methods is the need for physical access...
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Modeling the impact of discretizing rotor angular position on computation of field-oriented current components in high speed electric drives
PublikacjaModern drives consist of alternating current electric motors, and the field-oriented control (FOC) of such motors enables fast, precise, and robust regulation of a drive's mechanical variables such as torque, speed, and position. The control algorithm, implemented in a microprocessor, requires feedback from motor currents, and the quality of this feedback is essential to a drive's control properties. Motor phase currents are sampled...
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New generation of the satellite hydraulic pumps
PublikacjaHydraulic satellite machines are known and produced in many versions, recognizable by the number of humps on their inner rotor and external gear, and therefore by the number of cooperating gears (satellites). All known shapes were however designed on the base of preliminary assumption that rotor’s and external gear’s pitch lines are formed by merging arcs, tangent to each other in the. This assumption makes calculations easier,...
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Some problems of self-excited vibrations of turbine rotors. Part I: The theoretical method
PublikacjaPrzedstawiono teoretyczną metodę określania uszczelnienia nadbandażowego lub dławicy zupełnej, które odgrywa największą rolę w generowaniu samowzbudnych drgań typu aerodynamicznego wirników turbinowych. Drgania harmoniczne układu wirnika turbiny opisane są macierzowym równaniem, a wymuszenia aerodynamiczne określane metodą współczynników wpływu.
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Five-phase Induction Motor Drive Operation During Stator Phase Fault
PublikacjaThe article presents the most important advantages of multi-phase electric drives. The construction of a five-phase squirrel cage induction motor together with possible stator winding distribution cases is presented, which affect the properties of such motor. Increased reliability of five-phase drives was indicated. The drive operation properties were confirmed by experimental results.
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Sensorless Disturbance Detection for Five Phase Induction Motor with Third Harmonic Injection
PublikacjaThe paper presents a sensorless disturbance detection procedure that was done on a five phase induction motor with third harmonic injection. A test bench was developed where a three phase machine serves as disturbance generator of different frequencies. The control of the machines is based on multi scalar variables that ensures an independent control of the motor EMF and the rotor flux. For disturbance identification a speed observer...
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Induction Motor Multiscalar Model Based Sensorless Control Using Power Measurement
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Research on a control system based on stepping motor for ship's controllable pitch propellers
PublikacjaW artykule przedstawiono opis stanowiska laboratoryjnego do badania serwomechanizmów okrętowych śrub nastawnych małej mocy oraz opracowany układ sterowania zdalnego śruby z wykorzystaniem elektrycznego silnika krokowego. Przedstawiono także wyniki pierwszej serii badań układu sterowania śruby nieobciążonej dla skokowego zadawanych wartości skoku śruby przy dwóch różnych prędkościach obrotowych silnika krokowego.
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Nonlinear control of induction motor in field weakning region with consideration of stator flux
PublikacjaMetody nieliniowgo sterowania mogą poprawić właściwości silnika indukcyjnego w stanach przejściowych wektora strumienia. Badano sterowanie oparte na modelu multiskalarnym silnika indukcyjnego w zakresie osłabiania pola. Dwie nowe zmienne wejściowe pojawiające się w modelu multiskalarnym są równe czynnej i biernej mocy silnika. Pokazano, że te wielkości mogą byc kompensowane, jeżeli rozważane są jako mierzone zakłócenia. Maksymalny...
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Increasing Electric Vehicles Reliability by Non-Invasive Diagnosis of Motor Winding Faults
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3D Hand Shape Modeling for Automatic Assessing Motor Performance in Parkinson's Disease
PublikacjaIn this paper a method for hand pattern processing to create a 3D hand model is presented. By applying a complete hand armature to the model obtained, an interpolation of three motor tests for an individual Parkinson's disease patient can be performed. To obtain the 3D hand model the top view of the hand from a web cam is analyzed. The hand contour is examined to find characteristic points that allows for dividing hand image into...
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Influence of geometrical and operational parameters on tooth wear in the working mechanism of a satellite motor
PublikacjaThis article describes the phenomena affecting the wear of the rotor of the working mechanism in a hydraulic satellite motor. The basic geometrical relationships that allow the calculation of the coordinates of the points of contact between the satellite and the rotor and the curvature are presented. A method for calculating the number of contacts of the satellite teeth with the rotor teeth and of the satellite teeth with the curvature...
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Supply current signal and artificial neural networks in the induction motor bearings diagnostics
PublikacjaThis paper contains research results of the diagnostics of induction motor bearings based on measurement of the supply current with usage of artificial neural networks. Bearing failure amount is greater than 40% of all engine failures, which makes their damage-free operation crucial. Tests were performed on motors with intentionally made bearings defects. Chapter 2 introduces the concept of artificial neural networks. It presents...
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Current based Normalized Triple Covariance as a bearings diagnostic feature in induction motor
PublikacjaDiagnosis of induction motors, conducted remotely by measuring and analyzing the supply current is attractive with the lack of access to the engine. So far there is no solution, based on analysis of current, the credibility of which allow use in industry. Statistics of IM bearing failures of induction motors indicate, that they constitute more than 40% of IM damage, therefore bearing diagnosis is so important. The article provides...
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Influence of water and mineral oil on the leaks in satellite motor commutation unit clearances
PublikacjaThe article describes the flow rates of mineral oil and water flowing, as working media, through the commutation unit of a hydraulic satellite motor. It is demonstrated that geometrical dimensions of commutation unit clearances change as a function of the machine shaft rotation angle. Methods for measuring the rate of this flow and the pressure in the working chamber are presented. The results of pressure measurements in the working...
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Selected dynamic properties of adaptive proportional observer of induction motor state variables
PublikacjaThis paper presents problems related to the design and the stability of adaptive proportional observer which is used for estimation of magnetic flux and motor speed in sensorless control systems of induction motor. The gain matrix of the observer was chosen by genetic algorithm and alternatively by pole placement method. It has been shown that adaptive proportional observer is stable if the...
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Properties of water in the region between a tubulin dimer and a single motor head of kinesin
PublikacjaA kinesin is a molecular motor that can perform movement on a microtubule track in a stepping-like manner. This motion is connected with processes of association and dissociation of kinesin and tubulin. Water is an important participant in these kinds of molecular interactions. This is why we have decided to investigate the dynamical and structural properties of water in the region between the kinesin catalytic domain and the tubulin...
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Stability of a proportional observer with additional integrators on the example of the flux observer of induction motor
PublikacjaArtykuł opisuje zagadnienia związane ze stabilnością proporcjonalnego obserwatora Luenbergera z dodatkowymi integratorami
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Resonant DC link inverters for AC motor drive systems – critical evaluation
PublikacjaIn this survey paper, resonant and quasiresonant DC link inverters are reexamined for AC motor drive applications. Critical evaluation of representative topologies is based on simulation and waveform analysis to characterize current/voltage stress of components, control timing constraints and feasibility. A special concern over inverter common-mode voltage and voltage gradient du/dt limitation capacity is discussed for motor bearing...
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Multiscalar Control Based Airgap Flux Optimization of Induction Motor for Loss Minimization
PublikacjaBased on the induction motor model, considering the core loss resistance that accounts for magnetic characteristic saturation, a speed control approach is devised with an adaptive full-order (AFO) speed observer. The induction motor model analysis is done sincerely in a stationary reference frame. The control approach incorporates a flux reference generator designed to meet optimal operational circumstances and a nonlinear speed...
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Influence of operating pressure on the durability of a satellite hydraulic motor supplied by rapeseed oil
PublikacjaThis article describes the results of a durability test of a hydraulic satellite motor supplied by rapeseed oil. The tests were carried out on a test stand in a power recuperation system. The tests of the motor were carried out at a constant shaft speed for three fixed pressure drops in the motor. This made it possible to demonstrate the influence of the motor operating pressure on the durability of the satellite mechanism. The...
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The computer numerical control system with permanent magnet synchronous motor servo-drives.
PublikacjaPrzedstawiono układ serwonapędów wieloosiowej maszyny sterowanej numerycznie. W układzie wykorzystano silniki synchroniczne z magnesami trwałymi oraz procesory synałowe DSP. Omówiono algorytmy sterowania nadrzędnego oraz problemy sterownia silnika PMSM.
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Determination of equivalent circuit parameters of an induction motor using field calculation software
PublikacjaSimulation of the drive system comprising a power electronic converter and an induction motor requires that the equivalent circuit parameters of the motor are known. These parameters can be either measured or calculated. A method of calculation of self and mutual inductances that are parameters of a polyphase model of the motor is presented in the paper. All self-inductances and mutual inductances have been calculated using the...
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Model and simulation tests of a squirrel-cage induction motor with oscillation of air gap
PublikacjaPrzedstawiono model matematyczny silnika, który pozwala na wprowadzanie ekscentryczności wirnika. Zaprezentowano obliczone widma prądu z wprowadzoną oscylacją wirnika, co z pewnym przybliżeniem odpowiada uszkodzeniu łożyska. Rezultaty symulacji pozwalają na określenie zależności pomiędzy oscylacją szczeliny powietrznej i składowych w widmie prądu.
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Transcriptomic landscape of blood platelets in healthy donors
PublikacjaBACKGROUND Blood platelet RNA-sequencing is increasingly used among the scientific community. Aberrant platelet transcriptome is common in cancer or cardiovascular disease, but reference data on platelet RNA content in healthy individuals are scarce and merit complex investigation. METHODS We sought to explore the dynamics of platelet transcriptome. Datasets from 204 healthy donors were used for the analysis of splice variants,...
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Interval vertex-coloring of a graph with forbidden colors
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Interval Vertex-Coloring of a Graph With Forbidden Colors
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Interval edge coloring of a graph with forbidden colors
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