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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Development of small electrical machines utilising permanent magnets

Amrani, Mustapha January 1989 (has links)
No description available.
2

Design of rotor windings to improve the performance of converter-fed synchronous machines

Soltani-Zamani, J. January 1988 (has links)
No description available.
3

Parameter Estimation in a Permanent Magnet Synchronous Motor

Tenerz, Mikael January 2011 (has links)
This thesis adresses the problem of estimating the parameters in a permanent magnet synchronous motor (PMSM). There is an uncertainty about the parameters, due to age and tolerances in the manufacturing process. Parameters such as the resistance and the current to torque factor Kt, changes with respect to temperature as well. The temperature in the motor varies in normal motor operation, due to variations in angular velocity and torques. Online estimation methods with the model reference adaptive systems technique (MRAS) and offline methods are presented. The estimation algorithms are validated in simulations with Matlab/Simulink and also evaluated with experimental data. Experiments were performed on a range of different motors, in realistic scenarios. Relevant factors such as the angular velocity of the rotor and the impact of the gravity force are investigated. The results show that it is possible to estimate the motor factor $K_t$, with an accuracy of two percentage from its reference value in normal industry conditions. The estimated value of the motor inductance is within 25 percentage of the calculated reference value. The resistance however is affected by the resistance in the cables from the motor to the measurement device. With the cable resistance included in the calculations, the estimate still often exceeds double the value of the reference value.
4

Matematický model synchronního motoru s permanentními magnety / Mathematical model of synchronous motor width permanent magnet

Fajkus, Petr January 2011 (has links)
The work is focused on the design of synchronous motor control with field weakening possibility. At present synchronous motors used in many applications. Often is used synchronous motor with permanent magnets. This type of motor may have different transverse and axial inductance. In most cases it is desirable to design the engine using a computer model. Therefore the synchronous motor described mathematically in order to create the model of motor. At work is also crated model of synchronous motor control. The control is designed for the highest possible speed range. Therefore, the motor control is consist of two parts. Speed is controlled by voltage in the first part. In the second part speed is controlled by field weakening. Everything is created and simulated in a computer program MATLAB-SIMULINK.
5

Řízení synchronních pohonů / Conrol of synchronous drives

Mrtvý, Bohuslav January 2011 (has links)
The document describe servo drive by B&R and the control algorithms with vector control. There is also mathematic model of synchronous motor, design of control the system of two connected motor and implementation these algorithms in to the PLC and Acopos. The Master’s Thesis contains confrontation of results of real system and ideal model.
6

Parameter Measurement of 0.33 HP Synchronous Machine Using ITECH Digital Power Supply

Kargol, Andrew 01 June 2023 (has links) (PDF)
The classical methodologies for synchronous machine modeling provide a solid estimation for synchronous machine behavior but are limited in terms of accuracy due to the assumptions made in the modeling process. The equivalent circuit model developed by the classical approach breaks down the entire machine into a singular impedance component. This allows the model to be generated more quickly but limits its accuracy. In the pursuit of developing a more realistic model, this thesis outlines the parameter measurement of a Hampden SM-100 synchronous machine. In determining the SM-100’s experimental parameters, this thesis executes and analyzes new experimental approaches to synchronous machine modeling. With the results of these approaches, a model for the Hampden SM-100 synchronous machine is developed that considers the rotor, stator, and core parameters of the synchronous machine separately.
7

Simulační modely synchronního stroje pro výukové potřeby / PMSM models for educational purposes

Lidmila, Petr January 2016 (has links)
This master´s thesis deals with synchronous motor model creation in MATLAB – Simulink program, with purpose of usage in AC Drives class. Models are created for motor with permanent magnets and for motor with wound rotor. The models are designed to enable simulation with both different longitudinal and transverse inductance, thus with salient rotor and non-salient rotor. The models can also be powered directly from three-phase sinusoidal source or a simple vector control can be used for their acceleration. All models are aligned so that their parameters can be set in only one m-file. Furthermore, automatic generation of phasor diagrams for steady-state motor, which serves as an interactive tool in class, is also created.
8

The optimal application of common control techniques to permanent magnet synchronous motors

Treharne, William January 2011 (has links)
Permanent magnet synchronous motors are finding ever increasing use in hybrid and electric vehicles. This thesis develops a new control strategy for Permanent Magnet Synchronous Motors (PMSMs) to reduce the motor and inverter losses compared to conventional control techniques. The strategy utilises three common control modes for PMSMs; brushless DC with 120°E conduction, brushless DC with 180°E conduction, and brushless AC control. The torque and power output for each control mode is determined for an example motor system using a three phase axial flux YASA motor and an IGBT inverter. The loss components for the motor and inverter are also estimated using a combination of analytical and simulation techniques and results are then validated against experimental measurements. Efficiency maps for each control mode have been used to determine an optimal mode utilisation strategy, which minimises the total system losses and maximises the available motor torque output. The proposed control strategy switches between the three control modes without interruption of motor torque to maximise the system efficiency for the instantaneous operating speed and demanded torque output. The benefits of the new strategy are demonstrated using an example vehicle over a simulated drive cycle. This yields a 10% reduction in losses compared to conventional brushless AC control.
9

Sensorless control of permanent magnet synchronous motor / Commande sans capteur d'un moteur synchrone a aimants permanents

Shah, Dhruv 31 March 2011 (has links)
Nous proposons dans ces travaux, une solution aux problèmes de longue date posés par le control sans capteur d’une machine électrique. Cette solution consiste à élaborer un contrôleur asymptotiquement stable qui régule la vitesse du moteur en mesurant uniquement les coordonnées électriques. Nous l’avons appliqué à un moteur synchrone à aimant permanent non saillant, perturbé par un couple de charge constant non connu. Le schéma proposé est un observateur non linéaire d’ordre 4, basé sur le control qui ne dépend pas d’opérations non robustes intrinsèques au système, comme l’intégration de boucle ouverte à un système dynamique et ce schéma peut être facilement intégrée en temps réel. Le contrôleur est facile à commander par l’ajustement du gain qui détermine directement le taux de convergence de la position et de la vitesse et charge le couple d’observateurs. Les simulations et les résultats expérimentaux mettent en évidences les bonnes performances ainsi que la robustesse des paramètres d’incertitudes du schéma que nous proposons. La comparaison par simulation avec un contrôleur sans capteur à champ orienté présenté récemment dans la littérature, a également été effectuée. La thèse se termine par des remarques de conclusion et des propositions de sujet de recherche s’inscrivant dans la continuité de ces travaux. / A solution to the longstanding problem of sensorless control of an electrical machine is provided in this work. That is, the construction of an asymptotically stable controller that regulates the mechanical speed of the motor, measuring only the electrical coordinates. The result is presented for a non-salient permanent magnet synchronous motor perturbed by an unknown constant load torque. The proposed scheme is a fourth order nonlinear observer-based controller that does not rely on-intrinsically nonrobust-operations like open-loop integration of the systems dynamical model nor signal differentiation, and can be easily implemented in real time. The controller is easy to commission, with the tuning gains directly determining the convergence rates of the position, speed and load torque observers. Simulation and experimental results that illustrate the good performance, as well as the robustness to parameter uncertainty, of the scheme are presented. A simulated comparison with a sensorless field-oriented controller, recently proposed in the drives literature, is also carried out. The thesis is closed with some concluding remarks and some potential research topics generated from this work.
10

Étude et réalisation d'une nouvelle structure d'un moteur synchrone supraconducteur / Study and realization of a new structure superconducting synchronous motor

Alhasan, Rada 24 February 2015 (has links)
Dans ce travail, nous avons réalisé et validé le fonctionnement d’une nouvelle structure de moteur supraconducteur composé d’un inducteur supraconducteur et d’un induit en cuivre. La structure originale de ce moteur est basée sur le principe de modulation de flux par l’utilisation d’un écran supraconducteur massif. Après avoir modélisé la machine par éléments finis, la construction du moteur a été achevée avec succès, une étape très délicate présentant de nombreuses difficultés. Les résultats montrent, non seulement la faisabilité technique de la machine, mais également son bon fonctionnement. Les essais, à vide, en court-circuit et en charge nous ont permis de déterminer les éléments d’un modèle de Ben-Eschenburg de ce moteur. En conclusion l’objectif de ce projet a été atteint avec succès / In this work, we have achieved and validated a new superconductor motor structure, consisting of a superconducting inductor and of an armature of copper. The original structure of this motor is based on the principle of flux modulation by the use of a bulk superconductor screen. After modeling the machine by finite elements, the construction of the engine has been achieved successfully, a very delicate stage with many difficulties. The results show not only the technical feasibility of the machinery, but also its good operation. The experiments with and without load, and the one under short circuit, allowed to determine the elements of the Ben-Eschenburg model for this machine. As conclusion, the aim of the project was successfully achieved

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