• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 13
  • 8
  • 1
  • 1
  • 1
  • Tagged with
  • 26
  • 10
  • 9
  • 8
  • 8
  • 8
  • 7
  • 7
  • 7
  • 6
  • 6
  • 6
  • 6
  • 6
  • 5
  • 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

Traction machine winding and magnet design for electric vehicles

Niu, Xin January 2017 (has links)
Work had been established for traction machine design aspects in this research. The effect of multiphase design for Permanent Magnet (PM) machine was investigated. The electromagnetic characteristics of both 3-phase and 9-phase machine, along with different magnet designs, were simulated and analyzed by using the program developed during the process. The software used were FEMM and MATLAB. The iron loss for different designs was established, based on the analytical flux density obtained by 2-D stepping FEA method. The harmonic of flux waveform and rotating field were also considered for difference areas in the machine models. The prediction was compared with experimental data collected in open circuit. The simulation result shown that there was a minimum 4% torque gain and noticeable less torque ripples for 9-phase machine, comparing with 3-phase one, with the same excitation phase current. The embedded magnet rotor design was suggested to monitor the demagnetization of each magnet closely, since some area of the magnet could be demagnetized even when the working point of magnet was well distance away from the nonlinear region of its characteristic. There were about 6% less iron loss was produced in 9-phase model than 3-phase model. The implemented method for calculating iron loss was more accurate within 3500 rpm rotor speed comparing with other approaches.
2

Mikrogenerátor / Microgenerator

Pospíšil, Kamil January 2008 (has links)
In this master’s thesis gives an overview of the finite element method (FEM) as used in electrotechnical practice. It deals with calculations of electric and magnetic fields. The task can be solved using ANSYS, FemLab, Femm, Quickfield and next software. Femm is the one I have chosen. The programs are described here, and their use is demostrated on examples. The outcome of the project is a calculation of magnetic field of a microgenerator in a stationary and dynamic field.
3

Měření a analýza jednofázového transformátoru s pomocí LabVIEW / Measurement and analysis of single-phase transformer

Princ, Pavel January 2010 (has links)
The aim of that diploma thesis is low power transformer simulation via its substitutitional circuitry.As Instrument for matematical description of model and simulation of various operating situations with different amplitude and types of load was used Labview software. The software was simultaneously used for real transformer measurement and to compare these results with calculated values. The created program is also applied for measuring excercise for students. In The thesis is described measured transformer in terms of final elements method in FEMM software and there is showed the procedure of its design.
4

Design and Manufacturing of IPM Synchronous Motor for Field Weakening Operation

Finnman, Jonas, Eketorp, Erik January 2013 (has links)
Rotor designs for permanent magnet synchronous machines suitable for field weakening operation have been evaluated for use with an existing drive system. The designs have been simulated with the FEM-based software Finite Element Method Magnetics (FEMM). Based on the results two different internal magnet rotors have been constructed and tested. Both designs significantly improved the speed range while maintaining or improving magnet utilisation. The implementation of field weakening algorithms in drive electronics is complex and need thorough optimisation for stable operation. Internal permanent magnet rotors are a good alternative to surface mounted designs and enables a wider speed range through improved field weakening capabilities.
5

Transmission planétaire magnétique : étude, optimisation et réalisation / Magnetic planetary transmission : study, optimisation and realisation

Gouda, Eid Abdelbaki Ahmed 20 June 2011 (has links)
Le travail présenté dans ce mémoire porte sur l'étude, l'optimisation et la réalisation d'une transmission planétaire magnétique. Dans notre thèse nous essayons de répondre à quelques questions intéressantes sur la possibilité de remplacer un train planétaire mécanique par un train planétaire magnétique, est-ce que la formule de Willis reste valable pour le train planétaire magnétique et est-ce que les trains magnétiques ont des performances similaires à celles des trains mécaniques ? Donc nous étudions, le remplacement du train mécanique par une transmission magnétique. Nous montrons que le train magnétique a un volume moindre, des pertes inférieures et plusieurs autres avantages. Notre but dans cette thèse est d'obtenir un "design" optimal d'un train magnétique. Nous utilisons un logiciel de calcul par éléments finis pour l'étude électromagnétique et nous cherchons également à optimiser les dimensions de ce train. Pour cela nous utilisons la méthode d'optimisation par essaim de particules (OEP). Un prototype a été réalisé ce qui permet de confronter les résultats de simulation et expérimentaux. / The work presented in this thesis deals with the study, the optimisation and the realisation of a magnetic planetary transmission. We try to answer some questions about the possibility of replacing the mechanical planetary gear used in industrial machines by a magnetic planetary gear; is the formula of Willis still valid for the magnetic planetary gear and are the magnetic planetary gear performances at least similar to ones of the mechanical gears? We study the replacement of the mechanical planetary gear by a magnetic one. We show that the magnetic one has a smaller volume, lower losses and many other benefits. The objective of this work is to obtain an optimum design of a magnetic planetary gear. We use a finite element software to study the magnetic behaviour of the device and we also perform the optimization of the dimensions of the magnetic planetary gear. The particle swarm optimization method (PSO) has been used. A prototype has been built so the computation results has been compared to the experimental ones.
6

Magnetostrikční vibrační generátor / Magnetostriction vibration power generator

Šumpelová, Jana January 2017 (has links)
This thesis deals with the idea of energy harvesting from mechanical vibration. It describes the magnetostrictive principle as a possibility to obtain an electrical energy. It is about a generator made of a beam with Terfenol-D material and a coil. The model of this device is created in Matlab/Simulink and FEMM application. For various values of measured vibration, these methods are then compared. In FEMM, you can improve energy gain by modeling of various environmental conditions and with using of another materials (e.g. by adding of permanent magnets). The outcome of the this thesis expresses the ability to harvest the energy with designed magnetostrictive generator compared to the already created models of the piezoelectric and electromagnetic generator. Based on these results, it is possible to determine which generator is more suitable for particular application.
7

Vázané modelování asynchronního motoru metodou fyzikálního modelování a metody konečných prvků / Constrained Modeling of Induction Motor Using Physical Modeling and FEM

Trávníček, Tomáš January 2017 (has links)
Tato práce řeší návrh komplexního modelu asynchronního stroje, pomocí něhož se dá stroj analyzovat. Model se skládá z dílčích modelů, které popisují asynchronní stroj z hlediska elektro-magnetického, elektrického a tepelného. Elektromagnetický model je řešen pomocí metody koneč-ných prvků v programu zvaném FEMM. Další výpočty jsou provedeny pomocí Matlabu. Tepelný model počítá s ustáleným stavem stroje v požadovaném pracovním bodě. Elektrický model je řešen pomocí náhradního schématu, ze kterého jsou odvozeny vztahy pro elektrické veličiny. Výsledný propojený model je naprogramován v Matlabu a slouží jako nástroj pro analyzování asynchronního stroje.
8

Elektromagnetický rezonátor jako zdroj elektrické energie na železniční trati / Electromagnetic energy harvesting resonator for train trackside

Rusková, Miroslava January 2018 (has links)
The aim of the diploma thesis was to design an electromagnetic generator to the purpose of supplying signalling and safety devices on the rail tracks. The electromagnetic generator is a separate electrical source, which is mainly needed for safety in the case of not covered tracks by electrical installation. The thesis proposes two types of electromagnetic generator and one with non-linear stiffness, which are designed for the passage of trains with low frequency.
9

Výpočet parametrů asynchronního motoru metodou konečných prvků / Calculation of parameters of induction motor using FEM

Pešek, Michal January 2011 (has links)
This project is focused on finite element method, for purposes of asynchronous motor modeling. Program FEMM is used here, which works with two-dimensional models. The model is based on an existing motor. Then was conducted a series of simulations that are used to calculate the parameters of the circuit model. Then was measured the existing asynchronous motor and performed the calculation of the circuit model parameters of the motor. Compared with data obtained from motor and models Then was compared their torque characteristics. Moments was identified at certain slip frequencies and voltage or current in circuit model.
10

Modelování přechodných dějů u synchronních stroju pomocí MKP / FEA modelling of synchronous machine

Ficza, Tibor January 2010 (has links)
Táto práca sa zaoberá s modelovaním synchronného stroja s permanentnými magnetmi pomocou metody konečných prvkov. K modelovaniu sme si zvolili 3 fázový synchronný stroj s permanentnými magnetmi na povrchu rotora z firmy VUES. Najprv vypočítame parametre stroja a potom spravíme statický model pomocou programu FEMM a Matlab a budeme hladať možné riešenia na 2D dynamický model. Pomocou programu Ansys Workbench spravíme 3D model tohoto stroja budeme a porovnávať výsledky simulácie.

Page generated in 0.0273 seconds