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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

On-line proctection of electrical machines by microcomputer analysis of axial leakage flux

Dey, M. N. January 1983 (has links)
No description available.
2

Multi-speed electric hub drive wheel design

Woodard, Timothy Paul 19 November 2013 (has links)
Advances in electro-mechanical actuation have encouraged revolutions in automobile design which promise to increase fuel efficiency, reduce costs, improve safety and performance, and allow a wider range of architectural choices for the vehicle designer and manufacturer. This is facilitated by the concept of an intelligent corner (IC). The IC consists of traction, steering, camber, and suspension actuators working together to control the forces generated at the wheel/surface interface, allowing complete control of vehicle motion with completely active, as opposed to passive, systems. The most critical actuator to the longitudinal performance of an IC vehicle is the traction system, envisioned in this case as a hub mounted electro-mechanical actuator connected directly to the wheel. This traction actuator consists of a number of primary and supplementary components, including a prime mover, gear train, clutch, brake, bearings, seals, shafts, housing, etc. The consideration of these components in the design of an in-hub electric drive actuator is the subject of this report. Currently, gear trains are used in automobiles to match the operating speed of an internal combustion engine (ICE) to the speed of the vehicle on the road. The same need is anticipated for the hub drive wheel, although with fewer reduction ratio choices due to the responsiveness of the electric motor. Specifying a gear train design includes selecting a gear train architecture, and designing the gears to handle the expected loads. A review of gear design and gear train architectures is presented. A number of electric machines are used in industrial, and now more commonly, vehicle applications; of these, the switched reluctance motor (SRM) represents an excellent candidate for a vehicle prime mover due to its ruggedness, broad torque speed curve, low cost, and simplicity. Integrating the motor and gear train into an electro-mechanical actuator with multiple speeds requires consideration of other ancillary components. Brief design guides are presented for clutches, brakes, bearings, seals, and the structure for the in-hub wheel drive. Given the analytical descriptions of the drive wheel components, methods for managing the numerous design parameters are developed and expanded. Actuator specifications are chosen based upon meeting various vehicle performance requirements such as maximum speed, gradeability, acceleration, and drawbar pull. A proposed parametric drive wheel design is presented to meet the requirements of a generic heavy vehicle. The design demonstrates the feasibility of actuator technology that can be used to increase the performance, maintainability, and refreshability of hybrid electric vehicles while allowing open architecture paradigms to lower costs and spur new levels of manufacturing and innovation. / text
3

Μελέτη και κατασκευή εργαστηριακής διάταξης για τη φόρτιση ενός ηλεκτροκινητήριου συστήματος

Μπουκουβάλας, Σίλβεστρος 05 February 2015 (has links)
Η παρούσα διπλωματική εργασία πραγματεύεται το σχεδιασμό και την κατασκευή διάταξης φόρτισης ενός ηλεκτροκινητήριου συστήματος. Η εργασία αυτή εκπονήθηκε στο Εργαστήριο Ηλεκτρομηχανικής Μετατροπής Ενέργειας του Τμήματος Ηλεκτρολόγων Μηχανικών και Τεχνολογίας Υπολογιστών της Πολυτεχνικής Σχολής του Πανεπιστημίου Πατρών. Στα πλαίσια του θεσμού της πρακτικής άσκησης του τμήματος, ένα τμήμα της εργασίας αυτής εκπονήθηκε στο τεχνικό γραφείο ΛΙΑΣΚΟΣ Ο.Ε. Σκοπός είναι η κατασκευή ενός μετατροπέα πλήρους γέφυρας, που θα ελέγχει κατάλληλα μια μηχανή ξένης διέγερσης, η οποία συνδέεται μέσω ενός συστήματος μετάδοσης μ’ έναν κινητήρα με τελικό σκοπό την φόρτιση του κινητήρα με επιθυμητές ροπές για μελέτη της λειτουργικής συμπεριφοράς του. Αρχικά αναλύθηκε ένα ηλεκτροκινητήριο σύστημα και μελετήσαμε τα επιμέρους τμήματα που το αποτελούν. Παρουσιάζονται διάφορα είδη φορτίων με τις αντίστοιχες χαρακτηριστικές ροπής-στροφών καθώς και εφαρμογές που χρησιμοποιούνται. Επίσης αναλύθηκε συνοπτικά η μηχανή συνεχούς ρεύματος. Στη συνέχεια αναλύθηκε ο μετατροπέας πλήρους γέφυρας, οι τρόποι λειτουργίας του, με τους οποίους μπορεί να ελέγξει τη μηχανή συνεχούς ρεύματος ώστε να λειτουργεί στα τέσσερα τεταρτημόρια, ενώ ιδιαίτερη προσοχή δόθηκε στην ανάλυση των μεθόδων κατάλληλης παλμοδότησης των διακοπτικών στοιχείων. Στο επόμενο βήμα πραγματοποιήθηκε η προσομοίωση τόσο των επιμέρους συστημάτων όσο και του ολικού συστήματος, με σκοπό να εξακριβωθεί η ορθή λειτουργία του πριν την κατασκευή. Οι προσομοιώσεις πραγματοποιήθηκαν με την βοήθεια του λογισμικού Simulink του Matlab . Τέλος κατασκευάζεται η πειραματική διάταξη για να ληφθούν τα πειραματικά αποτελέσματα και να συγκριθούν με τα θεωρητικά, ώστε να εντοπιστούν και να δικαιολογηθούν τυχόν διαφορές μεταξύ της θεωρητικής ανάλυσης και των μετρήσεων στην πραγματική διάταξη, καθώς και για να εκτιμηθεί η απόδοση του συστήματος. / This thesis deals with the design and construction of a torque simulator device for an electrcic drive system. The thesis was conducted in the Laboratory of Electromechanical Energy Conversion, Department of Electrical and Computer Engineering of the University of Patras. The aim is to build a full-bridge converter, which will properly control a separately fed dc-machine, which is connected via a transmission system with a motor. The final goal is to load the engine with the desirable torque, in order to study it’s functional behavior. Initially we analyzed an electric drive system and studied the individual parts that make it up. We presented various kinds of loads with their corresponding torque-speed characteristic and applications in which they are used. We also analyzed, succinctly, the functional behavior of a DC machine. Then we analyzed the full-bridge inverter and it’s modes of operation, through which the DC machine can be controlled and operate in all four quadrants. Afterwards, methods for the proper pulse-control strategy of switching elements were studied. The next step was the simulation of both, subsystems as long as the overall system, in order to check the proper operation before construction. The simulations were performed using the software Simulink of Matlab. Finally the experimental setup was constructed, in order to obtain the experimental results and to compare them with the theoretical, to identify and justify any differences between the theoretical analysis and measurements on the real device, and to evaluate the system performance.
4

Design sportovního motocyklu na elektrický pohon / Design of sport electric motorcycle

Novotný, Jan January 2017 (has links)
The diploma thesis is focused on the design of a sport electric motorcycle, designed for road traffic for one-man crew. The aim of the concept is to distinguish it from the design of the current production, which is typically based on conventional motorcycles.
5

Design elektrického invalidního vozíku / Design of Electric Wheelchair

Schlosserová, Magdalena January 2016 (has links)
The goal of this diploma thesis is design of the electric wheelchair. The purpose is designed with knowledge of historic and todays devices for handicapped people. The design respects aesthetic, ergonomic and technical requirements. The electric wheelchair would go over the usual obstacles, would be solution of long sitting problems and also have an interesting and modern feel.
6

Lightweight friction brakes for a road vehicle with regenerative braking : design analysis and experimental investigation of the potential for mass reduction of friction brakes on a passenger car with regenerative braking

Sarip, S. Bin January 2011 (has links)
One of the benefits of electric vehicles (EVs) and hybrid vehicles (HVs) is their potential to recuperate braking energy. Regenerative braking (RB) will minimize duty levels on the brakes, giving advantages including extended brake rotor and friction material life and, more significantly, reduced brake mass and minimised brake pad wear. In this thesis, a mathematical analysis (MATLAB) has been used to analyse the accessibility of regenerative braking energy during a single-stop braking event. The results have indicated that a friction brake could be downsized while maintaining the same functional requirements of the vehicle braking in the standard brakes, including thermomechanical performance (heat transfer coefficient estimation, temperature distribution, cooling and stress deformation). This would allow lighter brakes to be designed and fitted with confidence in a normal passenger car alongside a hybrid electric drive. An approach has been established and a lightweight brake disc design analysed FEA and experimentally verified is presented in this research. Thermal performance was a key factor which was studied using the 3D model in FEA simulations. Ultimately, a design approach for lightweight brake discs suitable for use in any car-sized hybrid vehicle has been developed and tested. The results from experiments on a prototype lightweight brake disc were shown to illustrate the effects of RBS/friction combination in terms of weight reduction. The design requirement, including reducing the thickness, would affect the temperature distribution and increase stress at the critical area. Based on the relationship obtained between rotor weight, thickness and each performance requirement, criteria have been established for designing lightweight brake discs in a vehicle with regenerative braking.
7

Návrh části pohonu elektromobilu pro smíšený provoz / Design of part electric vehicle driving unit for mixed traffic

Matela, Petr January 2013 (has links)
Main goal of this master thesis is designing of a part of electric vehicle driving unit for mixed traffic. The drive purpose is to replace main drive of a utility van. First part of the thesis contains description of methodology used for energy consumption evaluation. In the next part there is description of current electric drive used in the van, design of a new one, best variant selection to suit company needs, energy consumption calculation, design and realization of the drive holder and final comparison of current and new drive design.
8

Proposta de integração de exoesqueleto com esteira ergométrica para auxílio em fisioterapia / Proposal of integration of exoskeleton with treadmill to assist on physiotherapy

Kuteken, Renato Suekichi, 1986- 25 August 2018 (has links)
Orientador: João Maurício Rosário / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-25T20:31:34Z (GMT). No. of bitstreams: 1 Kuteken_RenatoSuekichi_M.pdf: 4564566 bytes, checksum: 3e020109dd07850f4dc6d80cbf4e64b9 (MD5) Previous issue date: 2014 / Resumo: O treinamento de marcha suspensa sobre esteira ergométrica vem sendo aplicado com sucesso em pacientes que perderam os movimentos dos membros inferiores, proporcionando uma reabilitação eficaz, com fortalecimento muscular e redução de atrofias. Além do treino de marcha, exoesqueletos também vem sendo utilizados na recuperação funcional, monitorando e atuando sobre o corpo do paciente. Este trabalho propõe a integração entre um exoesqueleto e uma esteira ergométrica no treinamento de marcha com suspensão de peso através de um sinal de acionamento para a esteira que compense os movimentos das pernas e mantenha fixa a posição do centro de massa do corpo. Este sinal de referência é elaborado a partir de valores angulares obtidos do sensoriamento das juntas do exoesqueleto, aplicados ao modelo cinemático da perna. O desenvolvimento do projeto se deu em duas plataformas, com o uso do Arduino para a aquisição da implementação física e do MATLAB para o desenvolvimento em software / Abstract: The body weight supported gait training on treadmill has been successfully applied on patients who lost their lower limbs movements, providing an efficient rehabilitation, with muscle strengthening and reduction of the atrophy. Besides gait training, exoskeletons have also been used on functional rehabilitation, monitoring and actuating on the patient¿s body. This work proposes the integration between an exoskeleton and a treadmill on the weight supported gait training through a driving signal for the treadmill that compensates the movements of the legs and hold still the position of the center of mass of the body. This reference signal is elaborated making use of angular values obtained from joint sensors on the exoskeleton, applied to the kinematic model of the leg. The development of the project occurred in two platforms, with the use of Arduino to acquisition on the physical implementation and MATLAB to software development / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica
9

Design lehkého tandemového válce s elektrickým pohonem / Design of Light Tandem Roller

Paška, Tomáš January 2021 (has links)
The master thesis deals with the design of a light tandem roller with an electric drive. The final design of the machine is designed in regard to the knowledge from design and technical analysis and the shortcomings of current rollers. The purpose of this work is to design a tandem roller which will respect the ergonomic requirements of the operator.
10

Řízení manipulační linky suchých výrobků / Control of manufacturing line

Stříž, Martin January 2008 (has links)
The main task of this project was to design a program for control system of dry concrete product handling line. This manufacturing line is controlled by a programmable logical controller Simatic S7 300 produced by Siemens company. A graphical touch panel TP 177A and a control desk with buttons are used as human machine interface. The developed program contains functions for control conveyors, manipulator and cleaning station. Management of formulations stored in PLC by operator is also included in program. The theoretical part deals with dimensioning of drives for two mechanical systems of this manufacturing line. Choice of power output of the electric motors depends on required torque. A fundamental principles and rules of five basic programming languages for PLC in accordance with standard IEC 61131-3 are specified here. The practical part describes project creation in Step 7 software and functions and capabilities of projected system by means of user manual.

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