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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.
11

Investigation of compact rotor position sensor technology

Stahrberg, Casper, Pallin, Oscar January 2021 (has links)
Electric vehicles are increasing on the market and new technologies are being investigated because of the demand placed on electrified drivelines to provide maximum efficiency. Electric motors are expected to provide high efficiency and thus precise and compact designs of sensors for electric motors are requested. Market sensors offers a broad variety of sensors which are useful and optimal for different applications. Inductive sensors are investigated by industries because of their characteristics of having high accuracy, robustness, compact and flexible design and tolerant to harsh environments. This thesis is an investigation of inductive position sensors for automotive rotor applications,requested by one of Sweden’s largest companies within the automotive industry. The goal of the project is to design and implement theory of tradtional resolver technology on a printed circuit board (PCB) and conduct concept verifications of the system. Furthermore a new concept in the design is introduced and applied to the angular position sensor, working as a vernier scale and improve the resolution. Results and outcomes of this thesis are meant to facilitate future work and breakthroughs regarding inductive position sensors. This thesis aim to conduct a deep dive in electronics and signal processing and to derive the fundamentals of electromagnetism, from Maxwell’s equations to modern sensor design and to bring a new discussion to the table regarding the traditional measuring target used for rotor position in automotive industries. A new design working as rotor target design is presented and verified in this thesis and the results and outcomes are meant to facilitate future work and breakthroughs regarding inductive position sensors and potentially increase the accuracy and thus the efficiency of electric vehicles.
12

Estimation and Compensation of Load-Dependent Position Error in a Hybrid Stepper Motor / Estimering och kompensering av lastberoende positionsfel i en elektrisk stegmotor

Ronquist, Anton, Winroth, Birger January 2016 (has links)
Hybrid stepper motors are a common type of electric motor used throughout industry thanks to its low-cost, high torque at low speed and open loop positioning capabilities. However, a closed loop control is often required for industrial applications with high precision requirements. The closed loop control can also be used to lower the power consumption of the motor and ensure that stalls are avoided. It is quite common to utilise a large and costly position encoder or resolver to feedback the position signal to the control logic. This thesis has explored the possibility of using a low-cost position sensor based on Hall elements. Additionally, a sensorless estimation algorithm, using only stator winding measurements, has been investigated both as a competitive alternative and as a possible complement to the position sensor. The thesis work summarises and discusses previous research attempts to adequately measure or estimate and control the hybrid stepper motors position and load angle without using a typical encoder or resolver. Qualitative results have been produced through simulations prior to implementation and experimental testing. The readings from the position sensor is subject to noise, owing to its resolution and construction. The position signal has been successfully filtered, improving its accuracy from 0.56° to 0.25°. The output from the sensorless estimation algorithm is subject to non-linear errors caused by errors in phase voltage measurements and processing of velocity changes. However, the dynamics are reliable at constant speeds and could be used for position control.
13

Capteurs de position innovants : application aux Systèmes de Transport Intelligents dans le cadre d'un observatoire de trajectoires de véhicules / New position sensors : application to Intelligent Transport Systems within the context of estimation of vehicule trajectories

Aubin, Sébastien 12 December 2009 (has links)
Améliorer la sécurité routière passe par une meilleure compréhension des causes d'accidents. Il est donc nécessaire de développer des observatoires discrets pour étudier la manière de conduire de tous les automobilistes. Une partie de cette analyse implique l'utilisation de capteurs mesurant les trajectoires des véhicules sur une portion de route. Deux capteurs innovants ont été crées pour pallier au manque de capteurs suffisamment précis pour ces travaux de recherche : le premier est un capteur à fibres optiques présentant une succession de réseaux de Bragg et le second, protégé par un brevet, est fondé sur une technologie résistive. Le premier repère la déformation locale de fibres optiques noyées à moins d'un centimètre sous la surface de la chaussée. Il utilise la variation de longueurs d'onde engendré par l'extension de la fibre à la zone de contact roue - sol. En utilisant un algorithme adéquat, il est insensible à la température. Le second est constitué de deux conducteurs dont un est résistif. Le poids du véhicule engendre un contact électrique entre les deux conducteurs, transformant la résistance électrique de l'ensemble. Les modèles développés, électrique ainsi que de variation thermique, permettent sa meilleure utilisation. Ils ont été soumis à une expérimentation sur une route départementale. Le capteur optique s'avère plus performant mais coûteux. Le deuxième n'est pas assez robuste mais présente des perspectives intéressantes. / This action stake is not technology for itself. It is a great help the development of new safety functions, e.g. the estimation of driver’s behaviour based uponthe vehicle’s trajectory. This trajectory is determined via two sensors we developed. This system must not disturb the driver and should therefore remain invisible to him. The first one is a fiber Bragg grating (FBG) sensor. It detects local strain due to the vehicle weight. The fiber is embedded in the road thanks to resin used in other traffic sensors. The vehicle location is spotted according to the variations of Bragg wavelengths. The fiber extension located under the ground - wheel contact zone changes the step of the Bragg grating. The second one is based upon two conductors. One of them has a grater electrical resistance. The vehicle’s weight creates a link between the two conductors. The resulting electrical resistance provides a lateral position estimation of the vehicle. Electrical and thermic models and simulation even increase the sensor reliability. A caveat is lodged. Both of them were tested on a secondary road. To put in a nutshell, the FBG sensor gives better results but is very expensive (sensors and interrogator too). The resistance sensor is not much raw nevertheless it has interesting perspectives.
14

Návrh vřeteníku soustruhu / Design of spindle for lathe

Sovadina, František January 2021 (has links)
The thesis deals with the design and construction of headstocks of a turning centre. The aim is to design a spindle with an output of 20 kW and a maximum speed of 5000 1/min. The research part of the thesis is focused on the description of the basic parameters of the headstock and turning centres needed for the construction of the headstock and contains an analysis of the available spindles on the market. The next part of the thesis deals with the selection and calculation of cutting conditions and the necessary parameters. Analytical calculations are then verified using FEM analysis. At the end of the thesis, a 3D model was developed and headstock drawing documentation.
15

Разработка учебно-лабораторного комплекса по мехатронике и робототехнике : магистерская диссертация / Development of the mechatronics and robotics education-laboratory unit

Клюхин, М. В., Klyukhin, M. V. January 2021 (has links)
Цель работы – спроектировать и реализовать аппаратную и программную часть учебно-лабораторного комплекса по мехатронике и робототехнике. Определены основные требования к объекту, требования проанализированы, и на их основе разработан комплекс на основе стенда по автоматизированному электроприводу и робота-манипулятора. / The aim of the work is design and implementation the hardware and software parts of the educational unit for mechatronics and robotics education. The basic requirements for the unit have been determined, the requirements have been analyzed, and on their basis a unit that consists of an automated electric drive and a robotic manipulator has been designed.
16

Continuité de service des entraînements électriques pour une machine à induction alimentée par le stator et le rotor en présence de défauts capteurs / Electrical drive service continuity for an induction machine fed by stator and rotor in presence of sensor faults

Abdellatif, Meriem 03 April 2010 (has links)
Le développement de commandes en boucle fermée pour des entraînements électriques nécessite l'installation de capteurs pour avoir l'information de la rétroaction. Cependant, un éventuel défaut survenant sur l'un des capteurs installés (de courant, de vitesse/position,…) implique un disfonctionnement de la commande conduisant dans la plupart du temps à la mise hors service du système. Ces conséquences sont contraires aux exigences des industriels qui demandent des degrés de fiabilité du système de plus en plus élevés. Des statistiques montrent que le défaut capteur est fréquent. Il est donc impératif de trouver des solutions pour assurer la continuité de service des systèmes électriques dans le cas de présence de ce type de défaut. Tout d'abord, l'étude présentée dans ce manuscrit présente les technologies des différents capteurs installés et ce pour comprendre les raisons et le type de pannes qui pourraient survenir. Ensuite, le système sur lequel la validation des algorithmes développés est décrit. Il s'agit d'un entraînement électrique basé sur une machine à Double Alimentation (MADA) fonctionnant en mode moteur et connectée au réseau via deux convertisseurs. La commande associée est une Commande Directe de Couple (CDC). Elle est validée en mode sain aussi bien par simulation qu'expérimentalement. Après, les études réalisées prennent en considération les défauts capteurs de courants alternatifs et de vitesse/position. Les algorithmes développés, permettant une continuité de service, utilisent une redondance analytique et sont basés sur l'estimation et aussi sur la Détection et l'Isolation d'un éventuel Défaut (DID). Ils sont caractérisés par leur simplicité. Aussi, ils ne sont pas gourmands en termes de consommation en ressources matérielles et leur temps d'exécution est très court. Enfin, la validation expérimentale de ces algorithmes montre bien leur efficacité en cas de défaut, vu que le système s'avère insensible au défaut et continue à fonctionner sans interruption. La commande obtenue est alors tolérante aux défauts capteurs. / The development of closed loop controls for electrical drives requires the sensor installations in order to get feed back information. Nevertheless, any occurred sensor fault (current sensor,speed/position sensor,…) shows an operation system deterioration which leads in most cases to its shut down. This consequence is in contrast to industrial expectations especially concerning the system high accuracy that they are asking for. Statistic studies point out the sensor faults as frequent. So, it is necessary to find out solutions ensuring the system service continuity in case of any sensor fault. Firstly, the study presented in this work shows the used sensor technologies in order to understand both of the reason and the kind of occurred faults. Secondly, the studied system is presented which is an electrical drive based on a Doubly Fed Induction Machine (DFIM) operating in motor mode and connected to the grid by two inverters. The control developed is a Direct Torque Control (DTC). The control validation, in healthy operating mode, is realised throw simulation and experimentally. After, a study considering alternative current sensor and speed/position sensor faults are achieved. The developed algorithms are based on signal estimation, on a Fault Detection Isolation (FDI) and reconfiguration algorithms. In fact, they are simple to carry out, they don't need much hardware resources for implementation and their execution time is short. Finally, the experimental validation of the developed algorithms shows their efficiency. The system continues working even in presence of a sensor fault. Thus, the obtained control becomes a fault tolerant control thanks to these algorithms.
17

Analýza pohonu modelu domovního výtahu s EC motorem / Drive model for EC motor elevator analysis

Javořík, Zdeněk January 2010 (has links)
The master thesis encompasses the possibilities of position evaluation and drive control with the aid of SMI work enviroment. Furthermore the thesis is directed to create a program through a designed control algorithm. The work is realised on the elevator model with electronically commuted motor. An incremental scanner is used as the position sensor. The motor control unit is set up and programmed in the SmartMotorInterface software. In the next part, measurements with altered parameters are conducted. On the basis of these measurements the influence of parameters on the positioning process and its accuracy is evaluated. At the conclusion of the work, a design of laboratory task for educational purposes is created. The laboratory task is composed in such a way, that students would become familiar with the SMI work enviroment and would be able to practicaly test the setup of incremental position sensor and motor control with the aid of entered algorithm.

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