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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.
31

Emulación de un aerogenerador conectado a la red a través de un sistema experimental Back-to-Back mediante la técnica "Hardware In The Loop"

Muñoz Jadán, Alexis Yanira January 2016 (has links)
Magíster en Ciencias de la Ingeniería, Mención Eléctrica / En la actualidad, el estudio de generación de electricidad por medio del recurso eólico es de gran importancia, por presentarse como solución para disminuir la contaminación ambiental al reemplazar los sistemas eléctricos a base de generación convencional por energía limpia. También, por constituir una vía de desarrollo para la sociedad al comunicarlo con la tecnología del mundo moderno. Sin embargo, debido a las dificultades que existen para realizar investigaciones de energía eólica con generadores reales, es necesario implementar prototipos que sean capaces de emular, aerogeneradores que serán utilizados en el trabajo de laboratorio. En este trabajo, mediante la técnica Hardware in the Loop , se logra en base a datos reales, emular el comportamiento de una turbina eólica en la plataforma de desarrollo Matlab/Simulink a través del sistema embebido que constituye el conversor de potencia en configuración Back-To-Back contenido en la unidad Triphase PM5F60R. Considerando perfiles de viento de distinta variabilidad con distintos valores medios y con un nivel de detalle adecuado de ingeniería, se estudia el desempeño de los sistemas de control correspondientes al aerogenerador, como: Pitch control y el algoritmo MPPT. En los cuáles se efectúan cambios en algunos parámetros importantes que caracterizan a las turbinas eólicas tales como: inercia, radio del aspa, curva aerodinámica, entre otros. Por otro lado, por medio de estrategias de control de corriente, basadas en múltiples controladores resonantes y amortiguamiento activo se logra compensar las resonancias causadas por los filtros LCL, inyectar corrientes con baja distorsión armónica y entregar potencia activa y reactiva variable a la red. Es así que, en este trabajo se identifican principalmente los siguientes aportes: Debido a que los aerogeneradores varían según su capacidad y modelo; mediante la técnica Hardware In The Loop ; se logra la emulación del aerogenerador y evita el uso de un aerogenerador real, otorgando flexibilidad en el diseño del mismo y su control. Así también, las estrategias de control de corriente por medio de controladores resonantes y metodología Active Damping, permite inyección de corriente a la red con baja distorsión armónica. Finalmente, la plataforma experimental implementada logra presentar un escenario cercano a la realidad de un sistema de generación eólica con conexión a la red por medio de un interface de electrónica de potencia. Su importancia radica debido a la validación de los resultados experimentales, en la habilidad para testear cada uno de los componentes que conforman el sistema implementado y realizar futuras investigaciones a cada uno de ellos de manera rigurosa. Así como también, es objeto de integración a otros sistemas, como por ejemplo, al de una micro-red en operación modo isla y modo red por medio de Droop Control.
32

Design and Hardware-in-the-Loop Testing of Optimal Controllers for Hybrid Electric Powertrains

Sharif Razavian, Reza January 2012 (has links)
The main objective of this research is the development of a flexible test-bench for evaluation of hybrid electric powertrain controllers. As a case study, a real-time near-optimal powertrain controller for a series hybrid electric vehicle (HEV) has been designed and tests. The designed controller, like many other optimal controllers, is based on a simple model. This control-oriented model aims to be as simple as possible in order to minimize the controller computational effort. However, a simple model may not be able to capture the vehicle's dynamics accurately, and the designed controller may fail to deliver the anticipated behavior. Therefore, it is crucial that the controller be tested in a realistic environment. To evaluate the performance of the designed model-based controller, it is first applied to a high-fidelity series HEV model that includes physics-based component models and low-level controllers. After successfully passing this model-in-the-loop test, the controller is programmed into a rapid-prototyping controller unit for hardware-in-the-loop simulations. This type of simulation is mostly intended to consider controller computational resources, as well as the communication issues between the controller and the plant (model solver). As the battery pack is one of the most critical components in a hybrid electric powertrain, the component-in-the-loop simulation setup is used to include a physical battery in the simulations in order to further enhance simulation accuracy. Finally, the driver-in-the-loop setup enables us to receive the inputs from a human driver instead of a fixed drive cycle, which allows us to study the effects of the unpredictable driver behavior. The developed powertrain controller itself is a real-time, drive cycle-independent controller for a series HEV, and is designed using a control-oriented model and Pontryagin's Minimum Principle. Like other proposed controllers in the literature, this controller still requires some information about future driving conditions; however, the amount of information is reduced. Although the controller design procedure is based on a series HEV with NiMH battery as the electric energy storage, the same procedure can be used to obtain the supervisory controller for a series HEV with an ultra-capacitor. By testing the designed optimal controller with the prescribed simulation setups, it is shown that the controller can ensure optimal behavior of the powertrain, as the dominant system behavior is very close to what is being predicted by the control-oriented model. It is also shown that the controller is able to handle small uncertainties in the driver behavior.
33

Commande d'un système de puissance électrique pour de personne à mobilité réduite

Ciarla, Valentina 10 October 2013 (has links) (PDF)
Ce travail s'inscrit dans le contexte général des nouvelles générations de Direction Assistée Electrique (DAE ou EPAS en anglais pour Electronic Power Assistance Steering), dont l'objectif est de tenir compte des caractéristiques des conducteurs à mobilité réduite. En effet, à ce jour, il n'existe pas de système de direction assistée adapté aux capacités articulaires (rhumatismes divers), musculaires (diminution de force, sénescence), ou encore aux douleurs ressenties par le conducteur, ce qui constitue une insuffisance dès lors que l'on s'intéresse à de telles populations. Le principal objectif de cette thèse est donc de proposer une méthodologie générale permettant d'adapter une DAE standard aux conducteurs à mobilité réduite. La méthodologie proposée a été validé sur une plateforme de type Hardware-In the Loop et les résultats expérimentaux obtenus mettent bien en évidence l'intérêt de la démarche proposée. Ils représentent également un point de départ pour l'implantation de l'aide envisagée sur un véhicule réel et jettent les bases pour l'application de la méthodologie à une large classe de patients affectés par des pathologies différentes.
34

Design and Hardware-in-the-Loop Testing of Optimal Controllers for Hybrid Electric Powertrains

Sharif Razavian, Reza January 2012 (has links)
The main objective of this research is the development of a flexible test-bench for evaluation of hybrid electric powertrain controllers. As a case study, a real-time near-optimal powertrain controller for a series hybrid electric vehicle (HEV) has been designed and tests. The designed controller, like many other optimal controllers, is based on a simple model. This control-oriented model aims to be as simple as possible in order to minimize the controller computational effort. However, a simple model may not be able to capture the vehicle's dynamics accurately, and the designed controller may fail to deliver the anticipated behavior. Therefore, it is crucial that the controller be tested in a realistic environment. To evaluate the performance of the designed model-based controller, it is first applied to a high-fidelity series HEV model that includes physics-based component models and low-level controllers. After successfully passing this model-in-the-loop test, the controller is programmed into a rapid-prototyping controller unit for hardware-in-the-loop simulations. This type of simulation is mostly intended to consider controller computational resources, as well as the communication issues between the controller and the plant (model solver). As the battery pack is one of the most critical components in a hybrid electric powertrain, the component-in-the-loop simulation setup is used to include a physical battery in the simulations in order to further enhance simulation accuracy. Finally, the driver-in-the-loop setup enables us to receive the inputs from a human driver instead of a fixed drive cycle, which allows us to study the effects of the unpredictable driver behavior. The developed powertrain controller itself is a real-time, drive cycle-independent controller for a series HEV, and is designed using a control-oriented model and Pontryagin's Minimum Principle. Like other proposed controllers in the literature, this controller still requires some information about future driving conditions; however, the amount of information is reduced. Although the controller design procedure is based on a series HEV with NiMH battery as the electric energy storage, the same procedure can be used to obtain the supervisory controller for a series HEV with an ultra-capacitor. By testing the designed optimal controller with the prescribed simulation setups, it is shown that the controller can ensure optimal behavior of the powertrain, as the dominant system behavior is very close to what is being predicted by the control-oriented model. It is also shown that the controller is able to handle small uncertainties in the driver behavior.
35

Alcaloides e glicosídeo flavonoídico de Waltheria viscosissima A. St. Hil - Malvaceae

Rolim, Yngred Mangueira 10 August 2015 (has links)
Submitted by Clebson Anjos (clebson.leandro54@gmail.com) on 2016-03-30T20:42:37Z No. of bitstreams: 1 arquivototal.pdf: 1814716 bytes, checksum: a26c5822d97b7f1b0b306ae1dd8adf49 (MD5) / Made available in DSpace on 2016-03-30T20:42:37Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1814716 bytes, checksum: a26c5822d97b7f1b0b306ae1dd8adf49 (MD5) Previous issue date: 2015-08-10 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The tradition of consumption of medicinal plants is one of the oldest practices of humanity and in the Brazilian scenario plants play an important role in folk medicine, not only for its food character, but also for its healing properties, whether for scientific grounds or by popular beliefs, knowledge of its chemical constituents, pharmacological activities and mechanism of action are open for proving the efficacy and its safe use. The Waltheria viscosissima A. St. Hil. Is a species belonging to Malvaceae family popularly known as viscosa malva. Listed in popular medicine to expectorant action, antitussive, anti-hypertensive, maturativa of tumors and for the treatment of ulcers. The phytochemical study of the phase ethyl acetate ethanol extract partitioning of Waltheria viscosissima A. St. Hil. and the phases obtained from the alkaloids gear through column chromatographic techniques led to the isolation of three substances: tilirosídeo (Wv-1), a mixture of waltheriona wlatheriona A and B (Wv-2). The structural identification of these substances were performed by spectroscopic methods using nuclear magnetic resonance IR and 1H and 13C, with the aid of single- and two-dimensional techniques, as well as by comparisons with literature data. / A tradição do consumo de plantas medicinais é uma das práticas mais antigas da humanidade e no cenário brasileiro as plantas desempenham um importante papel na medicina popular, não apenas por seu caráter alimentar, mas também por suas propriedades de cura, sejam elas com fundamentos científicos ou por crendices populares. O conhecimento dos seus constituintes químicos, atividades farmacológicas e mecanismo de ação são a abertura para comprovação da eficácia e o seu uso seguro. A Waltheria viscosissima A. St. Hil. é uma espécie pertencente a família Malvaceae conhecida popularmente como malva viscosa. Apontada pela medicina popular com ação expectorante, antitussígena, anti-hipertensiva, maturativa de tumores e para o tratamento de úlceras. O estudo fitoquímico realizado com a fase acetato de etila do particionamento do Extrato Etanólico Bruto da Waltheria viscosissima A. St. Hil. e as fases obtidas da marcha de alcaloides através de técnicas cromatograficas em coluna, levou ao isolamento de três substâncias: tilirosídeo (Wv-1), uma mistura de waltheriona A e wlatheriona B (Wv-2). A identificação estrutural dessas substâncias foi realizada através de métodos espectroscópicos utilizando o Infravermelho e a Ressonância Magnética Nuclear de 1H e 13C, com o auxílio das técnicas uni e bidimensionais, como também por comparações realizadas com modelos da literatura.
36

Caracterização e diversidade genética de frutos de cajuzinho-do-cerrado / Characterization and genetic diversity of fruits of cajuzinho-do-cerrado

Pereira, Laísse Danielle 03 July 2018 (has links)
Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2018-08-14T13:14:02Z No. of bitstreams: 2 Dissertação - Laísse Danielle Pereira - 2018.pdf: 1521237 bytes, checksum: 35c856d7e5b093781126cf1fbc858e2c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-08-16T11:22:48Z (GMT) No. of bitstreams: 2 Dissertação - Laísse Danielle Pereira - 2018.pdf: 1521237 bytes, checksum: 35c856d7e5b093781126cf1fbc858e2c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-08-16T11:22:48Z (GMT). No. of bitstreams: 2 Dissertação - Laísse Danielle Pereira - 2018.pdf: 1521237 bytes, checksum: 35c856d7e5b093781126cf1fbc858e2c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-07-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Aiming to characterize and evaluate the genetic diversity of cajuzinho-do-cerrado, in the 2016 harvest, three studies were conducted based on flowering characteristics and physical and chemical characteristics of cashew nuts and cashew apples. The works were conducted in the "ex situ" biological collection of Anacardium humile A. St.-Hil. and in the laboratory of genetics and molecular biology, both at the Universidade Federal de Goiás – Regional Jataí. For the first study, flowering characteristics of the accessions of the collection were evaluated. The results were submitted to the descriptive and multivariate analysis of the genetic diversity. For the second and third study, physical and chemical characteristics of cashew apples and cashew nuts (from 5 to 15 per access) were evaluated. In the second, the results were submitted to the descriptive analysis for each access and Pearson correlation among the variables measured. In the third, besides the descriptive analysis for the variables, the results were submitted to the multivariate analysis. Diversity was observed with bases on the attributes of flowering and fruiting, where the UPGMA dendrogram and Tocher method were efficient to demonstrate this diversity. The accessions from Serranópolis presented high values of number of flowers and percentage of flowering acess. Access 1 presented higher values for cashew nut size and higher access and vitamin C content of cashew apple, with vitamin C being significantly correlated with epidermal and pulp tonality, soluble solids content and cashew nut length. / Objetivando-se caracterizar e avaliar a diversidade genética de Cajuzinho-do-cerrado, na safra de 2016, foram conduzidos três estudos. Estes foram conduzidos na coleção biológica “ex situ” de Anacardium humile A. St.- Hil. e no Laboratório de Genética e Biologia Molecular, ambos na Universidade Federal de Goiás - Regional Jataí. Para o primeiro estudo foram avaliadas características da floração dos acessos da coleção. Os resultados foram submetidos à análise descritiva e multivariada. Para o segundo e terceiro estudos foram avaliadas características físicas e químicas dos pseudofrutos e frutos (de 5 a 15 por acesso). No segundo os resultados foram submetidos à análise descritiva para cada acesso e correlação de Pearson entre as variáveis mensuradas. No terceiro estudo, além da análise descritiva para as variáveis, os resultados foram submetidos à análise multivariada. Observou-se existência diversidade com bases nos atributos do florescimento e frutificação, onde, o dendrograma UPGMA e Método de Otimização de Tocher foram eficientes para demonstrar essa diversidade. Os acessos procedentes de Serranópolis apresentaram valores elevados de número de flores e percentual de acessos floridos. O acesso 1 apresentou valores superiores para as dimensões do fruto e o acesso 3 maior e teor de vitamina C do pseudofruto, sendo que a vitamina C obteve correlação significativa com a tonalidade da epiderme e da polpa, teor de sólidos solúveis e comprimento do fruto.
37

HIL simulace manipulátorů nebo stroje / HIL simulation of manipulators or machines

Dočekal, Martin January 2021 (has links)
The diploma thesis deals with HIL simulation (hardware in the loop). The thesis contains a manipulator created in the virtual software V-REP. The connection of real inputs and virtual outputs of the machine is realized by the microcontroller Arduino UNO. The first task deals with the control of the manipulator using the joystick PS2. The second task is a separate control of the robot using an microcontroller Arduino UNO. The resulting connection can be modified in the furher and the interface modified. The work will be used for educational purposes.
38

Multi-modal Simulation and Calibration for OSU CampusMobility

Kalra, Vikhyat January 2021 (has links)
No description available.
39

Methodology for Real Time Simulations of Autonomous Utility Vehicles

Borgström, Johan January 2020 (has links)
This master thesis is a part of a research project where Luleå University of Technology (LTU) collaborates with University of Oulu, SINTEF Narvik and Oulu University of Applied Sciences. The goal with the research project is to develop a Nordic platform for development of autonomous, environmental friendly and energy efficient heavy vehicles in the forest, harbor and mining industry. The purpose with the master thesis is to assist LTU in their role in the research project. The Nordic platform was positioned in the product development process, with the result that it could be useful in the fourth phase ”Detail design” and in the fifth phase ”Testing and refinement” in the Ulrich and Eppinger product development process. A methodology has been developed, covering all necessary steps going from an assembly of a vehicle in an arbitrary CAD program to perform real time simulations (including HiL simulations) of the vehicle in Simulink. The off-road research platform for forest- and agriculture applications developed by LTU was used as a case study in the master thesis. Applying the methodology on this platform showed that choosing correct simulation frequency is important and that graphics enabled in real time simulations requires large computational power.
40

Modeling and Performance Analysis of a 10-Speed Automatic Transmission for X-in-the-Loop Simulation

Thomas, Clayton Austin 11 December 2018 (has links)
No description available.

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