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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

A deformable terrain model in multi-domain dynamics using elastoplastic constraints: An adaptive approach / Modellering av deformerbar terräng med elastoplastiska bivillkor i flerkroppsdynamik: Ett adaptivt tillvägagångssätt

Agvik, Simon January 2015 (has links)
Achieving realistic simulations of terrain vehicles in their work environment does not only require a careful model of the vehicle itself but the vehicle's interactions with the surroundings are equally important. For off-road ground vehicles the terrain will heavily affect the behaviour of the vehicle and thus puts great demands on the terrain model. The purpose of this project has been to develop and evaluate a deformable terrain model, meant to be used in real-time simulations with multi-body dynamics. The proposed approach is a modification of an existing elastoplastic model based on linear elasticity theory and a capped Drucker-Prager model, using it in an adaptive way. The original model can be seen as a system of rigid bodies connected by elastoplastic constraints, representing the terrain. This project investigates if it is possible to create dynamic bodies just when it is absolutely necessary, and store information about possible deformations in a grid. Two methods used for transferring information between the dynamic bodies and the grid have been evaluated; an interpolating approach and a discrete approach. The test results indicate that the interpolating approach is preferable, with better stability to an equal performance cost. However, stability problems still exist that have to be solved if the model should be useful in a commercial product.
2

Modeling and Hardware-in-the-loop Simulations of Contactor Dynamics : Mechanics, Electromagnetics and Software / Modellering och hardware-in-the-loopsimulering av kontaktordynamik : Mekanik, elektromagnetism och mjukvara

Tjerngren, Jon January 2014 (has links)
This master thesis’s subject is to model an ABB contactor’s dynamics and to develop a hardware-in-the-loop simulation environment. The hardware-in-the-loop method utilizes computer models that are simulated in a real-time simulator. The real-time simulator is connected to hardware components. A contactor is an electrically controlled mechanical switching device and it is used in circuits where large currents can occur. In this thesis, the contactor is divided into three separate subsystems and models are developed for each of them. The three subsystems correspond to the contactor’s mechanics, electromagnetics and electronic components. Computer models are implemented in MATLAB and Simulink to realize the subsystems. The hardware part, of the hardware-in-the-loop simulations, consists of electronic parts that are not modeled. To connect the hardware part to a real-time simulator, from dSPACE, a hardware interface was constructed. This report focuses on the modeling of the mechanics and the electromagnetics as well as the software implementations. The thesis work was carried out in collaboration with another student. The focuses of his report are the modeling of the electronics and the construction of the hardware interface. Validation of the hardware-in-the-loop simulations is done by using measurements collected from a real contactor. The conclusion is that the simulations of the contactor’s behavior correspond well with a real contactor.
3

A Hardware-in-the-Loop Test Platform for Planetary Rovers

Yue, Bonnie January 2011 (has links)
Hardware-in-the-Loop (HIL) test platform for planetary rovers was designed, fabricated and tested in the present work. The ability for planetary rover designers and mission planners to estimate the rover’s performance through software simulation is crucial. HIL testing can further the benefits of software simulations by allowing designers to incorporate hardware components within traditionally pure software simulations. This provides more accurate performance results without having access to all hardware components, as would be required for a full prototype testing. The test platform is designed with complete modularity such that different types of tests can be performed for varying types of planetary rovers and in different environments. For demonstrating the operation of the test platform, however, the power system operation of a solar powered rover was examined. The system consists of solar panels, a solar charge controller, a battery, a DC/DC converter, a DC motor and a flywheel. In addition, a lighting system was designed to simulate the solar radiation conditions solar panels would experience throughout a typical day. On the software side, a library of component models was developed within MapleSim and model parameters were tuned to match the hardware on the test bench. A program was developed for real-time simulations within Labview allowing communication between hardware components and software models. This program consists of all the component models, hardware controls and data acquisitioning. The GUI of this program allows users to select which component is to be tested and which component is to be simulated, change model parameters as well as see real time sensor measurements for each component. A signal scaling technique based on non-dimensionalization is also presented, which can be used in an HIL application for obtain scaling factors to ensure dynamic similarity between two systems. A demonstration of power estimation was performed using the pure software model simulations as well as the pure hardware testing. Hardware components were then added into the software simulation progressively with results showing better accuracy as hardware is added. The rover’s power flow was also estimated under different load conditions and seasonal variation. These simulations clearly demonstrate the effectiveness of an HIL platform for testing a rover’s hardware performance.
4

A Hardware-in-the-Loop Test Platform for Planetary Rovers

Yue, Bonnie January 2011 (has links)
Hardware-in-the-Loop (HIL) test platform for planetary rovers was designed, fabricated and tested in the present work. The ability for planetary rover designers and mission planners to estimate the rover’s performance through software simulation is crucial. HIL testing can further the benefits of software simulations by allowing designers to incorporate hardware components within traditionally pure software simulations. This provides more accurate performance results without having access to all hardware components, as would be required for a full prototype testing. The test platform is designed with complete modularity such that different types of tests can be performed for varying types of planetary rovers and in different environments. For demonstrating the operation of the test platform, however, the power system operation of a solar powered rover was examined. The system consists of solar panels, a solar charge controller, a battery, a DC/DC converter, a DC motor and a flywheel. In addition, a lighting system was designed to simulate the solar radiation conditions solar panels would experience throughout a typical day. On the software side, a library of component models was developed within MapleSim and model parameters were tuned to match the hardware on the test bench. A program was developed for real-time simulations within Labview allowing communication between hardware components and software models. This program consists of all the component models, hardware controls and data acquisitioning. The GUI of this program allows users to select which component is to be tested and which component is to be simulated, change model parameters as well as see real time sensor measurements for each component. A signal scaling technique based on non-dimensionalization is also presented, which can be used in an HIL application for obtain scaling factors to ensure dynamic similarity between two systems. A demonstration of power estimation was performed using the pure software model simulations as well as the pure hardware testing. Hardware components were then added into the software simulation progressively with results showing better accuracy as hardware is added. The rover’s power flow was also estimated under different load conditions and seasonal variation. These simulations clearly demonstrate the effectiveness of an HIL platform for testing a rover’s hardware performance.
5

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.
6

Investigation into Air Traffic Complexity as a Driver of a Controller‘s Workload

Djokic, Jelena 24 August 2016 (has links) (PDF)
The thesis describes an investigation into Air Traffic Control (ATC) complexity as a contributory factor in changes of controllers' workload. It is considered that ATC complexity, together with equipment interface and procedural demands comprise the task demands imposed on the en-route controller to perform certain activities, which mediated by performance shaping factors create workload. The data used to study this relationship came from ATC real-time simulations completed at EUROCONTROL CRDS in Budapest: recorded flown trajectories, communication performed by the controller (whether with other controllers or with the pilots), data entries related to flight data management, and instantaneous self-assessment ratings of workload provided by the controllers were used. The ATC complexity factors that have been consistently found to be important in the previous studies (related to aircraft density, flight attributes of each individual aircraft, aircraft conflicts and traffic disorder) and for which detailed calculation formula have been reported were selected for further analysis. Since the established set of factors resulted from multiple researches conducted in this field, it was assumed that some of these factors are correlated with one another, overlapping and possibly measuring similar concepts. Therefore, a reduction of the initial set of factors was performed by combining information contained within these factors into a smaller number of new artificial variables and by deleting statistically redundant portions of these factors prior to conducting further analysis. The Principal Component Analysis (PCA), which is the statistical method applied to achieve required reduction, resulted in the overall set of 6 complexity components, whose interpretations are driven by the factors that showed the strongest correlation with that component. In order to establish a link between ATC complexity and a controller's subjective workload, multiple regression analysis was performed, using the complexity components identified in the PCA as predictors of the workload ratings. In addition, some measures of controller’s activity (data entries made by the controllers related to flight data management, cumulative duration of radio calls, i.e. frequency occupancy time, and average duration of single calls) were added to the analysis to test whether information about the controller’s activity could be also useful for predicting workload, once the effect of complexity had been considered, and to verify whether the effect of complexity on workload could be mediated by the effect of complexity on the controller’s activity. The analysis revealed that both ATC complexity and the activities that the controller performs to deal with a demand imposed on him/her give a unique contribution to the prediction of workload ratings and therefore the workload of the controller is determined by both ATC complexity and controller’s activities. In addition, it was assumed that the workload is differently impacted by individual components of complexity, and further statistical analyses were performed to test this assumption. Understanding these differences could in fact facilitate comparison of the complexity levels of a single sector under different conditions, but also comparison of complexity levels of different sectors under same conditions. Firstly the changes in the workload and activities of the controllers under different conditions were investigated using analysis of variance. Subsequently, in order to be able to map these changes on the complexity components, it was necessary also to investigate into the changes that the complexity components undergo when observed under different conditions. The results revealed different behaviour of single complexity components when mapped on the changes recorded in the activities of the controller and workload, demonstrating that changes in controller’s activities and perceived workload are driven by different complexity components in different sectors and under different operational conditions. Shedding light on these contributors to the workload experienced by a controller can greatly facilitate the introduction of any change envisaged for the airspace under consideration. Namely, in the current structure, whenever new procedures or new working methods are subject to possible deployment, the identified complexity components could support the estimation of the impact that those changes would impose on the workload of the controller and further on decision making processes. Additionally, the complexity components are also applicable in the validation of the new concepts and new technologies to be introduced in the system when designing simulation scenarios against which new concepts would be assessed. As also demonstrated by the analysis, the comparison of different sectors, or even different sector designs within the same airspace, could be compared and contribute to the improvement of airspace design. / Die vorliegende Arbeit untersucht die Komplexität der Flugverkehrskontrolle (Air Traffic Control, ATC) als einen wesentlichen Einflussfaktor auf die Arbeitsbelastung des Radarlotsen. Die zentrale Annahme ist dabei, dass die Komplexität der ATC zusammen mit den Anforderungen aus den betrieblichen Rahmenbedingungen (technische Systemschnittstellen und Prozeduren) den Lotsen zu bestimmten Abläufen zwingen, welche die Arbeitsbelastung signifikant beeinflussen. Für die durchgeführten Untersuchungen standen Daten von ATC-Echtzeitsimulationen von EUROCONTROL CRDS Budapest zur Verfügung, die folgende Informationen umfassen: abgeflogene Flugtrajektorien, Kommunikationsprotokolle der Lotsen (untereinander oder zwischen Lotse und Pilot), Daten aus dem flight-data Management und Daten aus der regelmäßigen Selbstbewertung der Lotsen bezüglich ihrer aktuell gefühlten Arbeitsbelastung. Die bereits in früheren Studien identifizierten Komplexitätsvariablen (insbesondere die lokale Flugzeugdichte, spezifische Flugzeugeigenschaften, Konfliktsituationen zwischen Flugzeugen und die Verkehrslage betreffend) sowie hierzu erarbeitete mathematische Vorschriften bilden die Grundlage für die weiterführenden, detaillierten Untersuchungen. Aufgrund der Vielzahl an Komplexitätsvariablen aus diversen wissenschaftlichen Quellen war davon auszugehen, dass Korrelationen unter den Variablen vorliegen. Aus diesem Grund wurden zunächst statistisch redundante Informationen der ursprünglich vorliegenden Variablen reduziert, sodass als Ergebnis neue voneinander unabhängige Faktoren klassifiziert werden konnten. Die hierfür verwendete Hauptkomponentenanalyse (Principal Component Analysis - PCA) führte zu sechs statistisch signifikanten Komplexitätsfaktoren, die anhand der höchsten Korrelation zur zugeordneten Komponente interpretiert wurden. Um die Verbindung zwischen der ATC Komplexität und der subjektiv empfundenen Arbeitsbelastung herzustellen, wurde eine multiple Regressionsanalyse zwischen den Komplexitätsfaktoren und den abgeleiteten Arbeitsbelastungszuständen durchgeführt. Zusätzlich lagen für die Analyse der Arbeitsbelastung auch Daten über die Arbeitsaufgaben des Lotsen vor (bspw. Dateneinträge des Lotsen, Gesamtlänge der Funkanweisungen, durchschnittliche Länge der Funkanweisungen), um zu untersuchen, inwieweit sich aus den aktuell durchgeführten Arbeitsaufgaben bei gegebener Verkehrsnachfrage eine verlässliche Vorhersage über die Arbeitsbelastung ableiten lässt. Die Analyse zur Vorhersage der Arbeitsbelastung konnte zeigen, dass sowohl die ATC Komplexität als auch die aktuellen Arbeitsaufgaben einen individuellen und signifikanten Einfluss haben. Weiterhin wurde unterstellt, dass die spezifischen Komplexitätsfaktoren einen unterschiedlichen Effekt auf die Arbeitsbelastung ausüben. Die Überprüfung dieser Annahme war ebenfalls Bestandteil der umfangreichen statistischen Untersuchungen. Tatsächlich könnte ein fundamentales Verständnis der Komplexitätsgrade den Vergleich einzelner Luftraumsektoren unter verschiedenen operativen Randbedingungen, als auch den Vergleich unterschiedlicher Luftraumsektoren mit vergleichbaren operativen Randbedingungen wesentlich erleichtern. Zuerst wurden die Veränderungen der Arbeitsbelastung und -die Tätigkeiten der Lotsen unter Verwendung einer Varianzanalyse untersucht. Um eine valide Zuordnung zu den Komplexitätsfaktoren sicherzustellen, war es ebenfalls notwendig, die Veränderungen dieser Faktoren und Tätigkeiten unter wechselnden Randbedingungen zu analysieren. Die Analysen zeigen hierbei unterschiedliche Resultate bezüglich der jeweiligen Komplexitätsfaktoren. So beeinflussen die verschiedenen Komplexitätsfaktoren die Handlungsabläufe der Lotsen und die wahrgenommene Arbeitsbelastung, jedoch in Abhängigkeit von den ausgewählten Sektoren und den betrieblichen Randbedingungen. Unter Berücksichtigung dieser erarbeiteten Abhängigkeiten der Arbeitsbelastung des Lotsen können nun die Auswirkungen von Veränderungen im Luftraum zuverlässig bestimmt werden. Gerade in Bezug auf Veränderungen der gegenwärtigen Luftraumstruktur oder die Einführung neuer Prozeduren oder Arbeitsabläufe können die entwickelten Komplexitätsfaktoren bereits frühzeitig Aufschluss darüber geben, welche Konsequenzen solche Veränderungen auf die Arbeitsbelastung der Lotsen nach sich ziehen können und Entscheidungsprozesse unterstützen. Weiterhin sind die entwickelten Komplexitätsfaktoren als Grundlage für die Validierung neuer Konzepte und Technologien, gegebenenfalls unter Verwendung von entwickelten Simulationsszenarien, nutzbar. Darüber hinaus können die Komplexitätsfaktoren für die Gegenüberstellung von verschiedenen Luftraumsektoren genutzt werden und zur Abwägung bzw. Optimierung von Entwürfen eines Luftraumdesigns dienen.
7

Power Electronics for Mitigation of Voltage Sags and Improved Control of AC Power Systems

Magalhães de Oliveira, Marcio January 2000 (has links)
The thesis deals with the application of compensators andswitches based on power electronics in AC transmission anddistribution systems. The objective of the studieddevices/equipment is the power flow and voltage control intransmission systems and the mitigation of voltage sags andmomentary interruptions to critical loads in distributionsystems. For validating the power electronics based devices/equipmentdescribed in the thesis, scaled models at a real-time simulatorhave been built. Simulation results of these models arepresented and discussed in the thesis. The equipment studied in the thesis exploit the fast controlactions that can be taken by power electronics devices, whichare much faster than the speed of conventional equipment andprotection systems, based on electromechanical devices. In thisway, the power quality of distribution systems is improved,regarding duration and magnitude of voltage sags (dips) andmomentary interruptions, which are the most relevant types ofdisturbances in distribution systems. The thesis presents some compensators based onforced-commutation voltage-source converters for correctingvoltage sags and swells to critical loads. The seriesconverter, usually denoted Dynamic Voltage Restorer (DVR), hasbeen proved suitable for the task of compensating voltage sagsin the supply network. The use of solid-state devices ascircuit breakers in distribution systems has also been studiedwith the objective of achieving fast interruption or limitationof fault currents. The location and practical aspects for theinstallation of these solid-state breakers are presented. Ithas beenshown that a configuration based on shunt and seriesconnected solid-state devices with controllable turn-offcapability can also provide voltage sag mitigation, without theneed of transformers and large energy storage elements. The operation and control of two Flexible AC TransmissionSystem (FACTS) devices for voltage and power flow control intransmission systems, namely the Static Synchronous Compensator(STATCOM) and the Unified Power Flow Controller (UPFC),respectively, are also studied. A faster response compared totraditional equipment consisting of mechanically based/switchedelements is then achieved. This allows a more flexible controlof power flow and a secure loading of transmission lines tolevels nearer to their thermal limits. The behaviour of thesedevices during faults in the transmission system is alsopresented. Keywords: power electronics, power quality, voltagesags, voltage-source converters, Custom Power, FACTS, real-timesimulations, solid-state devices.
8

Power Electronics for Mitigation of Voltage Sags and Improved Control of AC Power Systems

Magalhães de Oliveira, Marcio January 2000 (has links)
<p>The thesis deals with the application of compensators andswitches based on power electronics in AC transmission anddistribution systems. The objective of the studieddevices/equipment is the power flow and voltage control intransmission systems and the mitigation of voltage sags andmomentary interruptions to critical loads in distributionsystems.</p><p>For validating the power electronics based devices/equipmentdescribed in the thesis, scaled models at a real-time simulatorhave been built. Simulation results of these models arepresented and discussed in the thesis.</p><p>The equipment studied in the thesis exploit the fast controlactions that can be taken by power electronics devices, whichare much faster than the speed of conventional equipment andprotection systems, based on electromechanical devices. In thisway, the power quality of distribution systems is improved,regarding duration and magnitude of voltage sags (dips) andmomentary interruptions, which are the most relevant types ofdisturbances in distribution systems.</p><p>The thesis presents some compensators based onforced-commutation voltage-source converters for correctingvoltage sags and swells to critical loads. The seriesconverter, usually denoted Dynamic Voltage Restorer (DVR), hasbeen proved suitable for the task of compensating voltage sagsin the supply network. The use of solid-state devices ascircuit breakers in distribution systems has also been studiedwith the objective of achieving fast interruption or limitationof fault currents. The location and practical aspects for theinstallation of these solid-state breakers are presented. Ithas beenshown that a configuration based on shunt and seriesconnected solid-state devices with controllable turn-offcapability can also provide voltage sag mitigation, without theneed of transformers and large energy storage elements.</p><p>The operation and control of two Flexible AC TransmissionSystem (FACTS) devices for voltage and power flow control intransmission systems, namely the Static Synchronous Compensator(STATCOM) and the Unified Power Flow Controller (UPFC),respectively, are also studied. A faster response compared totraditional equipment consisting of mechanically based/switchedelements is then achieved. This allows a more flexible controlof power flow and a secure loading of transmission lines tolevels nearer to their thermal limits. The behaviour of thesedevices during faults in the transmission system is alsopresented. Keywords: power electronics, power quality, voltagesags, voltage-source converters, Custom Power, FACTS, real-timesimulations, solid-state devices.</p>
9

Développement de la gestion optimale de l'énergie électrique dans les îles Galápagos vers les Reséaux Intelligents / Development of optimal energy management in Galapagos Islands towards Smart Grid

Morales jadan, Diego 18 December 2017 (has links)
Les îles Galápagos sont un archipel d'îles volcaniques situées dans l'océan Pacifique, à 926 km à l'ouest de l'Equateur continental, dont elles font partie. Depuis 1978, les îles Galápagos sont déclarées patrimoine mondial. En raison de la croissance de la population, il existe plusieurs problèmes sociaux, économiques et environnementaux qui risquent la conservation de l'environnement des îles. Dans ce contexte, le gouvernement équatorien veut préserver son patrimoine écologique. Par conséquence, avec la participation de divers acteurs, principalement le ministère de l'Énergie et des Énergies renouvelables, il effectue plusieurs initiatives. Afin d'améliorer les services fournis sur les îles, cet objectif sera accompli grâce à la réduction de la consommation de carburants fossiles et donc des émissions de CO2. Donc, cette thèse a analysé l'impact des nouveaux services sur le réseau électrique, comme le remplacement obligatoire des véhicules conventionnels et des cuisinières pour des solutions efficaces et la proposition des solutions pour réduire les problèmes négatifs sur le réseau. En outre, une forte intégration de la génération distribuée a été considérée dans l'analyse. De plus, des solutions innovantes pour basse et moyenne tension ont été conçues et testées afin d’améliorer le service électrique sans affecter l'environnement et conserver ce patrimoine mondial. Par exemple, un programme DSM intelligent composé d'un schéma de temps d'utilisation (TOU) combiné avec la réponse de la demande (DR) a montré des résultats intéressants, l'installation d'un système de stockage d'énergie de batterie a également été testée, et les résultats de moyenne tension sont prometteurs. Un système de commutation automatique de phase a été adapté comme une solution pour réduire le déséquilibre en basse tension avec des résultats impressionnants. Le déploiement des réenclencheurs a démontré une amélioration considérable de la fiabilité avec un retour d’investissement très court. Considérant les technologies de l'information et de la communication, une pièce clé pour déployer Smart Grids, l'architecture de communication des réseaux de NAN/FAN/HAN a été abordée. Enfin, un Système de Gestion d’Energie pour la gestion optimale de l'énergie à Galápagos a été conçu. Toutes ces études représentent un défi important : la gestion optimale de l'électricité de réseau isolée sans énergie fossile. / The Galápagos Islands are an archipelago of volcanic islands located in the Pacific Ocean, 926 km west of continental Ecuador, of which they are a part. Since 1978, Galapagos Islands are accepted as Heritage World, due to the growth of the population, there are several social, economic and environmental problems, which endanger the environment conservation of the Islands.In this context, the Ecuadorian government desires to preserve its ecological heritage. Hence, with the participation of several stakeholders mainly the Ministry of Energy and Renewable Energy, it is releasing a lot of initiatives. In order to improve the general services that are provided in the islands, this goal will be achieved by means of reducing fossil fuel consumption and therefore CO2 emissions. Thus, this thesis has analyzed the impact of new services on the grid such as the mandatory replacement of conventional vehicles and cookers for efficient ones and to propose solutions for reducing negative issues originated on the network. Also, a strong integration of distributed generation is considered in the analysis.In addition, innovative solutions for both low and medium voltage have been designed and tested for improving the electrical service without affecting the environment and conserving this world heritage. For instance, a smart DSM program composed of Time of Use scheme combined with Demand Response has shown interesting results, the installation of a Battery Energy Storage System has been studied as well; the results in Medium Voltage are promising. An Automatic Phase Switching system is adapted like a solution for reducing unbalance in low voltage with impressive results. The deployment of reclosers has demonstrated a considerable improvement in the reliability with a Return on Investment very short.Considering the Information and Communication Technologies a key piece to deploy Smart Grids, the communication architecture of the Neighbor, Field and Home Area Networks is addressed. As last, an Energy Management System for performing optimal energy management within Galapagos is designed. All these studies have a significant challenge: the optimal management of electricity of isolated grid with zero fossil energy.
10

Filtros digitais recursivos para redução do impacto da resposta transitória do TPC.

SILVA, Célio Anésio da. 13 December 2017 (has links)
Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2017-12-13T16:54:10Z No. of bitstreams: 1 CÉLIO ANÉSIO DA SILVA - TESE (PPGEE) 2014.pdf: 1651226 bytes, checksum: a70dc4864a551f419c02ff41303eaffc (MD5) / Made available in DSpace on 2017-12-13T16:54:11Z (GMT). No. of bitstreams: 1 CÉLIO ANÉSIO DA SILVA - TESE (PPGEE) 2014.pdf: 1651226 bytes, checksum: a70dc4864a551f419c02ff41303eaffc (MD5) Previous issue date: 2014-05-29 / Capes / Um novo método de obtenção de parâmetros de filtros digitais recursivos (FDR) é apresentado para reduzir o impacto da resposta transitória dos Transformadores de Potencial Capacitivos (TPC) sobre o desempenho dos sistemas de medição, proteção e controle. Assumindo uma topologia predefinida, os parâmetros dos filtros são obtidos a partir da resposta em frequência do TPC de interesse. Diferentemente das técnicas reportadas na literatura, o método se aplica com facilidade a TPC de diferentes classes de tensão e independe das características operacionais do sistema. Para tanto, faz-se necessário conhecer a resposta em frequência do TPC em questão, no espectro de frequência de interesse. A validação do método é realizada através de simulações digitais em tempo real via simulador RTDSTM (Real Time Digital Simulator). As análises são baseadas em dados de sistemas elétricos reais e no funcionamento dinâmico dos filtros através da estimação dos fasores das tensões e estudos de localização de falta. A partir dos resultados obtidos, verifica-se que a presença dos FDR reduz significativamente os erros de medição causados pelos TPC quando submetidos a condições transitórias. Portanto, os FDR surgem como uma forma simples e de baixo custo para melhorar o desempenho e a confiabilidade dos sistemas de medição, proteção e controle. / A new method for obtaining recursive digital filter (FDR) parameters is presented in order to reduce the impact of Coupling Capacitor Voltage Transformer (CCVT) transient response on the performance of the measurement, protection and control systems. Assuming a pre-defined topology, the filter parameters are obtained from the CCVT frequency response of interest. Unlike the techniques reported in the literature, the method applies easily to CCVT of different voltage classes and it does not depend on the operating characteristics of the system, therefore, it is necessary to know the frequency response of the CCVT on the frequency spectrum of interest. The method is validated is through digital simulation using the RTDSTM (Real Time Digital Simulator). The analyzes are based on data obtained from electrical systems in service and on the dynamic performance of the filters by estimating the phasors of voltages and fault location studies. It is shown that the presence of FDR significantly reduces measurement errors caused by CCVT when subjected to transient conditions, therefore, the FDR arises as a simple and low cost alternative to improve the performance and reliability of measurement systems, protection and control.

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