Ces dernières décennies, la recherche et l'application de l'automatique dans les domaines de l'automobile, a contribué fortement dans les aspects sécurité, confort des usagers, économie d'énergie et aide au pilotage.Dans ce contexte, l'objectif principal de cette thèse est le développement d'observateurs par modes de glissement pour l'estimation des états dynamiques, les paramètres dynamiques ainsi que les attributs de la route (dévers de la route), considérés comme des entrées inconnues. Ce type d'observateur est basé sur la théorie des systèmes à structures variables et par l'utilisation d'un modèle représentant de façon réaliste le comportement dynamique du véhicule. A cet effet une proposition de découpage de modèle dynamique complet du véhicule en trois sous-systèmes basé sur le théorie de la passivité a été proposé. Toutes les approches développées ont été validées sur les deux simulateurs de véhicules SCANeRstudio et SIMK106N. / The general framework of the research is the application of the nonlinear control tools (Robust control, Sliding mode Observer, Algebric approach,...) in order to improve the security of vehicle. The estimation of tire road force has become an intensive research area as the interest in information technology in vehicles grows. More and more new safety technologies and approaches are introduced in the automotive environment. Therefore, the problem of traction control for ground vehicles is of enormous importance to automotive industry.We split the dynamic model of vehicle into five subsystems regrouped in three blocks and then show and justify the rationale behind the successful splitting. Thesubsystems and the overall system obey to the passivity property. Robust observer are proposed to estimate the road features.

Neste trabalho são descritos e avaliados diferentes modelos de linhas aéreas de transmissão, considerando a variação dos parâmetros da linha com a frequência. Em geral os modelos apresentados são baseados no uso da matriz de admitâncias nodais, com algumas análises complementares empregando o método das características. São testados casos de circuito-aberto, curto-circuito, linha em carga e manobras com chaves. Os resultados de cálculo são comparados com as respostas simuladas nos programas ATP e PSCAD. Também são apresentadas as formulações para o cálculo de parâmetros da linha de transmissão, considerando o efeito pelicular e a resistividade do solo São avaliadas as respostas no domínio do tempo para diferentes modelos equivalentes de linha de transmissão, obtidos do modelo polo-resíduo com passividade da matriz de admitâncias nodais, sendo empregados: i) transformação do modelo racional para uma representação em espaço de estados, ii) construção de uma rede elétrica equivalente com resistências, indutores e capacitores e iii) representação por meio de um equivalente de Norton. Também é analisado o equivalente de Norton obtido dos modelos polo-resíduo com passividade de uma linha equivalente dobrada nas condições em curto-circuito e circuito-aberto. Foi analisada a solução de redes elétricas no domínio da frequência usando uma formulação nodal e sem a necessidade de ajustes intermediários da matriz de admitâncias nodais. As respostas de tensão e corrente são antitransformadas para o domínio do tempo por meio de diferentes formulações baseadas na transformada inversa de Fourier, levando em conta os métodos que mitigam erros de truncamento e discretização. As seguintes formulações foram avaliadas: i) transformada modificada de Fourier, ii) transformada inversa rápida de Fourier e iii) transformada inversa de Fourier com integração semianalítica. É também apresentado um modelo para linhas de transmissão em paralelo, baseado no domínio modal usando uma matriz de transformação constante, juntamente com a aplicação do método de ajuste Vector Fitting com o objetivo de modelar com precisão o efeito de acoplamento mútuo entre linhas. / In this work different overhead transmission lines models are described and evaluated, considering the frequency dependence of parameters. In general, the models are based on the nodal admittance matrix, with some complementary analysis using the method of characteristics. Cases of open-circuit, short-circuit, line connected to a load and switching maneuvers are tested. The calculation results are compared with the simulated responses obtained with the ATP and PSCAD. The formulations for the transmission line parameters are also presented, taking into account the skin effect and the ground return. The time-domain responses for different transmission line models are evaluated. These models are obtained from the passive pole-residue model of the nodal admittance matrix. The equivalent models are: i) state-space representation, ii) electrical network composed of resistors, inductors and capacitors, iii) the Norton\'s equivalent. In addition, an evaluation is performed for the Norton\'s equivalent obtained from the pole-residue models for the open-circuit and short-circuit conditions of a folded line equivalent. On the other hand, the network is solved completely in frequency-domain using a nodal formulation, without the fitting of the nodal admittance matrix. The voltage and current responses are transformed back to the time-domain by different formulations based on the inverse Fourier transform, taking into account methods to minimize errors by truncation and discretization. The formulations investigated are: i) modified Fourier transform, ii) fast Fourier transform, iii) inverse Fourier transform with semianalytic integration. The model for parallel transmission lines is also evaluated, based on modal domain using a constant transformation matrix and the application of the vector fitting method, with emphasis on accurate representation of mutual coupling effects.

In a Modular High Temperature Gas Reactor (MHGTR), the Pressurized Conduction Cooldown (PCC) event is an accident scenario in which there is a loss of forced convection of the coolant through the system but the pressure boundary remains intact. When the PCC event occurs, natural circulation onsets which results in a flow and temperature reversal, resulting in hot helium flowing into the upper plenum which could imping upon the upper plenum head. The High Temperature Test Facility (HTTF), which is being designed and constructed at Oregon State University, is a scaled thermal test facility of the MHTGR which is being built for both code validation purposes and to examine specific flow phenomena of the gas reactor. This study is being performed to determine how the HTTF simulates the same conditions as the MHTGR under this scenario through the use of scaling parameters and computational fluid dynamics. / Graduation date: 2013

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This thesis introduces a new modeling approach that allows very large power systems to be modeled on a real time electro-magnetic transients (EMT) digital simulator with reduced hardware costs. The key step in achieving this is the development of an improved wide-band multi-port equivalent, which reduces a large power network into a small manageable equivalent model that preserves wideband behaviors. This approach has a foundation method that use a two part equivalent in which the high frequency behavior of the equivalenced network is represented by a terminating frequency dependent network equivalent (FDNE), with the low frequency behavior being modeled using a detailed Transient Stability Analysis (TSA) model that only models the electromechanical behavior. This approach allowed the modelling of medium size electric regions up to hundreds of buses in real time. This thesis extends the equivalent by implementing a reduced order of the detailed electromechanical TSA equivalent mentioned above. Coherency based reduction is used for the electromechanical model of the power network to be equivalenced, and is implemented as a Transient Stability Analysis (TSA) type electromechanical equivalent. A challenge in implementing the FDNE is to ensure that it is a passive network, as otherwise its inclusion could lead to unstable simulation. This thesis also introduces a practical procedure to enforce passivity in the FDNE. The validity of the proposed technique is demonstrated by comparing the approach with detailed electromagnetic simulations of the well-known 39 bus New England system and a modified 39 bus system with an HVDC infeed with coupling between the dc line and an adjacent ac line, in addition to a 108 bus ac system. The power of the method is demonstrated by the real-time simulation of a large system with 2300 busses and 139 generators. It has been shown that this approach has the potential to increase by at least one order of magnitude the size of the network that can be modeled and thus on a real time electro-magnetic transients (EMT) digital simulator with reduced hardware costs.

This thesis introduces a new modeling approach that allows very large power systems to be modeled on a real time electro-magnetic transients (EMT) digital simulator with reduced hardware costs. The key step in achieving this is the development of an improved wide-band multi-port equivalent, which reduces a large power network into a small manageable equivalent model that preserves wideband behaviors. This approach has a foundation method that use a two part equivalent in which the high frequency behavior of the equivalenced network is represented by a terminating frequency dependent network equivalent (FDNE), with the low frequency behavior being modeled using a detailed Transient Stability Analysis (TSA) model that only models the electromechanical behavior. This approach allowed the modelling of medium size electric regions up to hundreds of buses in real time. This thesis extends the equivalent by implementing a reduced order of the detailed electromechanical TSA equivalent mentioned above. Coherency based reduction is used for the electromechanical model of the power network to be equivalenced, and is implemented as a Transient Stability Analysis (TSA) type electromechanical equivalent. A challenge in implementing the FDNE is to ensure that it is a passive network, as otherwise its inclusion could lead to unstable simulation. This thesis also introduces a practical procedure to enforce passivity in the FDNE. The validity of the proposed technique is demonstrated by comparing the approach with detailed electromagnetic simulations of the well-known 39 bus New England system and a modified 39 bus system with an HVDC infeed with coupling between the dc line and an adjacent ac line, in addition to a 108 bus ac system. The power of the method is demonstrated by the real-time simulation of a large system with 2300 busses and 139 generators. It has been shown that this approach has the potential to increase by at least one order of magnitude the size of the network that can be modeled and thus on a real time electro-magnetic transients (EMT) digital simulator with reduced hardware costs.

O objetivo principal desta dissertação é analisar o processo de industrialização da economia brasileira, entre 1930 e 1980, sob uma ótica evolucionária. Ademais, se buscará analisar o catching-up que possibilitou a inserção da economia brasileira no quarto paradigma tecno-econômico, entre 1956-1980. E o subsequente falling-behind dessa economia, que entravou a sua entrada no paradigma tecno-econômico da tecnologia da informação. Como objetivos específicos emerge, em primeiro lugar, a necessidade de se descrever os aspectos tecnológicos, econômicos e institucionais desses dois paradigmas. Em segundo lugar se demonstrará de que maneira o Processo de Substituição de Importações foi fundamental para a inserção da economia brasileira no paradigma da produção em massa. E em terceiro lugar, se demonstrará que o legado institucional dessa mesma estratégia de desenvolvimento veio a ser um obstáculo à inserção da economia brasileira no quinto paradigma tecno-econômico. Destarte, a hipótese assumida é de que a dificuldade enfrentada pelo Brasil para assimilar os fatores-chave derivados da quinta revolução tecnológica advém da precária estrutura institucional construída ao longo da industrialização via substituição de importações. A passividade tecnológica e fragilidade institucional desse modelo de desenvolvimento, que não estabeleceu um nexo micro-macro, foi um obstáculo à endogenização do processo inovativo e impediu que a indústria brasileira ficasse em sintonia com a tecnologia dominante. / The main objective of this dissertation is to analyze the process of industrialization of the Brazilian economy, between 1930 and 1980 under an evolutionary perspective. Moreover, it will try to analyze the catching-up which allowed the insertion of the Brazilian economy in the fourth techno-economic paradigm, from 1956 to 1980. Besides that it will investigate the subsequent falling-behind of this economy, which impeded their entry into the techno-economic paradigm of information technology. The specific objectives emerge, first, the need to describe the technological, economic and institutional features those two paradigms. Secondly it will demonstrate how the Import Substitutive Process was essential for the insertion of the Brazilian economy in the paradigm of mass production. And thirdly, it will demonstrate that the institutional legacy of that development strategy came to be an obstacle to the insertion of the Brazilian economy in the fifth techno-economic paradigm. Thus, the assumption made is that the difficulty faced by Brazil to assimilate the key factors derived from the fifth technological revolution comes from poor institutional structure built along the industrialization through import substitution. Technological passivity and institutional weakness of this model of development, which has not established a micro-macro link, was an obstacle to endogenization of the innovative process and prevented the Brazilian industry to stay in tune with the dominant technology.

O objetivo principal desta dissertação é analisar o processo de industrialização da economia brasileira, entre 1930 e 1980, sob uma ótica evolucionária. Ademais, se buscará analisar o catching-up que possibilitou a inserção da economia brasileira no quarto paradigma tecno-econômico, entre 1956-1980. E o subsequente falling-behind dessa economia, que entravou a sua entrada no paradigma tecno-econômico da tecnologia da informação. Como objetivos específicos emerge, em primeiro lugar, a necessidade de se descrever os aspectos tecnológicos, econômicos e institucionais desses dois paradigmas. Em segundo lugar se demonstrará de que maneira o Processo de Substituição de Importações foi fundamental para a inserção da economia brasileira no paradigma da produção em massa. E em terceiro lugar, se demonstrará que o legado institucional dessa mesma estratégia de desenvolvimento veio a ser um obstáculo à inserção da economia brasileira no quinto paradigma tecno-econômico. Destarte, a hipótese assumida é de que a dificuldade enfrentada pelo Brasil para assimilar os fatores-chave derivados da quinta revolução tecnológica advém da precária estrutura institucional construída ao longo da industrialização via substituição de importações. A passividade tecnológica e fragilidade institucional desse modelo de desenvolvimento, que não estabeleceu um nexo micro-macro, foi um obstáculo à endogenização do processo inovativo e impediu que a indústria brasileira ficasse em sintonia com a tecnologia dominante. / The main objective of this dissertation is to analyze the process of industrialization of the Brazilian economy, between 1930 and 1980 under an evolutionary perspective. Moreover, it will try to analyze the catching-up which allowed the insertion of the Brazilian economy in the fourth techno-economic paradigm, from 1956 to 1980. Besides that it will investigate the subsequent falling-behind of this economy, which impeded their entry into the techno-economic paradigm of information technology. The specific objectives emerge, first, the need to describe the technological, economic and institutional features those two paradigms. Secondly it will demonstrate how the Import Substitutive Process was essential for the insertion of the Brazilian economy in the paradigm of mass production. And thirdly, it will demonstrate that the institutional legacy of that development strategy came to be an obstacle to the insertion of the Brazilian economy in the fifth techno-economic paradigm. Thus, the assumption made is that the difficulty faced by Brazil to assimilate the key factors derived from the fifth technological revolution comes from poor institutional structure built along the industrialization through import substitution. Technological passivity and institutional weakness of this model of development, which has not established a micro-macro link, was an obstacle to endogenization of the innovative process and prevented the Brazilian industry to stay in tune with the dominant technology.

O objetivo principal desta dissertação é analisar o processo de industrialização da economia brasileira, entre 1930 e 1980, sob uma ótica evolucionária. Ademais, se buscará analisar o catching-up que possibilitou a inserção da economia brasileira no quarto paradigma tecno-econômico, entre 1956-1980. E o subsequente falling-behind dessa economia, que entravou a sua entrada no paradigma tecno-econômico da tecnologia da informação. Como objetivos específicos emerge, em primeiro lugar, a necessidade de se descrever os aspectos tecnológicos, econômicos e institucionais desses dois paradigmas. Em segundo lugar se demonstrará de que maneira o Processo de Substituição de Importações foi fundamental para a inserção da economia brasileira no paradigma da produção em massa. E em terceiro lugar, se demonstrará que o legado institucional dessa mesma estratégia de desenvolvimento veio a ser um obstáculo à inserção da economia brasileira no quinto paradigma tecno-econômico. Destarte, a hipótese assumida é de que a dificuldade enfrentada pelo Brasil para assimilar os fatores-chave derivados da quinta revolução tecnológica advém da precária estrutura institucional construída ao longo da industrialização via substituição de importações. A passividade tecnológica e fragilidade institucional desse modelo de desenvolvimento, que não estabeleceu um nexo micro-macro, foi um obstáculo à endogenização do processo inovativo e impediu que a indústria brasileira ficasse em sintonia com a tecnologia dominante. / The main objective of this dissertation is to analyze the process of industrialization of the Brazilian economy, between 1930 and 1980 under an evolutionary perspective. Moreover, it will try to analyze the catching-up which allowed the insertion of the Brazilian economy in the fourth techno-economic paradigm, from 1956 to 1980. Besides that it will investigate the subsequent falling-behind of this economy, which impeded their entry into the techno-economic paradigm of information technology. The specific objectives emerge, first, the need to describe the technological, economic and institutional features those two paradigms. Secondly it will demonstrate how the Import Substitutive Process was essential for the insertion of the Brazilian economy in the paradigm of mass production. And thirdly, it will demonstrate that the institutional legacy of that development strategy came to be an obstacle to the insertion of the Brazilian economy in the fifth techno-economic paradigm. Thus, the assumption made is that the difficulty faced by Brazil to assimilate the key factors derived from the fifth technological revolution comes from poor institutional structure built along the industrialization through import substitution. Technological passivity and institutional weakness of this model of development, which has not established a micro-macro link, was an obstacle to endogenization of the innovative process and prevented the Brazilian industry to stay in tune with the dominant technology.