A crise na biodiversidade tem se agravado como resultado das atividades humanas. Identificar os efeitos ecológicos causados por empreendimentos, como linhas de transmissão de energia elétrica (LTs), é essencial para o planejamento dessas estruturas e para melhor informar seu processo de tomada de decisão. A Avaliação de Impacto Ambiental (AIA) é um importante instrumento para a minimização de impactos na biodiversidade. No entanto, uma das maiores deficiências para a mitigação de impactos está na ausência da antecipação dos mesmos na fase de planejamento das estruturas. Um dos objetivos deste estudo foi listar e descrever os potenciais efeitos ambientais causados pelas LTs, sua natureza e os componentes bióticos afetados. A partir de uma abordagem de revisão sistemática, a síntese dos estudos mostrou que as interações das linhas com a biodiversidade têm sido investigadas em uma grande amplitude de organismos, abordando doze diferentes efeitos no ambiente. No entanto, é notável a ausência de estudos relacionados a grupos funcionais de menor mobilidade e sobre efeitos como a perda de habitat. Além de listar e descrever os efeitos das LTs, este trabalho estruturou um modelo conceitual para auxiliar na definição do escopo das AIAs. Nós acreditamos que o reconhecimento antecipado do espectro de potenciais impactos, além de ser importante para a compreensão das cadeias causais pelas quais as ações de cada empreendimento conduzem efeitos, auxilia na qualificação do processo de licenciamento, direcionando os estudos para impactos prioritários. Como a forma mais efetiva de evitamento de impactos, nós recomendamos fortemente que iniciativas de espacialização dos mesmos sejam desenvolvidas para a futura incorporação no planejamento da expansão da rede de transmissão de energia. / The biodiversity crisis has worsened in the last decades, as a result of human activities. Identifying the ecological effects caused by infrastructure developments, such as electric power transmission lines (TLs), is essential for planning these developments and for better informing the decision-making process. Environmental Impact Assessment (EIA) is an important instrument to ensure the minimization of impacts on biodiversity. However, one of the major shortcomings for mitigation of impacts is the lack of anticipation in the planning phase of these developments. One of the objectives of this study was to list and describe the potential environmental effects caused by TLs, their nature and the affected biotic components. From a systematic review approach, the synthesis of the studies reveal that line interactions with biodiversity have been investigated over a wide range of organisms, addressing twelve different effects on the environment. However, the absence of studies related to functional groups of lower mobility and other effects, such as habitat loss, is notable. In addition to listing and describing the effects of LTs, this work structured a conceptual model to help define the scope of EIAs. We believe that the early recognition of the spectrum of potential impacts, in addition to being important for understanding the causal chains through which the actions of each undertaking have effects, helps in the qualification of the licensing process, directing the studies to priority impacts. As the most effective way of avoiding impacts, we strongly recommend that spatial analysis and investigation should be developed and incorporated in planning the expansion of the power transmission network.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / A geraÃÃo de energia elÃtrica que combina o desenvolvimento humano com menos impactos ambientais e menos poluiÃÃo à um item fundamental no inÃcio deste sÃculo. Assim, a principal motivaÃÃo da caminhada atual à o desenvolvimento de novas topologias de sistemas descentralizados de fornecimento de energia. O objetivo à desenvolver um conversor bidirecional com alto ganho tensÃo, que à projetado para operar em dois modos: boost e buck. A topologia apresentada permite a transferÃncia bidirecional de energia, o que em algumas situaÃÃes, à transferida para o barramento CC, ou para um banco de baterias. O conversor à projetado para um potÃncia de 2 kW. à apresentado o desenvolvimento teÃrico e experimental do projeto para os dois modos de operaÃÃo. A fim de validar a proposta, sÃo apresentados resultados experimentais, para uma potÃncia de 1 kW. Os resultados foram satisfatÃrios e seu rendimento global de 93%. O protÃtipo foi testado em condiÃÃes diferentes que podem ser encontradas no dia-a-dia. / The achievement of energy generation which combines human development with less environment pollution impact is a key item in the premises of this century. Thus the main motivation of the present walk is the development of new topologies for decentralized supply systems. The objective is to develop a bidirectional converter with high voltage gain, which is designed to operate in two modes: step-up (boost) and step down (buck). The presented topology enables to bidirectional energy transfer, which in some situations it is returned to the load DC bus, formed by a back of batteries. The converter is designed for 2 kW linear load power. If is presented theoretical development and experimental designs for the two operation modes. In order to validate the proposal, it is presented experimental results, from 1 kW laboratory prototype are presented as well and 93% overall efficiency. The prototype was tested in different conditions that may be found daily.

Orientador: Elnatan Chagas Ferreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-16T09:48:26Z (GMT). No. of bitstreams: 1 Spengler_AndersonWedderhoff_M.pdf: 5622371 bytes, checksum: dd49f965749d4c55fa19542a3a801d9c (MD5) Previous issue date: 2010 / Resumo: Esta dissertação aborda o projeto de um sistema de caracterização de sensores baseados em fibras ópticas para alta-tensão. O sistema é formado por dois módulos principais, um relacionado com a câmara térmica e outro relativo à alta-tensão. O desenvolvimento do sistema deve-se basicamente às necessidades de personalização e precisão para a caracterização dos sensores e outras aplicações. A câmara climática tem seu projeto eletrônico e mecânico descritos, com ênfase na utilização de módulos termoelétricos, nos controladores proporcional-integral-derivativos utilizados e os parâmetros de sintonia encontrados. Foi feito o estudo da configuração que utiliza dois módulos termoelétricos em série, apontando as vantagens e desvantagens desta configuração. A faixa de temperatura para a câmara obtida é de 0 ºC até 70 ºC, com erro ±0,1 ºC semelhantes às câmaras climáticas comerciais. Há a proposta de um circuito gerador e analisador de ondas arbitrárias de alta-tensão, e ensaios com um sistema semelhante ao proposto para tensões de até 15 kV, para validação do método de eliminação de harmônicas proposto nesta dissertação, obtendo resultados de THD da ordem de 0,04%, valor este limitado pela definição do analisador de sinais / Abstract: This work discusses the project of a characterization system fiber optics based sensors for high-voltage. The system consists of two main modules, one related to the thermal chamber and another on high-voltage part. The system development was mainly due to the needs of customization and precision for the characterization of sensors and other applications. The thermal chamber has its electronic and mechanical design described, with emphasis on the use of thermoelectric modules, the proportional-integral-derivative controllers and their tuning parameters. A study was conducted on the configuration that uses two thermoelectric modules in series, showing the advantages and disadvantages of this configuration. The obtained temperature range for the chamber was 0°C to 70 °C with ± 0.1 °C error, similar to the commercial chambers. There is a proposal for a circuit for arbitrary high voltage wave generator and analyzer, and tests with one system similar to that proposed for voltages up to 15kV, to validate a harmonics eliminator method, obtaining results of THD about 0.04% which is limited by the definition of signal analyzer / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica

Este trabalho tem por objetivo apresentar um novo conceito para a concepÃÃo de conversores para aplicaÃÃes em energias renovÃveis e carregamento de baterias com um nÃmero reduzido de estÃgios de processamento. SÃo desenvolvidas trÃs topologias diferentes de conversores de alto ganho de tensÃo com um Ãnico estÃgio de processamento e capaz de operar tanto com um banco de baterias como com painÃis fotovoltaicos. A operaÃÃo destes conversores permite que as fontes de entradas (painÃis ou baterias) operem de forma natural, independentemente ou complementarmente, compondo um barramento CC e apresentando a comutaÃÃo suave dos interruptores. Por fim, foram desenvolvidos trÃs protÃtipos para uma potÃncia de 500 W que validam o princÃpio de funcionamento dos sistemas propostos apresentando alto rendimento, alto ganho de tensÃo e boa regulaÃÃo do barramento CC em todos os modos de operaÃÃo. / Taking into account the great technological development on renewable energy systems and their applications on power electronics, this work presents a new concept of converters applied to renewable systems and batteries charging with a reduced number of energy processing stages. This work approaches three different high voltage gain converters topologies with only one processing stage, and with bidirectional capability, with batteries, and with photovoltaic panels. The operation of these converters allow that the inputs (PVpanels or batteries), work independently or simultaneously, in order to compose a single DC bus. Also, proposed topologies present natural soft-switching operation. At last, the three prototypes were developed to work with a nominal power of 500W, validating the operation principle of the proposed system, featuring high efficiency, high voltage gain, and good voltage regulation on the DC bus.

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Increased electrical power demands are being experienced on the new generation of aircraft due to an increased reliance on electrical technology of systems such as air conditioning, de-icing systems and electrical flight control actuation. Distribution of power at higher AC and DC voltages is therefore now being seen in modern aircraft to avoid the penalties incurred due to high cable weights. Voltages have increased past the minimum of Paschen's law resulting in a risk that life limiting partial discharge (PD) damage can occur in the insulation systems. This thesis uses a theoretical analysis backed by PD experimental results to investigate the optimal operating voltage of a cabling system. In addition, it proposes a methodology for optimizing the operating voltage level based on an analysis of the power carrying capability of cabling within a fixed and a non-fixed volume system and the derivation of the cable weight as a function of voltage. Furthermore the power carrying capability of a certain round cable system is compared with an insulated flat conductor system as in a printed circuit board (PCB). An initial assessment has been carried out to determine whether more power can be delivered via insulated flat solid conductors as in a PCB, instead of using round cables. The reason why there is a need to investigate this aspect, is because using new PCB technology can offer several advantages over traditional cabling harnesses. The work done has shown that the optimal operating point (e.g. maximum power to weight ratio) for an aircraft power system, does not improve after certain voltage levels. A tradeoff between cable weight and power transfer is required and furthermore the use of DC systems can result in higher power transfers than conventional three phase/400Hz AC systems. The PCB maximum power transfer assessment has also shown that insulated flat conductor systems can offer higher power transfer efficiencies. In addition, experimental AC and DC PD tests on certain unscreened aerospace cables (laid out in different configurations), have shown that the theoretical analysis employed to determine cable safe operating voltages gives conservative results.

Due to the universal considerable population and economic growth rate, demands for energy have risen significantly over the past decade. This means that the integration of renewable energies in the power grid has escalated as well as requests for reactive power compensation, voltage stability, and mitigation of harmonic filters. Capacitor banks are widely used in the modern electrical transmission system in order to improve power quality and efficiency. In other words, this device aims to be involved in harmonic disturbance elimination, improve the power factor (PF), provide voltage control and stability which leads into more sustainable energy systems. Utilizing high voltage components, such as shunt capacitors in the power grid can introduce new challenges. One of these challenges is known as corona discharge. The aim of the presented master thesis is to study and develop corona discharge suppression models on high voltage capacitor banks which is implemented in collaboration with ABB power grids, Sweden. The main concerns are, effective factors on corona emergence, corona inception voltage levels, and corona suppression methods. Also, this study evaluates the verification of existing suppression. Two various approaches were applied and compared. The aim of the first approach is to evaluate corona discharge by electric field calculations on three various capacitor banks with different voltage levels. The simulation was implemented based on Maxwell’s equations and finite element method (FEM) by utilizing COMSOL Multiphysics software. The second approach is based on streamer inception and propagation. The calculation on this method is fulfilled with the help of MATLAB software. The results of both approaches were found reasonably compatible. It is discovered that corona discharge can appear in different voltage levels on capacitor banks based on various factors, such as the geometry of the bank. Consequently, the suppression method may vary case by case and different proposals were suggested in order to optimize the corona suppression rings. / På grund av den allmänna betydande befolknings- och ekonomiska tillväxttakten har kraven på energi ökat markant under det senaste decenniet. Detta innebär att integrationen av förnybara energier i elnätet har eskalerat samt begäran om reaktiv effektkompensering, spänningsstabilitet och mildring av harmoniska filter. kondensatorbatterier används ofta i det moderna elektriska transmissionssystemet för att förbättra strömkvaliteten och effektiviteten. Med andra ord syftar denna enhet till att vara involverad i eliminering av harmonisk störning, förbättra effektfaktorn (PF), tillhandahålla spänningskontroll och stabilitet som leder till mer hållbara energisystem. Att använda högspänningskomponenter, som shuntkondensatorer i elnätet, kan skapa nya utmaningar. En av dessa utmaningar kallas korona-urladdning. Syftet med den presenterade masteruppsatsen är att studera och utveckla korona-urladdningsmodeller på högspännings-kondensatorbatterier som implementeras i samarbete med ABB Power Grids, Sverige. De viktigaste problemen är effektiva faktorer för korona uppkomst, spänningsnivåer korona och metoder för att underlätta korona. Dessutom utvärderar denna studie verifieringen av befintliga undertryckningsmetoder. Två olika tillvägagångssätt tillämpades och jämfördes. Syftet med det första tillvägagångssättet är att utvärdera korona-urladdning genom elektriska fältberäkningar på tre olika kondensatorbatterier med olika spänningsnivåer. Simuleringen implementerades baserat på Maxwells ekvationer och finita elementmetoden (FEM) genom att använda COMSOL Multiphysics programvara. Det andra tillvägagångssättet är baserat på strömningslinjernas början och utbredning. Beräkningen av denna metod genomförs med hjälp av MATLAB-programvaran. Resultaten från båda metoderna tycktes vara rimligt kompatibla. Det upptäcks att korona-urladdning kan förekomma i olika spänningsnivåer på kondensatorbatterier baserat på olika faktorer, till exempel batteriets geometri. Följaktligen kan undertryckningsmetoden variera från fall till fall och olika förslag föreslogs för att optimera koronaundertryckningsringarna.

L'autonomie est, à l'heure actuelle, un des points les plus bloquants des véhicules électriques. Une optimisation du rendement de la chaîne de conversion est donc un objectif primordial. La thèse s'inscrit donc dans un contexte d'efficacité énergétique et d'intégration en électronique de puissance. Il s'agira d'améliorer les rendements de conversion et la puissance massique à la fois par le choix de technologies adaptées et par la conception de structures de conversion optimisées. Dans un premier temps, nous présentons l’impact de l’évolution de la tension de batterie HT sur le choix des technologies de composants de puissance. Différentes architectures de conversion sont également présentées et l’accent est mis sur un convertisseur en particulier : L’onduleur. Puis, nous comparons les relevés expérimentaux à ceux qui peuvent sont fournis par des fabricants pour certains composants et dans certaines conditions de fonctionnement. Ces essais permettent également d’enrichir les données des fabricants. Enfin, nous comparerons l’impact de la montée en tension des batteries HT sur les performances de différentes structures d’onduleurs (2 et 3 niveaux), pour différentes technologies de composants semi-conducteurs de puissance et pour différents points de fonctionnement de la machine associée. / Currently, autonomy of electric vehicles is one of the most blocking points for developing such mean of transport. An optimization of the efficiency of the power train is thus a primordial objective. The thesis is part of a context of energy efficiency and integration in power electronics. This will improve conversion efficiencies and mass power both by the choice of appropriate technologies and design optimized conversion structures. First, we present the impact of the evolution of the HT battery voltage on the choice of power component technologies. Different conversion architectures are also presented and the focus is on a particular converter: The inverter. Then, we compare the experimental records to those that can be supplied by manufacturers for certain components and under certain operating conditions. These tests also make it possible to enrich the data of the manufacturers. Finally, we will compare the impact of the voltage rise of the HT batteries on the performances of various inverter structures (2 and 3 levels), for different technologies of semiconductor power components and for different operating points of the machine associated.

Der vorliegende Posterbeitrag beschäftigt sich mit der Entwicklung angepasster Entwicklungsmethoden für nachhaltig aufgebaute Hochvolt-Speicher. Dazu wird zunächst analysiert, welche technischen Kriterien bei der Produktgestaltung vor dem Hintergrund der Wiederverwendbarkeit einzelner Komponenten besondere Berücksichtigung finden müssen. Unter Zuhilfenahme der Recycling-Kaskade aus der VDI 2243 wird die Entscheidungsfindung im Konstruktionsprozess methodisch ergänzt sowie die notwendigen Betrachtungen, die das Vorgehen objektiv bewerten, vorgestellt. Die Notwendigkeit eines zeitlichen und kostenseitigen Montage-Demontage-Abgleichs ist für die Erreichung der Ziele unabdingbar, da im Rahmen des Entwicklungsprozesses keine Suboptima entstehen sollen. Im Anschluss wird an einem Beispiel aus dem direkten Forschungsumfeld der Autoren, ein 48V-Submodul eines HV-Speichers, das Vorgehen und die Rückschlüsse für die Entwicklung und Konstruktion veranschaulicht. Abschließend werden die gewonnenen Erkenntnisse für die Konstruktionssystematik von HV-Speichern verallgemeinert und dienen der Beantwortung folgender Fragen: Welche Größen beeinflussen unmittelbar die Instandsetzung- und damit die Wieder- bzw. Weiterverwendbarkeit? — Welche Aspekte müssen zur Sicherstellung der Nachhaltigkeit (z.B. Langlebigkeit und Zweitnutzung der Module etc.) zwangsweise berücksichtig werden? — Wie kann sichergestellt werden, dass mit nicht formstabilen und thermisch komplexen Einzelteilen (Zellen) eine sichere Demontagefähigkeit gewährleitet ist? — Welche Detektierungsverfahren und –methoden sind notwendig?