Orientador: Dionízio Paschoareli Júnior / Banca: Luis Carlos Origa de Oliveira / Banca: Walmir de Freitas Filho / Resumo: O setor de distribuição de energia elétrica vem apresentando constantes mudanças para se adaptar à necessidade de atendimento das crescentes demandas com recursos financeiros e energéticos cada vez mais escassos. Concessionárias têm buscado eficiência operacional em seus processos através de tecnologias que visam atender a um consumidor cada vez mais exigente por qualidade na utilização da energia elétrica. Neste cenário, a utilização de equipamentos que flexibilizem a operação das redes de distribuição apresentam-se como alternativas menos onerosas quando comparadas com a realização de grandes investimentos na expansão. O uso de equipamentos de flexibilização nas redes de distribuição possui peculiaridade específicas que prevê adaptações de natureza elétrica e física no sistema. O compensador série controlado a tiristores apresenta-se como uma alternativa a ser considerada para aplicação em redes de até 36kV. Aspectos de robustez face a necessidade de flexibilização são discutidos de modo a analisar sua postergação de investimentos visando mitigar ou diminuir o impacto de grandes alterações em redes de distribuição. Tais adaptações são comparadas com a sua viabilidade econômica, a partir da adequação da relação custo-benefício. Os resultados das análises apontam para uma tendência favorável à utilização do compensador série controlado a tiristores na rede de distribuição (D-TCSC), quando considerados os valores de implantação, tempo de execução física, instituição de condições mais favoráveis para realização de manobras e retorno mais rápido na imobilização de cálculos de tarifas e retorno do capital investido / Abstract: The electrical distribution system has presented constant changes to adapt to the growth in power demand with reducing financial and energetic resources availability. Utilities are looking for improvement in operating conditions using new technologies to attend to high power quality by the most demanding consumer. The use of equipment to improve the flexibility of distribution systems is an alternative which postpone large investments in system expansion. The thyristor-controlled series compensator is an attractive option for networks up to 36 kV. In this work, flexible solutions are discussed to postpone investments. Economical viability of a series controlled compensator in a distribution system is presented. The results take in account the initial cost, time of implementation, return on invested capital, among others / Mestre

Orientador: Antonio Roberto Balbo / Coorientador: Ricardo Bento Nogueira Mori Pinheiro / Banca: Marcelo Suetake / Banca: Sonia Cristina Poltroniere Silva / Resumo: Neste trabalho, são apresentadas técnicas de otimização multiobjetivo, de Programação por Metas Ponderadas e de Restrições Canalizadas Progressivas, consideradas para propor uma técnica mista denominada de Programação por Metas Ponderadas com Restrições Canalizadas Progressivas (PMPRCP), as quais são aplicadas ao Problema Multiobjetivo de Despacho Econômico e Ambiental, com o efeito Ponto de Carregamento de Válvula (PMDEA-PV), próprios da área de geração de ebnergia. A abordagem relacionada a programação por metas ponderadas visa a minimização das variáveis de desvio pré-definidas, com o intuito de determinar soluções de compromisso para o PMDEA-PV, considerando metas pré-estabelecidas relativas à função de custos, do problema de despacho econômico e à função de emissão de poluentes, do problema de despacho ambiental. O intuito do uso da técnica de PMPRCP é determinar a curva de soluções não dominadas para o PMDEA-PV, denominada de soluções Pareto-Eficientes. Os subproblemas mono-objetivos obtidos pelo uso da programação por metas ponderadas e da PMPRCP para a formulação do PMDEA-PV são resolvidos pelo método Primal-Dual Previsor-Corretor de pontos interiores. Ainda neste tabalho, o PMDEA-PV em sua forma canônica é resolvido pelo Algoritmo genético de Ordenação Não-Dominada II (conhecido na literatura por NSGA-II) com o intuito de comparação de resultados para a validação da técnica de PMPRCP apresentada, considerando que o NSGA-II é utilizado no ramo de otimização multiobjet... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work are presented multiobjective optimization techniques, Weighted Goal Programming and Progressive Bounded Constraints, considered to propose a mixed technique called Weighted Goal Programming with Progressive Channeling Constraints (PMPRCP), which are applied to the Economic and Environmental Dispatch Multiobjective Problem with the effect Valve loading point (PMDEA-PV), own of the area of energy generation. The approach related to Weighted Goal Programming aims to minimizing the predefined deviation variables, aiming to determine compromise solutions for the PMDEA-PV, considering pre-established goals related to the cost function related to the problem of economic dispatch and the emission of pollutants related to the problem of environmental dispatch. The purpose of the PMPRCP technique is to determine the curve of non-dominated solutions for PMDEA-PV, called Pareto-Efficient solutions. The mono-objective subproblems obtained from the use of weighted goal programming and the PMPRCP for PMDEA-PV formulation are solved by the Primal-Dual Predictor-Corrector of interior points method. Still in this work, the PMDEA-PV in its canonical form is solved too by a Non-Dominated Sorting Genetic Algorithm II (known in the literature by NSGA-II) with the purpose of comparing results for the validation of the PMPRCP technique presented, considering that NSGA-II is used in the field of multiobjective optimization to determine the curve of non-dominated solutions to multiobjecti... (Complete abstract click electronic access below) / Mestre

The Internet of Things (IoT) is now permeating our daily lives, providing critical data for every decision. IoT architecture consists of multiple layers with unique functions and independent components. Each layer of IoT architecture requires different power sources and power delivery schemes. Therefore, different types of power management architectures are required for individual IoT components. Fortunately, advances in metal oxide semiconductor (MOS) technology have made it possible to implement a variety of high-performance power management architectures. These power management architectures should not only create the power rails required for IoT components but also serve additional functions depending on the application. The power management architecture of IoT devices needs to support sub-mW- or mW-scale power consumption. In addition, the power management architecture should be either fully integrated on a chip or miniaturized with few passive components to minimize the size of IoT devices. Building-scale data centers, on the other hand, need various power conversion stages. In this scenario, power conversion from an intermediate DC bus to many point of loads (PoL) requires a high conversion ratio DC-DC converter. Because each PoL draws enormous amounts of power, the power management architecture should withstand high currents and include protection circuitry to prevent damage. This thesis presents research on the design of power management architectures required by IoT devices and data centers. Chapter 2 presents the design and circuit techniques of power management architectures for IoT devices. Chapter 2 outlines a new methodology for co-designing an integrated switched-capacitor (SC) DC-DC converter and a load circuit in ultra-low-power IoT devices. This methodology enables the implementation of an area-efficient fully integrated IoT system-on-chip (SoC) while maintaining high power conversion efficiency (PCE). Chapter 3 presents a 10-output ultra-low-power single-inductor-multiple-output (SIMO) DC-DC buck converter with integrated output capacitors for sub-mW IoT SoCs. Featuring a continuous comparator-based output switch controller and a digital pulse-width modulation (PWM) controller for ultra-low feedback latency, this SIMO converter produces ten independent output voltages with high PCE. Lastly, in Chapter 4, an integrated programmable gate timing control and gate driver chip for an active-clamp forward converter (ACFC) Power Block for data center applications is developed. While the ACFC Power Block converts 12-48 V intermediate DC bus voltage to a digital PoL voltage, the gate timing control and driver chip can optimize PCE and reduce the system form factor.

The recent development of Integrated Power Systems (IPS) for shipboard application has opened the horizon to introduce new technologies that address the increasing power demand along with the associated performance specifications. Similarly, the Shipboard Power System (SPS) features system components with multiple dynamic characteristics and require stringent regulations, leveraging a challenge for an efficient system level management. The shipboard power management needs to support the survivability, reliability, autonomy, and economy as the key features for design consideration. To address these multiple issues for an increasing system load and to embrace future technologies, an autonomic power management framework is required to maintain the system level objectives. To address the lack of the efficient management scheme, a generic model-based holistic power management framework is developed for naval SPS applications. The relationship between the system parameters are introduced in the form of models to be used by the model-based predictive controller for achieving the various power management goals. An intelligent diagnostic support system is developed to support the decision making capabilities of the main framework. Naïve Bayes’ theorem is used to classify the status of SPS to help dispatch the appropriate controls. A voltage control module is developed and implemented on a real-time test bed to verify the computation time. Variants of the limited look-ahead controls (LLC) are used throughout the dissertation to support the management framework design. Additionally, the ARIMA prediction is embedded in the approach to forecast the environmental variables in the system design. The developed generic framework binds the multiple functionalities in the form of overall system modules. Finally, the dissertation develops the distributed controller using the Interaction Balance Principle to solve the interconnected subsystem optimization problem. The LLC approach is used at the local level, and the conjugate gradient method coordinates all the lower level controllers to achieve the overall optimal solution. This novel approach provides better computing performance, more flexibility in design, and improved fault handling. The case-study demonstrates the applicability of the method and compares with the centralized approach. In addition, several measures to characterize the performance of the distributed controls approach are studied.

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