Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Swaminatham, Madhavan.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1995. / Vita. Abstract. Includes bibliographical references (leaves 202-207). Also available via the Internet.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 60-61). Also available via the Internet.

Thesis (M.S.)--Ohio University, November, 1993. / Title from PDF t.p.

Thesis (M.S.)--University of Wisconsin--Madison, 1967. / Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 115-121). Also available via the Internet.

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 80-84). Also available on the World Wide Web.

by Shankar Sastry. / "September 1982." / Bibliography: p. 37-38. / Air Force Office of Scientific Research grant AFOSR-82-0258

This thesis is concerned with the synthesis of passive networks, motivated by the recent invention of a new mechanical component, the inerter, which establishes a direct analogy between mechanical and electrical networks. We investigate the minimum numbers of inductors, capacitors and resistors required to synthesise a given impedance, with a particular focus on transformerless network synthesis. The conclusions of this thesis are relevant to the design of compact and cost-effective mechanical and electrical networks for a broad range of applications. In Part 1, we unify the Laplace-domain and phasor approach to the analysis of transformerless networks, using the framework of the behavioural approach. We show that the autonomous part of any driving-point trajectory of a transformerless network decays to zero as time passes. We then consider the trajectories of a transformerless network, which describe the permissible currents and voltages in the elements and at the driving-point terminals. We show that the autonomous part of any trajectory of a transformerless network is bounded into the future, but need not decay to zero. We then show that the value of the network's impedance at a particular point in the closed right half plane can be determined by finding a special type of network trajectory. In Part 2, we establish lower bounds on the numbers of inductors and capacitors required to realise a given impedance. These lower bounds are expressed in terms of the extended Cauchy index for the impedance, a property defined in that part. Explicit algebraic conditions are also stated in terms of a Sylvester and a Bezoutian matrix. The lower bounds are generalised to multi-port networks. Also, a connection is established with continued fraction expansions, with implications for network synthesis. In Part 3, we first present four procedures for the realisation of a general impedance with a transformerless network. These include two known procedures, the Bott-Duffin procedure and the Reza-Pantell-Fialkow-Gerst simplification, and two new procedures. We then show that the networks produced by the Bott-Duffin procedure, and one of our new alternatives, contain the least possible number of reactive elements (inductors and capacitors) and resistors, for the realisation of a certain type of impedance (called a biquadratic minimum function), among all series-parallel networks. Moreover, we show that these procedures produce the only series-parallel networks which contain exactly six reactive elements and two resistors and realise a biquadratic minimum function. We further show that the networks produced by the Reza-Pantell-Fialkow-Gerst simplification, and the second of our new alternatives, contain the least possible number of reactive elements and resistors for the realisation of almost all biquadratic minimum functions among the class of transformerless networks. We group the networks obtained by these two procedures into two quartets, and we show that these are the only quartets of transformerless networks which contain exactly five reactive elements and two resistors and realise all of the biquadratic minimum functions. Finally, we investigate the minimum number of reactive elements required to realise certain impedances, of greater complexity than the biquadratic minimum function, with series-parallel networks.

Made available in DSpace on 2016-03-07T19:21:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-11-05. Added 1 bitstream(s) on 2016-03-07T19:24:55Z : No. of bitstreams: 1 000858966.pdf: 2028080 bytes, checksum: dac7a5c9d241c31e2066c270e8e6f473 (MD5) / O presente trabalho aborda o assunto da atribuição de responsabilidades em circuitos elétricos monofásicos com características de baixa tensão (baixo nível de curto circuito). Nesse cenário, o avanço das cargas eletrônicas e das fontes chaveadas propiciou um ambiente na qual tensão e corrente carregam alto conteúdo harmônico desfavorecendo, de certa forma, a Qualidade da Energia Elétrica (QEE). Nesse contexto, o objetivo do trabalho é estudar o comportamento de cargas lineares e não lineares e traçar conclusões a respeito de atribuição de responsabilidades. Para tanto, utilizouse a Teoria da Potência Conservativa (CPT) (do inglês, Conservation Power Theory) que é um modelo matemático para análise de circuitos elétricos sob condições senoidais e não seniodais. Além disso, a CPT permite expandir a análise do problema proposto através de uma Metodologia de Atribuição de Responsabilidades que leva em consideração um circuito equivalente com as informações da impedância de linha (equivalente Thévenin da rede visto pelo PAC) e dos parâmetros equivalentes da carga, mostrando um diferencial frente às metodologias estudadas. Para tanto, um circuito elétrico composto por diferentes cargas lineares e não lineares foi proposto e se pode estudar e discutir o compartilhamento de responsabilidades, buscando respostas acerca das quais parcelas de potência devem ser apontadas às cargas geradoras dos distúrbios harmônicos. A caracterização de cargas e estimação de impedância de linha apresentam resultados bastante satisfatórios. Assim, a metodologia de atribuição de responsabilidades sugere que a potência ativa fundamental deveria ser de responsabilidade das cargas, uma vez que ela representa de fato o fluxo de potência da fonte de alimentação para a carga. Além disso, o trabalho mostrou a fragilidade da PRODIST frente à norma IEEE em relação aos níveis de distorção harmônica de tensão no PAC... / This work, aims to the study of the accountability problem focused on single-phase circuits with low voltage characteristics (low level of short circuit). In this scenario, the advancement of electronic loads and switchin devices have promoted and environment in which voltages and currents present high harmonic content, reducing the electrical power quality. In this context, the objective of this work is to study the behavior of linear and nonlinear loads and draw conclusions on accountability in electrical grids, i.e., responsibility in the harmonic content generation. For this purpose, it was applied the Conservative Power Theory (CPT) which is a mathematical tool for electrical circuits analysis on both sinusoidal and nonsinusoidal conditions. Furthermore, the CPT allows the application of a Accontability Methodology that takes into account information of the line impedance (equivalent Thévenin viewed by point of common coupling) and the equivalent parameters of the load. These two considerations represent a differential in relation to the studied methodologies. So, an electrical circuit containing linear and non-linear loads was proposed, and the Accountability Methodology was studied and discussed, seeking answers about the power portions that should be accontable to the harmonic loads. The load characterization and the impedance estimation presented satisfactory results. Then, the Accontability Methodology proposes that the fundamental active power should be accontable to the loads, since it represents the power portion that really flows the power source to the load. In addition, the work showed the fragility of PRODIST in relation to the IEEE standard concerning the harmonic voltage distortion established limits at the point of common coupling