Tesis sobre el tema "Transmission line model"
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KLAUSNER, JEREMIAS CORAL. "TRANSMISSION LINE MODEL". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1992. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=8740@1.
Texto completoEste trabalho apresenta uma metodologia para simulação de linhas de transmissão, geradores, interconexões e cargas por modelos baseados em filtragem digital. Estes modelos usam de maneira intensiva o conceito de redes digitais equivalentes, para resolver problemas aliados à responsabilidade dos filtros digitais em redes onde haja interconexão de elementos, desde simples cargas a subredes. O resultado deste trabalho é um sistema que representa de maneira quase que integral o espectro do sinal discretizado, em contraposição aos métodos tradicionalmente encontrados na simulação de sistemas deste tipo por computador digital. Por outro lado o processo é facilmente implementado por processadores digitais de sinal (DSPs), resultado em simulações em tempo rela comparáveis a simulações off-line por aplicativos
This thesis introduces a metodology for the simulation of transmission lines, power generators, interconnnections and loads, base don digital filtering models. These models make intensive use of digital equivalent network concepts in order to solve the computability problem of the digital filter. The result of this work is a system that represents the discrete-time signal on a bandwsiths covering up to the Nyquist frequency, in contraposition with traditional methods of computer simulation. The structure is easily implemented with Digital signal Processors (DSPs), resulting in real time simulations that compare to off-line circuit simulators in precision.
DOMINGUES, LUIS ADRIANO DE MELO CABRAL. "MODEL FOR TRANSMISSION LINE CONDUCTORS TEMPERATURE FORECASTING". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2748@1.
Texto completoAs linhas de transmissão têm um papel fundamental no funcionamento do sistema elétrico, efetuando a ligação entre as usinas geradoras e os centros de carga. Quando o sistema de transmissão atinge sua capacidade limite de transferência de potência torna-se necessário expandir o sistema, quer construindo novas linhas quer aumentando a capacidade das existentes. Entre os fatores que limitam a capacidade de transporte de uma linha destaca-se a sua temperatura limite de operação, estabelecida por questões econômicas e de segurança. Pela sua extensão geográfica, a construção de uma linha de transmissão envolve tanto um custo quanto um impacto ambiental elevados. Por estes motivos a recapacitação de linhas existentes, no sentido de aumentar sua capacidade de transporte, tornou-se um assunto prioritário e uma opção estratégica para expansão do sistema elétrico. Neste trabalho analisa-se o problema da temperatura de operação dos condutores de linhas aéreas de transmissão. Descreve-se a metodologia atualmente utilizada para definir o limite operativo das linhas, destacando-se a possibilidade de aumentar sua capacidade limite pelo conhecimento mais preciso da temperatura de operação dos seus condutores.Descreve-se o desenvolvimento de uma série de dois modelos para previsão da temperatura de operação de condutores, um modelo completo, baseado em previsões das diversas variáveis meteorológicas e um modelo direto de previsão que utiliza as séries de valores de temperatura. No desenvolvimento dos modelos de previsão foram utilizados modelos estocásticos, lineares, de amortecimento exponencial e Box-Jenkins e técnicas de Redes Neurais Artificiais. Apresenta-se uma série de testes de validação, que mostram um desempenho muito bom dos métodos de previsão, e ilustra-se as possibilidades de aplicação dos modelos desenvolvidos.
Transmission lines have a fundamental role in the electric system performance,connecting power sources to load centers. When the transmission system attains it`s transmission capability limit, the system must be expanded, either constructing new lines, or upgrading existing ones. Among the factors that can limit a transmission line transfer capability is the operating temperature limit, established for both economic and safety reasons. Due to its geographic extension the construction of a transmission line involves a big economic as well as environmental cost. For this reasons the upgrade of existing lines, in the sense of increasing it`s transmission capability, has become a priority to electric utilities and a main option for system expansion. In this work the problem of transmission line conductors` operational temperature is analised and the methodology presently used to establish it`s operational limit is described. Two models to forecast transmission line conductors` temperature are developped:a complete model which uses forecasts of the relevant metheorological variables,and a direct model using univariate methods on temperature series. In the development of forecasting models, linear stochastic methods such as exponential smoothing and Box-Jenkins, as well as Artificial Neural Networks techniques were used.Finally model validation is presented, showing very good performance of the proposed forecasting models, and some potential applications are suggested.
Zhang, Jiefu. "Characterization of carbon nanostructures based on transmission line model". Thesis, Queen Mary, University of London, 2014. http://qmro.qmul.ac.uk/xmlui/handle/123456789/9102.
Texto completoJohn, Lester Ryan. "An inverse transmission line model of the lower limb arterial system". Doctoral thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/3254.
Texto completoGao, Youxin. "Interconnect optimization in deep sub-micron design under the transmission line model". Digital version:, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p9992795.
Texto completoBeeks, Kyle A. "Arterial blood pressure estimation using ultrasound technology and transmission line arterial model". Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/121663.
Texto completoThesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2019
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 67-69).
This thesis describes the application of a transmission line model to arterial measurements in order to derive useful cardiovascular parameters. Non-invasive ultrasound techniques are used to make these measurements, which has several benefits over invasive methods such as arterial catheterization. However, invasive methods are seen as the "gold standard" measurements and therefore the most accurate. Having accurate measurements that can be done non-invasively would be very desirable for cardiologists to determine their patients' risk of developing cardiovascular disease. This work details how to obtain the blood flow and pulse pressure waveforms using ultrasound transducers. Two transducers, one for imaging and one for Doppler, can be used together to derive these waveforms from distension and blood flow velocity measurements. Unfortunately, the only blood pressure waveform that can be obtained is the pulse pressure, which does not contain diastolic information. By decomposing the backward and forward pulse and flow waves and using the transmission line model, the diastolic pressure can be determined and the complete arterial blood pressure waveform can be obtained.
by Kyle A. Beeks.
M. Eng.
M.Eng. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science
Hoxha, Neriton. "Ultra-fast line protection relay algorithm based on a Gamma model of line". Doctoral thesis, Universite Libre de Bruxelles, 2020. https://dipot.ulb.ac.be/dspace/bitstream/2013/313348/6/contratNH.pdf.
Texto completoDoctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
Uzelac, Lawrence Stevan. "A Multiple Coupled Microstrip Transmission Line Model for High-Speed VLSI Interconnect Simulation". PDXScholar, 1991. https://pdxscholar.library.pdx.edu/open_access_etds/4526.
Texto completoTavighi, Arash. "A frequency-dependent multiconductor transmission line model with collocated voltage and current propagation". Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/60791.
Texto completoApplied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
Beyers, Ryno Dawid. "Circuit model design of conical transmission line power combiners and isolation of reactive combiners". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96976.
Texto completoENGLISH ABSTRACT: This dissertation presents a circuit-based design technique that leads to benefits in terms of the physical size, manufacturability, and exibility in the design of N-way conical line power combiners. An equivalent circuit model for the peripheral input ports of conical line power combiners is extracted, as well as empirical equations that allow the circuit element values to be calculated directly from the physical dimensions of the combiner, and vice versa. This allows for rapid optimization of various dimensions of the combiner at a significantly reduced computational cost compared to full-wave simulations. A design procedure is presented and a conical combiner designed with a measured reflection coefficient of better than -18 dB over a 46 % bandwidth around 10 GHz. The designed prototype is much smaller compared to previous designs while exhibiting similar performance. Design procedures for single-section and multi-section impedance tapered conical to coaxial line transitions are also presented, which can be used to simplify the design of conical combiners and reduce the manufacturing effort. Two combiners are designed, one with a single-section and one with a multi-section transition, and output port reflection coefficients of -23 dB and -17 dB over bandwidths of 20 % and 43 % around 10 GHz are measured, respectively. This dissertation additionally presents a method that can be used in general to improve the input port isolation of N-way power combiners without affecting their reciprocity. A simple S-parameter proof is presented, followed by a derivation of equations that can be used to estimate the worst-case performance. Some design examples are presented, showing that terminations can be used for isolation loads. A prototype based on microstrip transmission lines is manufactured and a much improved input port reflection and isolation performance of -15 dB and 20 dB is measured, respectively, compared to a simulated input port reflection coefficient of -2:5 dB and isolation of 2:5 dB before the method was applied. ii
AFRIKAANSE OPSOMMING: Hierdie proefskrif stel 'n stroombaangebaseerde ontwerpsmetode voor wat lei tot voordele in terme van die fisiese grootte, vervaardigbaarheid, en vryheid in die ontwerp van koniese lyn kombineerders. 'n Ekwivalente stroombaanmodel vir die voerpoorte word onttrek, asook empiriese vergelykings wat gebruik kan word om die stroombaanelement waardes vanaf die afmetings van die kombineerder te bepaal. Dit laat die ontwerper toe om verskeie afmetings van die kombineerder te optimeer teen 'n beduidende laer koste in vergelyking met volgolf simulasies. 'n Ontwerpsprosedure word voorgestel en gebruik om 'n koniese kombineerder te ontwerp en 'n weerkaatskoëffisient van beter as -18 dB met 'n bandwydte van 46 % om 10 GHz word gemeet. Die prototipe is aansienlik kleiner as vorige ontwerpe, maar toon soortgelyke werkverrigting. Ontwerpsprosedures vir enkel en veelvoudige deel koniese na koaksiale lyn oorgange word ook voorgestel, wat gebruik kan word om die ontwerp en vervaardiging van koniese kombineerders te vereenvoudig. Twee kombineerders word ontwerp, een met 'n enkel deel oorgang en een met veelvoudige dele, en onderskeidelike uittree weerkaatskoëffisiente van -23 dB en -17 dB oor bandwydtes van 20 % en 43 % word gemeet. Hierdie proefskrif stel ook 'n metode voor wat gebruik kan word om die intree poort isolasie van N-rigting kombineerders in die algemeen te verbeter, sonder om die wederkerigheid daarvan te beïnvloed. 'n Bewys van die metode word gelewer, gevolg deur 'n afleiding van vergelykings wat gebruik kan word om die slegste-geval werkverrigting af te skat. Verskillende voorbeelde van kombineerders word getoon waarop die metode toegepas is, en wys dat terminasies gebruik kan word vir die isolasie laste. 'n Prototipe gebaseer op mikrostrook transmissielyne word vervaardig en 'n verbeterde intreepoort weerkaatskoëffisient en isolasie van onderskeidelik -15 dB en 20 dB word gemeet, in vergelyking met 'n weerkaatskoëffisient van -2:5 dB en isolasie van 2:5 dB voordat die metode toegepas is.
De, Lauretis Maria. "Transmission line theory for cable modeling: a delay-rational model based on Green's functions". Licentiate thesis, Luleå tekniska universitet, EISLAB, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26517.
Texto completoGodkänd; 2016; 20160318 (mardel); Nedanstående person kommer att hålla licentiatseminarium för avläggande av teknologie licentiatexamen. Namn: Maria De Lauretis Ämne: Industriell Elektronik/Industrial Electronics Uppsats: Transmission Line Theory for Cable Modeling: A delay-rational model based on Green’s functions Examinator: Professor Jonas Ekman, Institutionen för system- och rymdteknik, Avdelning: EISLAB, Luleå tekniska universitet. Diskutant: Professor Sven Nordebo, Institutionen för fysik och elektroteknik, Linnéuniversitetet, Växjö. Tid: Tisdag 3 maj, 2016 kl 10.30 Plats: A1547, Luleå tekniska universitet
Frekvensomriktares funktion i beredskapskritiska system
Torrez, Caballero Pablo. "Inclusão do efeito da frequência no modelo de Bergeron : representação de linhas de transmissão curtas e longas considerando transitórios eletromagnéticos resultantes de operações de manobras e de descargas atmosféricas /". Ilha Solteira, 2018. http://hdl.handle.net/11449/180446.
Texto completoResumo: O objetivo deste projeto é desenvolver um modelo de linha de transmissão que leva em conta as principais características exigidas de um modelo deste componente do sistema elétrico, ou seja, ser desenvolvido diretamente no domínio do tempo, considerar que os parâmetros da linha são distribuídos ao longo de seu comprimento e levar em conta que os parâmetros longitudinais variam em função da frequência. O modelo proposto é baseado no modelo de Bergeron, que é um modelo de linha de transmissão desenvolvido diretamente no domínio do tempo e que leva em conta que os parâmetros de uma linha de transmissão são distribuídos ao longo de seu comprimento. No modelo proposto será levado em consideração que, devido aos efeitos solo e pelicular, os parâmetros longitudinais da linha (resistência longitudinal e indutância longitudinal) são variáveis em relação à frequência. Estes parâmetros serão aproximados por funções racionais e inseridos no modelo de Bergeron. O modelo desenvolvido será utilizado para representar linhas curtas e longas em simulações de transitórios eletromagnéticos resultantes de operações de manobras e de incidências de descargas atmosféricas. Por ser desenvolvido diretamente no domínio do tempo, o modelo proposto pode ser facilmente inserido em aplicativos do tipo ATP (Alternative Transients Program) e será uma ferramenta útil em simulações e análises de transitórios eletromagnéticos em sistemas de energia elétrica.
Abstract: The main objective of our project is to develop a transmission line model that takes into account the main characteristics demanded by a model of this electrical system component, i.e., be developed directly in the time-domain, consider the distributed nature of the line parameters and take into account the frequency dependence of the longitudinal parameters. The proposed model is based on the Bergeron model, which is a transmission line model directly developed in the time domain that takes into account that the transmission line parameters are distributed along its length. In the proposed model it will be taken into account that, due to earth-return effect and skin impedance, the longitudinal parameters (longitudinal resistance and longitudinal inductance) vary in relation to the frequency. These parameters will be approximated by rational functions and will be added to the Bergeron model. The developed model will be used to represent short and long transmission lines in simulations resulting from switching operations and lightning strikes. Because of the model being directly developed in the time-domain, the proposed model can be easily implemented in programs ATP-like (Alternative Transients Program) and will be a useful tool in power system transient analysis.
Doutor
Siegel, Thomas A. "Magnetic fields of an underground coaxial cable caused by return currents in the earth". Ohio : Ohio University, 1989. http://www.ohiolink.edu/etd/view.cgi?ohiou1182517321.
Texto completoMazloom, Ziya. "Multi-conductor transmission line model for electrified railways: A method for including responses of lumped devices". Doctoral thesis, KTH, Elektroteknisk teori och konstruktion, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11964.
Texto completoChaiwan, Pramote. "NEW ACCURATE FAULT LOCATION ALGORITHM FOR PARALLEL TRANSMISSION LINES". UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/813.
Texto completoChen, Yuan. "A Fast, Passive and Accurate Model Generation Algorithm for RLCG Transmission Lines with Skin Effects". University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1116250638.
Texto completoZhao, Lingyin. "Generalized Frequency Plane Model of Integrated Electromagnetic Power Passives". Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/27692.
Texto completoPh. D.
Filipovic-Gledja, Visnja. "A probability based unified model for predicting electrical, mechanical and thermal characteristics of stranded overhead-line conductors". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ30086.pdf.
Texto completoNiu, Jiani. "A Study on Damage Evolution Mechanism of Hex-Chrome Free Coating/Aluminum System and a Proposed 2D Transmission Line Model Based on Experimental Results". University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1415641540.
Texto completoMonteiro, José Humberto Araújo 1981. "Resposta transitória no domínio do tempo de uma linha de transmissão trifásica considerando uma nova implementação do efeito pelicular = Time domain transient response analysis of three-phase transmission line considering a new skin effect model". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260915.
Texto completoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
Made available in DSpace on 2018-08-25T04:23:41Z (GMT). No. of bitstreams: 1 Monteiro_JoseHumbertoAraujo_D.pdf: 2599049 bytes, checksum: 247f68cef0523b44c3d1e9c69dc48119 (MD5) Previous issue date: 2014
Resumo: Este trabalho apresenta o desenvolvimento de um modelo de linha de transmissão trifásica utilizando uma nova implementação do efeito pelicular, além do estudo da resposta transitória obtida a partir do referido modelo quando surtos de manobra são simulados. A metodologia tradicionalmente utilizada para o cálculo da impedância interna de cabos sólidos cilíndricos faz uso das funções de Bessel, o que a torna complexa. A metodologia descrita por Gatous é tão precisa quanto a metodologia que utiliza as funções de Bessel e possui a vantagem de ser mais simples, visto que a solução final é um somatório cuja precisão depende da frequência estudada. O modelo desenvolvido neste trabalho emprega a metodologia de Gatous em uma linha de transmissão trifásica, cujos modos de propagação independentes são obtidos a partir da aplicação da matriz de Clarke. Para validar a metodologia de Gatous, foram calculadas a resistência e a indutância interna de cabos com raios variados em uma ampla faixa de frequências. Os resultados foram comparados aos obtidos a partir da metodologia tradicional. A metodologia de Gatous reproduziu com precisão a variação da impedância interna com a frequência. Para avaliar o funcionamento do modelo de linha de transmissão trifásico no domínio do tempo, um caso base foi estabelecido. Uma linha de transmissão trifásica de 69kV, circuito simples, foi submetida a chaveamentos de carga em duas situações distintas: chaveamento sendo executado no ponto de cruzamento com o zero da tensão e; chaveamento no ponto de 90° da tensão. Os transitórios de tensão e corrente foram obtidos a partir do modelo elaborado e comparados com os resultantes do software de análise de transitórios ATP. Os resultados alcançados reproduzem com fidelidade o comportamento transiente descrito pelo software supracitado
Abstract: This paper presents the development of a three-phase transmission line model using a new skin effect calculation and its transient response when some switching surges are applied to it. The methodology commonly used to calculate the internal impedance of solid conductors with cylindrical cross sectional area employs Bessel functions, which makes it a hard task to accomplish. Gatous, in his doctoral work, presented a new method to calculate skin effect impedance as accurate as Bessel¿s methodology with advantage of simplicity, whereas that final solution is an algebraic sum whose precision depends of frequency studied. The transmission line model developed in this work utilizes Gatous¿s method for skin effect impedance calculation in a three-phase transmission line, whose independent modes of propagation are obtained from the application of Clarke's matrix. In order to validate the mentioned methodology, internal resistances and inductances of cables with different size radii were calculated for a wide range of frequencies. The results were compared with those obtained through the traditional method, reproducing correctly the variation of the internal impedance with frequency. A base case was established to evaluate the operation of the three-phase transmission line in the time-domain model. A 69kV three-phase transmission line, single circuit, was subjected to switching load in two distinct situations: switching at zero crossing voltage and switching at voltage peak. Voltage and current transients were obtained from the developed model and compared with those derived from transient analysis software ATP. The results faithfully reproduced the transient behavior described by the above software
Doutorado
Energia Eletrica
Doutor em Engenharia Elétrica
Kim, Woopoung. "Development of Measurement-based Time-domain Models and its Application to Wafer Level Packaging". Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5012.
Texto completoTröltzsch, Uwe y Olfa Kanoun. "Standardization of diffusion and porosity models for electrochemical systems". Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-62777.
Texto completoLi, Ximing. "Damage Evolution of Pipeline API X52 Steel with Different Coating Conditions under Cathodic Protection in Soil and NS4 Solutions". University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1406291563.
Texto completoAlaya, Oussama y Maik Fiedler. "Optimal pressure control using switching solenoid valves". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200545.
Texto completoRager, David, Rüdiger Neumann y Hubertus Murrenhoff. "Remote Pressure Control - Considering Pneumatic Tubes in Controller Design". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200510.
Texto completoShi, Lei Photovoltaics & Renewable Energy Engineering Faculty of Engineering UNSW. "Contact resistance study on polycrystalline silicon thin-film solar cells on glass". Publisher:University of New South Wales. Photovoltaics & Renewable Energy Engineering, 2008. http://handle.unsw.edu.au/1959.4/41425.
Texto completoFranek, Lešek. "Vícevodičový model komunikace po venkovním elektrickém vedení". Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-256566.
Texto completoSchoene, Jens. "Analysis of parameters of rocket-triggered lightning measured during the 1999 and 2000 Camp Blanding experiment and modeling of electric and magnetic field derivatives using the transmission line model". [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE1000160.
Texto completoTitle from title page of source document. Document formatted into pages; contains viii, 184 p.; also contains graphics. Includes vita. Includes bibliographical references.
Jayasankaran, Kathik. "STRUCTURE-BORNE NOISE MODEL OF A SPUR GEAR PAIR WITH SURFACE UNDULATION AND SLIDING FRICTION AS EXCITATIONS". The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1269451200.
Texto completoWang, Chen. "Renewable Energy Integrated Power System Stability Assessment with Validated System Model Based on PMU Measurements". Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/101015.
Texto completoDoctor of Philosophy
Kaminski, Junior Joao. "Incertezas de modelo na análise de torres metálicas treliçadas de linhas de transmissão". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/10804.
Texto completoModel uncertainties pervade all stages of a structural reliability analysis, from the description of loads and the system itself, to the process by which the effect of loads on the system is evaluated. In this study, attention is focused on the last issue, specifically in the evaluation of model uncertainties on transmission lines (TL) latticed steel towers, which has remained largely ignored in previous developments of structural reliability, in part due to its elusive nature. In essence, the problem consists of evaluating the uncertainty in response predictions, once all parameters that define the external actions and the system itself have been unequivocally prescribed. The main motivation of this thesis was a study conducted by CIGRÉ on TL latticed steel towers subjected to static loads, among other exploratory assessments, which suggests that model uncertainty is a relevant factor and cannot be disregarded, could significantly influence the outcome of reliability assessments. Herein, different mechanical models of TL self-supporting towers subjected to static loads are evaluated, besides the models of towers and TL segments submitted to dynamic load due to cable rupture, adopted by being a “well defined” loading. In the static analysis, from simplified models of self-supporting towers, like adopted in usual practice of project, to more refined models are studied. The dispersion in the numeric results among the models, together with the data of static prototype tests, are used to quantify model uncertainties. The dynamic response of latticed TL steel towers subjected to cable rupture is predicted by use of various models with different degrees of sophistication or detailing. The predictions of the various models are compared with the aim of quantifying model uncertainty. Several uncertainty sources are evaluated, considering the influence of relevant factors such as: the discretization of the cable elements, the boundary conditions of the end cable elements, the constitutive laws of cables and tower members and the structural damping. Finally, possible ways to explicitly consider model uncertainty in reliability assessments and in code formulations are discussed.
Bovadilla, Robert Aleksander Gavidia. "Defasador baseado em MEMS distribuídos para aplicações em ondas milimétricas". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-23092014-100330/.
Texto completoThere is a demand for millimeter-wave (mmW) high data-rate communication systems. Systems should have small area as well as low power consumption and low cost in order to address wireless consumer applications. In this work, a low-loss distributed microelectromechanical (MEMS) phase shifter for mmW applications based on an innovative concept using distributed MEMS and slow-wave coplanar transmission lines (S-CPW) is proposed. The phase shift is achieved by releasing the ribbons of the shielding layer of the S-CPW with a HF vapor etching process. In this way the ribbons can be allows actuated when a DC voltage is applied, which changes the phase of the propagating signal. An electromechanical model and a RF model were developed using lumped elements, allowing the simulation of the dynamic behavior of the distributed MEMS and the phase shift. The phase shifter was entirely fabricated at the Laboratory of Microelectronics of the Polytechnic School from the University of São Paulo. Some electrical tests showed that the fabrication process is viable and allowed the correct release of the shielding layer of the phase shifter.
Sjödin, Mattias. "Investigating Particle Cracking in Single- and Polycrystalline Nickel-Rich Cathodes using In Situ Impedance Spectroscopy". Thesis, Uppsala universitet, Strukturkemi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-449968.
Texto completoMohamed, Imran. "The application of negative refractive index metamaterials to mm and sub-mm wavelength instrumentation". Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/the-application-of-negative-refractive-index-metamaterials-to-mm-and-submm-wavelength-instrumentation(2f650eb9-27bb-4865-81a5-d7f086c6cf22).html.
Texto completoLefort, Romain. "Contribution des technologies CPL et sans fil à la supervision des réseaux de distribution d'électricité". Thesis, Poitiers, 2015. http://www.theses.fr/2015POIT2253/document.
Texto completoEstablishing a supervisory infrastructure allows a better smart management than an expensive strengthening of distribution network to respond to new constraints at the energies control (Consumption, REN, EV ...). To transmit data, Power Line Communication (PLC) technologies present an advantage in this context. In fact, it enables a superposition of High Frequency (HF) signals on electrical signal 50/60 Hz. However, electric networks have not been developed to this application because of difficult propagation conditions. This research work makes a contribution to develop a simulation platform in objective to transmit data to 1 MHz. In first time, each network element is studied singly and in second time, together, to estimate "Outdoor PLC" transmission performance. The first element studied is the networks variation in function of frequency and time. Several 24h disturbance measurements on LV customers are presented. The second element is the transformers which established connection between Medium Voltage (MV) and Low Voltage (LV). The proposed modeling method is based on a "lumped model" and a "black box model". These models are applied to a 100 kVA H61 transformer most commonly used by French distribution system operator in rural and suburban networks. The third element is the power line used in MV and LV networks. The proposed modeling method is based on a "cascaded model" from the theory of transmission line. This model is applied to one power line used in LV underground network. Each model is obtained from various impedance measurements. To complete, an introductory study on mobile radio communication is performed to remote network distribution
Satheeskumar, Aravind. "Open Source Model of the Nordic Power System for EU Project Spine". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-286815.
Texto completoBeslutsproblem gällande drift och planering av kraftsystemet baseras ofta på storskaliga modeller och datamängder. Bristen på historiska data gällande effektflöden beror på säkerhetsrestriktioner vilket begränsar forskare till att enbart studera aggregerade nätverksmodeller. Det finns tillgängliga aggregerade data från den nordiska elmarknadsplatsen Nordpool och organisationen ENTSO-E som kan användas för att studera effektflöden mellan olika regioner, dock finns det inte direkta data för flöden inom regionerna. Det här projektet bygger på det nordiska 490-systemet, en tidigare byggd modell av det nordiska kraftsystemet. Huvudsyftet med detta arbete är att förbättra den existerande effektflödesmodellen av det nordiska kraftsystemet, för att i sin tur bli tillgänglig för multienergimodelleringar och simuleringsprogramvaran Spine. N490-modellen genererar en modell för det nordiska kraftsystemet som innehåller olika noder som presenterar ställverk med olika spänningsnivåer och modellen ger också aggregerade data för produktion, konsumtion och effektutbyte mellan de olika noderna från Nordpool. I detta projekt utvärderades olika möjliga förbättringar för modellen som syftar till att uppskatta nätverkets parametrar som kan minimera felen mellan beräkningar av flöde inom regionen och data från öppna datalagringskällor. Följande förbättringar gjordes: Först har lastens fördelning modifierats och ändrats för att matcha den regionala elkonsumtionen. Generatorer och vindkraftsparker allokerades till olika noder baserad på elhandelsområden och närhet till noderna. Databasen förbättrades för att erhålla en bättre effektbalans per område. Kraftledningarnas parametrar ändrades först till rekommenderade standardvärden, vilka sedan förbättrades genom att formulera ett optimeringsproblem för att extrahera parametrarna från markandsdata. Slutligen testades modellen genom att presentera vind- och sol-produktion som generatorer istället för som negativ förbrukning.
Cokkinides, George J. "Frequency dependent transmission line modeling with grounding representation". Diss., Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/15494.
Texto completoSeixas, Claudiner Mendes de. "Uma proposta de representação de sistemas de aterramento diretamente no domínio do tempo /". Ilha Solteira, 2017. http://hdl.handle.net/11449/151976.
Texto completoResumo: Este trabalho apresenta uma proposta de representação de sistemas de aterramento elétrico diretamente no domínio do tempo, tendo como vantagem os benefícios da modelagem realizada no domínio da frequência, com os resultados fornecidos diretamente no domínio do tempo, sem passar por transformadas inversas (Laplace ou Fourier). Os modelos no domínio do tempo são facilmente inseridos nos softwares convencionais de análise transitória, onde as tensões e correntes são melhor compreendidas. A maior contribuição deste trabalho está no desenvolvimento de uma técnica capaz de representar o aterramento com elementos discretos e positivos de circuitos (resistores-R, capacitores-C e indutores-L). Assim, o circuito equivalente representativo do aterramento será sempre um circuito possível de ser implementado fisicamente. Nesta proposta o aterramento é inicialmente modelado no domínio da frequência, sua impedância harmônica é obtida e representada por meio de elementos discretos de circuitos (RLC) associados em série e/ou paralelo. Aterramentos constituídos por um eletrodo horizontal ou uma haste vertical foram representados por meio de aproximação usando o método dos mínimos quadrados (vector fitting), que permite obter a função racional equivalente à admitância do aterramento, a partir da qual são extraídos os ramos de circuitos e consequentemente o circuito equivalente. Apesar de ser possível representar uma infinidade de aterramentos, dependendo do comprimento e diâmetro do eletrodo/ha... (Resumo completo, clicar acesso eletrônico abaixo)
Doutor
Muot, Nathanaël. "Stratégies d’hybridation de méthodes de simulation électromagnétique FDTD/MTL : Application à l’étude de grands systèmes complexes". Thesis, Toulouse, ISAE, 2013. http://www.theses.fr/2013ESAE0019/document.
Texto completoIn this thesis, we present a strategy based on a hybrid approach in the timedomain, by coupling 3D method (FDTD) with a multi-conductors transmission line (MTL)method, in order to simulate complex large scale electromagnetic problems. This reportgives the theoretical and numerical elements for coupling these approaches for two kindof problems, which are the multi domains approach and the multi scale approach. Themultiple domains approach is an extension of the classical FDTD method taking into accountseveral 3D subdomains, interconnected by a wire network, on which a 1D transmission lineformalism is used. The main issues are, on one hand to have an implicit expression ofthe electromagnetic field in the transmission line approach, and on the other hand to beable to take into account the ground effects on the induced currents, on the transmissionline parameters and on the electromagnetic field. The multi scale approach is developed toextend the capabilities of FDTD to deal with complex cables routing. We assume that thecross section of the cables are smallest than the cell size, and in these problems, the 1Dtransmission line problem is physically included in the 3D global computational domain.The work done in this thesis leaded to a new field to transmission line coupling based onthe common mode current, and an evaluation of the transmission. line parameters basedon a Laplace equation resolution in 2D. In this work, we have elaborated and proposedefficient numerical strategies for the computation of electromagnetic induced effects on largeand complex sites, composed of several interconnected distant buildings. An application tolightning problems have been done
Robinson, Robert Allen. "An Electroacoustic Analysis of Transmission Line Loudspeakers". Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14579.
Texto completoVenkateswaran, Ajay. "Analysis of planar EBG structures using transmission line models". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40812.
Texto completoLes solutions analytiques basées sur des lignes de transmission ont simplifié l'ingénierie de circuits micro-ondes complexes, tel que les EBG. La présente thèse étudie les structures coplanaires EBG à partir d'éléments discrets et de modèles de lignes de transmission, auxquels sont ensuite appliquées des formules analytiques. Grâce à cette approche, un logiciel a été développé permettant de prédire les caractéristiques de dispersion de ces structures périodiques en quelques secondes seulement. Les structures coplanaires EBG contenant des sections courbes sont étudiées et un modèle de circuit équivalent à la portion courbe est proposé. L'analyse des structures EBG commence par une simple géométrie 1D, puis est étendue à des géométries 2D plus complexes. Le résultat des simulations analytiques est évalué par rapport au résultat des simulations analogues. Lorsque les sections courbes sont incluses, le début de la bande interdite est porté en deçà de 1GHz, rendant la structure plus intéressante pour le filtrage basse fréquence omni- directionnel.
Seixas, Claudiner Mendes de [UNESP]. "Uma proposta de representação de sistemas de aterramento diretamente no domínio do tempo". Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151976.
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Este trabalho apresenta uma proposta de representação de sistemas de aterramento elétrico diretamente no domínio do tempo, tendo como vantagem os benefícios da modelagem realizada no domínio da frequência, com os resultados fornecidos diretamente no domínio do tempo, sem passar por transformadas inversas (Laplace ou Fourier). Os modelos no domínio do tempo são facilmente inseridos nos softwares convencionais de análise transitória, onde as tensões e correntes são melhor compreendidas. A maior contribuição deste trabalho está no desenvolvimento de uma técnica capaz de representar o aterramento com elementos discretos e positivos de circuitos (resistores-R, capacitores-C e indutores-L). Assim, o circuito equivalente representativo do aterramento será sempre um circuito possível de ser implementado fisicamente. Nesta proposta o aterramento é inicialmente modelado no domínio da frequência, sua impedância harmônica é obtida e representada por meio de elementos discretos de circuitos (RLC) associados em série e/ou paralelo. Aterramentos constituídos por um eletrodo horizontal ou uma haste vertical foram representados por meio de aproximação usando o método dos mínimos quadrados (vector fitting), que permite obter a função racional equivalente à admitância do aterramento, a partir da qual são extraídos os ramos de circuitos e consequentemente o circuito equivalente. Apesar de ser possível representar uma infinidade de aterramentos, dependendo do comprimento e diâmetro do eletrodo/haste combinado com determinadas resistividade e permissividade elétricas do solo, esse método pode não garantir que todos os elementos RLC sejam positivos. Por isso foi desenvolvido uma nova técnica e testada em aplicações com configurações de aterramento mais complexas (malhas). Essa técnica fornece resultados precisos e garante que todos os elementos RLC serão positivos. Sua validação foi realizada comparando os resultados propostos com os resultados obtidos pelo modelo de linha de transmissão (no caso de eletrodo/haste) e pelo modelo eletromagnético híbrido HEM (no caso das malhas). Essa técnica permite o uso de qualquer modelo capaz de fornecer a impedância harmônica, podendo ser aplicada a configurações genéricas de aterramento, o que a torna muito versátil e atrativa.
This work presents a proposal to represent of electrical grounding systems directly in time domain, taking into account the benefits in frequency domain modelling, without employing inverse Laplace or Fourier transforms. The time domain models are easily inserted in conventional electromagnetic transient software, where voltages and currents are better understood. The main contribution of this work is the development of a technique that can represent grounding by discrete and positive circuits elements (R-resistors, C-capacitors and L-inductors). The representation of the grounding is an electric circuit, possible to be implemented physically. Grounding systems is initially modelled in the frequency domain, where its harmonic impedance is obtained and then represented by elements of circuit (RLC) made in series and/or parallel association. Grounding systems constituted by a horizontal electrode or a vertical rod were represented by means of an approximation using the method of the least squares (vector fitting). It reproduces the rational function equivalent to the admittance of the grounding, which branches of circuits are extracted, forming an equivalent circuit. Although it is possible to represent an infinity of groundings, depending on the length and diameter of the electrode / rod combined with certain electrical resistivity and permittivity of the soil, this technique may not guarantee that all RLC elements are positive. However, a new technique was developed and tested in more complex grounding systems (grids). This technique provides accurate results and ensures that all RLC elements will be positive. Its validation was performed comparing the proposed results with the results obtained by the TLM (Transmission Line Model) employed for the horizontal electrodes and vertical rods and by the HEM (Hybrid Electromagnetic Model) employed for grounding grids. This technique allows the use of any model capable of providing harmonic impedance, and can be applied to generic ground configurations, making it very attractive to electromagnetics transient analyses.
Choong, Yew Kwan. "Advanced modal expansion techniques for the transmission line modelling method". Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403698.
Texto completoBirget, Philip Laurent Guillaume. "Evolutionary ecology of parasites : life-history traits, phenotypic plasticity, and reproductive strategies". Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/28805.
Texto completoNeto, Acácio Silva. "O modelo SLIM (\"Self-Consistently Interception Model\") para estimativa da incidência de descargas atmosféricas em estruturas - avaliação e aplicação na análise do desempenho de linhas de transmissão de energia". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/86/86131/tde-24052012-170058/.
Texto completoIn general, about 20 % to 60 % of the electric power service interruptions of distribution lines are attributed to lightning. For transmission lines, a typical figure is 70 %. The appraisal of the lightning performance of a power line is related to its mean flash collection rate, which depends on the mean ground flash density of the region and on the line exposure to direct lightning strokes. Models of different degrees of complexity are found in the literature for the estimation of lightning striking distances of objects and structures. However, besides the oversimplifications of the physical nature of the lightning discharge on which most of the models are based, till recently the tridimensional structure configuration could not be considered. This is an important limitation, as edges and other details of the object affect the electric field and, consequently, the upward leader initiation. Within this context, the self-consistently interception model (SLIM) proposed in 2006 by Becerra and Cooray is state-of-the-art leader inception and propagation leader model based on the physics of leader discharges which, unlike the other existing models, enables the tridimensional geometry of the structure to be taken into account. For the validation of the model, data obtained in rocket-triggered lightning experiments were used and an excellent agreement was found between measured and calculated leader stabilization electric fields as a function of the height of the rocket. This work describes the most important aspects of the new model and presents a comparative analysis of SLIM and other well-known model such as the Electrogeometric Model (EGM), Erikssons Model, and Rizks Model, as well as the simplified procedure recommended by IEEE Std. 1243. The analysis is done in terms of the striking distance, attractive radius, and the flash collection rate of a transmission line, as well as on its lightning performance, discriminating between the failure rates caused by shielding failure and backflashover.
Daltin, Rodrigo Serra. "Representação modal alternativa de linhas de transmissão trifásicas simétricas não idealmente transpostas /". Ilha Solteira : [s.n.], 2006. http://hdl.handle.net/11449/87221.
Texto completoBanca: Luiz Fernando Bovolato
Banca: Afonso José do Prado
Resumo: Esta dissertação descreve um processo alternativo para decompor uma linha de transmissão trifásica, simétrica e não transposta nos seus modos exatos por meio da utilização de duas matrizes de transformação. A primeira é a matriz de Clarke que desacopla a linha em suas componentes a, ß e zero. A componente ß é um modo exato enquanto que as componentes a e zero são acopladas. Em seguida, as componentes a e zero são representadas por uma linha bifásica que pode ser decomposta em seus modos exatos por meio de uma matriz de transformação adequada, cujos elementos podem ser sintetizados, no domínio do tempo, por técnicas de aproximações por curvas. O método pretende unir as vantagens da matriz de transformação exata (que produz modos exatos) com as vantagens da matriz de Clarke, que é real, independente da freqüência e facilmente representável em programas que realizam simulações de transitórios, como é o caso do EMTP. Assim, o método pode ser utilizado em situações em que o acoplamento entre as componentes a e zero não possa ser desconsiderado. O processo foi utilizado para simular a energização de uma linha trifásica, sem transposição, com um plano de simetria vertical, 440 kV e comprimento de 500 km que foi representada no domínio modal por meio do método proposto e também por meio do uso da matriz de autovetores (como sendo a matriz de decomposição modal). O método é coerente, pois foram obtidos resultados semelhantes com os dois métodos de decomposição modal, enquanto que com o uso somente da matriz de Clarke, verificou- se certa diferença em relação aos valores esperados.
Abstract: This dissertation describes an alternative procedure to decompose a non-transposed threephase transmission line into exact modes, by using two transformation matrices. The first one is Clarke's matrix, which separates the line into quasi-modes a, ß e zero. The ß component is an exact mode while a and zero are coupled. After that, the coupled components are represented by using a two-phase transmission line without a vertical symmetry plane that can be decomposed with a modal transformation matrix whose elements can be achieved, in timedomain, through standard curve-fitting techniques. The method intends to join the Clarke's matrix advantages which crucial aspect is being real, frequency-independent and easily represented in computational transient programs (EMTP) with eigenvector's matrix used in situations where the coupling between a and zero components cannot be disconsidered. The process was used to energize a three-phase transmission line with a vertical symmetry plane, which nominal voltage is 440kV and its length, 500km. It was represented in the modal domain by considered method and, on the other hand, by using eigenvector's matrix (as being the decomposition matrix). In fact, the obtained results had shown that the method is coherent, because it is obtained similar results with the application of the two mentioned modal decomposition methods, whereas with the use of Clarke's matrix, a perceptible difference in relation to the expected values was verified.
Mestre
Jin, Won Tae. "Circuit models for a millimeter-wave suspended-microstrip line discontinuity". Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA240906.
Texto completoThesis Advisor(s): Atwater, Harry A. Second Reader: Janaswamy, Rama. "September 1990." Description based on title screen as viewed on December 29, 2009. DTIC Identifier(s): Suspended striplines, microstrip lines, equivalent circuits, program listings, theses. Author(s) subject terms: Suspended-microstrip line, step discontinuity, equivalent circuit model, step-change. Includes bibliographical references (p. 60). Also available in print.
Wang, Xi. "Corrosion Protection of Aluminum Alloy 2024-T3 by Al-Rich Primer". The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1557143060015145.
Texto completoSun, Fengyuan. "Analyse et caractérisation des couplages substrat et de la connectique dans les circuits 3D : Vers des modèles compacts". Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0073/document.
Texto completoThe 3D integration is the most promising technological solution to track the level of integration dictated by Moore's Law (see more than Moore, Moore versus more). It leads to important research for a dozen years. It can superimpose different circuits and components in one box. Its main advantage is to allow a combination of heterogeneous and highly specialized technologies for the establishment of a complete system, while maintaining a high level of performance with very short connections between the different circuits. The objective of this work is to provide consistent modeling via crossing, and / or contacts in the substrate, with various degrees of finesse / precision to allow the high-level designer to manage and especially to optimize the partitioning between the different strata. This modelization involves the development of multiple views at different levels of abstraction: the physical model to "high level" model. This would allow to address various issues faced in the design process: - The physical model using an electromagnetic simulation based on 2D or 3D ( finite element solver ) is used to optimize the via (materials, dimensions etc..) It determines the electrical performance of the via, including high frequency. Electromagnetic simulations also quantify the coupling between adjacent via. - The analytical compact of via their coupling model, based on a description of transmission line or Green cores is used for the simulations at the block level and Spice type simulations. Analytical models are often validated against measurements and / or physical models
Asti, Gislaine Aparecida [UNESP]. "Um procedimento de estimação de parâmetros de linhas de transmissão baseado na teoria de decomposição modal". Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/87128.
Texto completoCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo deste trabalho é mostrar uma metodologia para estimar os parâmetros de linhas de transmissão. O método é baseado na teoria de decomposição modal de linhas de transmissão e é desenvolvido a partir das medições das correntes e tensões nos terminais da linha. Conforme testes realizados por Kurokawa, et al., (2006), o método de estimação de parâmetros é exato se a matriz de decomposição modal é conhecida. Desse modo, neste trabalho, o método será aplicado em uma linha de transmissão trifásica de 440 kV não transposta, em uma frequência de 60 Hz, para vários comprimentos de linhas, onde será utilizada a matriz de Clarke como sendo uma matriz de decomposição modal
The objective of this work is to show a methodology to estimate the transmission lines parameters. The method is based the theory of modal decomposition of transmission lines and is developed from measurements of currents and voltages at the terminals of the line. According to tests realized by Kurokawa, et al. (2006), the method of parameter estimation is exact if the modal transformation matrix is known. Thus, in this work, the method will be apllied in three phase transmission line of 440 kV non transposed, in a frequency of 60 Hz, for various lengths of lines, were the matrix will be used Clarke as a modal decomposition matrix