Дисертації з теми "Power Electronics and energy conversion"
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Ghosh, Suvradip. "Energy and data conversion circuits for low power sensory systems." Thesis, University of Missouri - Kansas City, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3610195.
Повний текст джерелаThis dissertation focuses on the problem of increasing the lifetime of wireless sensors. This problem is addressed from two different angles: energy harvesting and data compression. Energy harvesting enables a sensor to extract energy from its environment and use it to power itself or recharge its batteries. Data compression, on the other hand, allows a sensor to save energy by reducing the radio transmission bandwidth.
This dissertation proposes a fractal-based photodiode fabricated on standard CMOS process as an energy harvesting device with increased efficiency. Experiments show that, the fractal based photodiodes are 6% more efficient compared to the conventional square shaped photodiode. The fractal shape photodiode has more perimeter-to-area ratio which increases the lateral response, improving its efficiency.
With increased efficiency, more current is generated but the open-circuit voltage still remains low (0.3V–0.45V depending on illumination condition). These voltages have to be boosted up to higher values if they are going to be used to power up any sensory circuit or recharge a battery. We propose a switched-inductor DC-DC converter to boost the low voltage of the photodiodes to higher voltages. The proposed circuit uses two on-chip switches and two off-chip Components: an inductor and a capacitor. Experiments show a voltage up to 2.81V can be generated from a single photodiode of 1mm2 area. The voltage booster circuit achieved a conversion efficiency of 59%.
Data compression was also explored in an effort to reduce energy consumption during radio transmission. An analog-to-digital converter (ADC), which can jointly perform the tasks of digital conversion and entropy encoding, has also been proposed in this dissertation. The joint data conversion/compression help savings in area and power resources, making it suitable for on-sensor compression. The proposed converter combines a cyclic converter architecture and Golomb-Rice entropy encoder. The converter hardware design is based on current-mode circuits and it was fabricated on a 0.5 μm CMOS process and tested. Experiment results show a lossless compression ratio of 1.52 and a near-lossless compression of 5.2 can be achieved for 32 × 32 pixel image.
Chen, Zhe. "Advanced wind energy convertors using electronic power conversion." Thesis, Durham University, 1997. http://etheses.dur.ac.uk/1632/.
Повний текст джерелаBaltierrez, Jason. "Multiple Input, Single Output DC-DC Conversion Stage for DC House." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2028.
Повний текст джерелаTodeschini, Grazia. "Wind Energy Conversion Systems based on DFIG Technology used as Active Filters: Steady-State and Transient Analysis." Digital WPI, 2010. https://digitalcommons.wpi.edu/etd-dissertations/97.
Повний текст джерелаEsmaili, Gholamreza. "Application of advanced power electronics in renewable energy sources and hybrid generating systems." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1141850833.
Повний текст джерелаElamalayil, Soman Deepak. "Multilevel Power Converters with Smart Control for Wave Energy Conversion." Doctoral thesis, Uppsala universitet, Elektricitetslära, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-332730.
Повний текст джерелаRahimi, Arian. "Design And Implementation Of Low Power Interface Electronics For Vibration-based Electromagnetic Energy Harvesters." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613820/index.pdf.
Повний текст джерела10 Hz), where most vibrations exits. However, since the generated EM power and voltage is relatively low at low frequencies, high performance interface electronics is required for efficiently transferring the generated power from the harvester to the load to be supplied. The aim of this study is to design low power and efficient interface electronics to convert the low voltage and low power generated signals of the EM energy harvesters to DC to be usable by a real application. The most critical part of such interface electronics is the AC/DC converter, since all the other blocks such as DC/DC converters, power managements units, etc. rely on the rectified voltage generated by this block. Due to this, several state-of-the-art rectifier structures suitable for energy harvesting applications have been studied. Most of the previously proposed rectifiers have low conversion efficiency due to the high voltage drop across the utilized diodes. In this study, two rectifier structures are proposed: one is a new passive rectifier using the Boot Strapping technique for reducing the diode turn-on voltage values
the other structure is a comparator-based ultra low power active rectifier. The proposed structures and some of the previously reported designs have been implemented in X-FAB 0.35 µ
m standard CMOS process. The autonomous energy harvesting systems are then realized by integrating the developed ASICs and the previously proposed EM energy harvester modules developed in our research group, and these systems have been characterized under different electromechanical excitation conditions. In this thesis, five different systems utilizing different circuits and energy harvesting modules have been presented. Among these, the system utilizing the novel Boot Strap Rectifier is implemented within a volume of 21 cm3, and delivers 1.6 V, 80 µ
A (128 µ
W) DC power to a load at a vibration frequency of only 2 Hz and 72 mg peak acceleration. The maximum overall power density of the system operating at 2 Hz is 6.1 µ
W/cm3, which is the highest reported value in the literature at this operation frequency. Also, the operation of a commercially available temperature sensor using the provided power of the energy harvester has been shown. Another system utilizing the comparator-based active rectifier implemented with a volume of 16 cm3, has a dual rail output and is able to drive a 1.46 V, 37 µ
A load with a maximum power density of 6.03 µ
W/cm3, operating at 8 Hz. Furthermore, a signal conditioning system for EM energy harvesting has also been designed and simulated in TSMC 90 nm CMOS process. The proposed ASIC includes a highly efficient AC-DC converter as well as a power processing unit which steps up and regulates the converted DC voltages using an on-chip DC/DC converter and a sub-threshold voltage regulator with an ultra low power management unit. The total power consumption on the totally passive IC is less than 5 µ
W, which makes it suitable for next generation MEMS-based EM energy harvesters. In the frame of this study, high efficiency CMOS rectifier ICs have been designed and tested together with several vibration based EM energy harvester modules. The results show that the best efficiency and power density values have been achieved with the proposed energy harvesting systems, within the low frequency range, to the best of our knowledge. It is also shown that further improvement of the results is possible with the utilization of a more advanced CMOS technology.
Liddle, Marshall. "Towards a better wind power map of Nevada." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1453599.
Повний текст джерелаDavenport, Tattiana Karina Coleman. "Three-Phase Generation Using Reactive Networks." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1345.
Повний текст джерелаSamir, Karmacharya. "Modelling and control of micro-combined heat and power (CHP) to optimise energy conversion and support power distribution networks." Thesis, Northumbria University, 2013. http://nrl.northumbria.ac.uk/21424/.
Повний текст джерелаFilho, Esio Eloi dos Santos. "Conversor CA-CC com capacitor comutado com alto fator de potÃncia para o acionamento de LEDs de potÃncia." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=15719.
Повний текст джерелаEste trabalho apresenta o estudo e desenvolvimento de um conversor com capacitor comutado para o acionamento de diodos emissores de luz (LED) de potÃncia, alimentado a partir da rede elÃtrica de baixa tensÃo. Diferente dos conversores tradicionais de corrente contÃnua, a corrente direcionada aos LEDs à fornecida por meio de capacitores comutados. O conversor proposto ainda difere dos conversores convencionais baseados no capacitor comutado, pois utiliza uma indutÃncia para evitar o carregamento e o descarregamento forÃado dos capacitores comutados, reduzindo os picos de corrente e a emissÃo eletromagnÃtica do circuito. O conversor proposto apresenta correÃÃo do fator de potÃncia inerente e pode proporcionar isolaÃÃo atravÃs de capacitores. TambÃm se propÃe a utilizaÃÃo de duas topologias de filtro LC sintonizado (filtro LC paralelo e LC sÃrie) para reduzir a ondulaÃÃo da corrente de saÃda do conversor, evitando a utilizaÃÃo de capacitores eletrolÃticos. Um estudo teÃrico do conversor proposto à realizado atravÃs das anÃlises qualitativa e quantitativa, nas quais sÃo determinados os esforÃos de tensÃo e corrente nos principais componentes e tambÃm as perdas nos componentes do conversor. Um protÃtipo de laboratÃrio de 51 W com tensÃo de entrada eficaz de 220 V à projetado e testado experimentalmente. Os resultados de simulaÃÃo e experimentais sÃo apresentados e discutidos, demostrando a viabilidade tÃcnica do conversor proposto. Para a condiÃÃo de carga nominal o conversor apresenta rendimento de 75,3% e fator de potÃncia de entrada de 0,996, respeitando os limites de emissÃo de harmÃnicos determinados pela norma IEC 61000-3-2. Com a aplicaÃÃo do filtro LC paralelo, conectado em sÃrie com os LEDs, obtÃm-se ondulaÃÃo de corrente de saÃda de aproximadamente 68%, sendo essa topologia a que apresenta melhor desempenho, entre os filtros testados, estando apta a substituir o capacitor eletrolÃtico de saÃda.
This work presents a study and development of a switched capacitor-based converter to drive high power light emitting diodes (LEDs) fed from the main grid. Unlike to conventional constant current dc drivers, the current through LEDs is provided by a switched capacitor. The proposed converter approach differs from the traditional switched-capacitor-based one, because it uses an inductance to avoid the forced charging and discharging operation, reducing current spikes and EMI in the circuit. The proposed converter provides inherent power factor correction and it can provide isolation by capacitors. It is also proposed the use of two tuned LC filter topologies (parallel LC filter and series LC filter) to reduce the output current ripple, avoiding the use of large electrolytic capacitors. A theoretical analysis of the proposed converter is performed via quantitative and qualitative analysis, which determines the voltage and current efforts in main components and also losses in the converter. A 51 W, 220 V RMS laboratory prototype is designed and tested experimentally. Simulation and experimental results are presented and discussed demonstrating the technical feasibility of the proposed converter. At rated load, the converter features an efficiency of 75.3% and an input power factor of 0.996, while respecting emission limits of harmonics determined by IEC 61000-3-2. For the application of the parallel LC filter, connected in series with LED array, it is obtained output current ripple of approximately 68%. This topology presented better performance, between tested topologies, being able to replace the output electrolytic capacitor.
Wang, Tian Xiang. "Study of the integration method on the control of wind power system." Thesis, University of Macau, 2009. http://umaclib3.umac.mo/record=b2144085.
Повний текст джерелаAdamson, Jesse Timothy. "Pulse Density Modulated Soft Switching Cycloconverter." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/315.
Повний текст джерелаNathan, Kumaran Saenthan. "A novel DC-DC converter for photovoltaic applications." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/288881.
Повний текст джерелаRizet, Corentin. "Amélioration du rendement des alimentations sans interruption." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00651973.
Повний текст джерелаGonzalez, Ander. "Integration of photovoltaic sources and battery based storage systems – A DC analysis and distributed maximum power point tracking solution." Doctoral thesis, Universite Libre de Bruxelles, 2019. https://dipot.ulb.ac.be/dspace/bitstream/2013/282059/4/TOC_vf.pdf.
Повний текст джерелаDoctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
Venturini, William Alegranci. "Fonte ininterrupta de energia trifásica de alto desempenho sem transformador com dupla funcionalidade do estágio de entrada e sistema de controle digital." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/8594.
Повний текст джерелаThis master s thesis proposes a three-phase transformerless double-conversion UPS with digital control system and reduced overall cost. The topology is composed of an input stage, a battery bank, an inverter, an auxiliary circuit and transfer switches. The input stage assumes the three-phase rectifier function with LCL filter in normal operation mode and is responsible for discharge the battery bank in backup mode. This configuration reduces the system cost since an available circuit is used to discharge the battery bank. In conventional double-conversion UPS topologies the input stage remains inactive during the backup mode and an additional circuit is employed for this purpose. The auxiliary circuit is formed by an inductor and a switching leg and is used as a battery charger during normal operation mode and is additionally used to balance the bus capacitors voltages in backup mode. In this configuration, the auxiliary circuit can be designed for only a fraction of the UPS rated power, also providing lower total system cost. Transfer switches change the configuration of the input stage and the auxiliary circuit according to the UPS operating mode. The detailed operation of the topology, modelling, digital control structure, and the results obtained by simulation are showed. Finally a 20 kVA prototype is implemented and experimental results are acquired for the validation of the employed design methodology as well as the proposed circuit functionality.
Esta dissertação de mestrado propõem uma topologia de fonte ininterrupta de energia (UPS - Uninterruptible Power Supplies) trifásica de dupla conversão sem transformador com custo reduzido e sistema de controle digital. A UPS proposta é composta por um estágio de entrada, um banco de baterias, um inversor, um circuito auxiliar e chaves de transferência. O estágio de entrada assume a função de retificador trifásico com filtro LCL em modo normal de operação da UPS e é responsável pela descarga do banco de baterias em modo bateria de operação. Esta configuração reduz o custo do sistema, pois permite que seja aproveitado um circuito disponível e dimensionado para a potência nominal da UPS para a descarga do banco de baterias. Em topologias convencionais de UPSs de dupla conversão o estágio de entrada permanece ocioso durante este modo de operação e um circuito adicional é empregado para este fim. O circuito auxiliar é formado por um indutor e um braço de interruptores e é utilizado como carregador de baterias em modo normal de operação e adicionalmente é utilizado para realizar o equilíbrio das tensões dos capacitores de barramento em modo bateria. Com esta configuração, o circuito auxiliar pode ser dimensionado para apenas uma fração da potência nominal da UPS, propiciando também a redução do custo total do sistema. As chaves de transferência alteram as configurações do estágio de entrada e do circuito auxiliar de acordo com o modo de operação da UPS. É apresentada a operação detalhada da topologia, a modelagem, a estrutura de controle digital utilizada e os resultados obtidos via simulação. Por fim, um protótipo de 20 kVA é implementado e resultados experimentais são adquiridos para a validação da metodologia de projeto empregada bem como da funcionalidade do circuito proposto.
Guida, Vittorio. "Conception et réalisation d'un convertisseur DC/DC à haut rapport de conversion pour électrolyseurs." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0134.
Повний текст джерелаIn recent years, the use of electrolyzer to produce cleanly and efficiently hydrogen from renewable energy sources (e.g. wind, solar) has gained growing interest from researchers and industrial. Similarly to fuel cells, electrolyzers require power conditioning systems, such as DC/DC converters. Generally, electrolyzers need a very low DC voltage to generate hydrogen from de-ionized, pure or distilled water. For this reason, DC/DC buck converters are generally used. For electrolyzer applications, DC/DC converters must meet several challenging issues in terms of energy efficiency and output current ripple reduction. Generated high-frequency current ripples from DC/DC converter may lead to long-term degradation on electrolyzers. As a result, high-frequency current ripples can shorten the electrolyzer life span. Furthermore, the availability and reliability of DC/DC converters remain a major concern so that stand-alone power supply can guarantee a high-level of autonomy in case of electrical failures. Within the wind-H2 stand-alone power supply, DC bus is generally a high-voltage of a few hundreds of volt. Given that the electrolyzer must be supplied at a very low DC voltage, interface DC/DC converter has to present a high-conversion ratio
Lopez, Santos Oswaldo. "Contribution to the DC-AC conversion in photovoltaic systems : Module oriented converters." Thesis, Toulouse, INSA, 2015. http://www.theses.fr/2015ISAT0001/document.
Повний текст джерелаThese last years, a growing interest in power electronic systems has been motivated by the emergence of distributed renewable energy resources and their interconnection with the grid. In this context, the need of low power topologies fed by a few photovoltaic modules avoiding the use of transformers opens the study of special converters and the associated control strategies ensuring stability, reliability and high efficiency. A resulted generic device known in the commercial and scientific literature as “microinverter” or “module integrated converter” performs a plug and play product together with the PV module called an “AC module”.This work is devoted to the study of a transformer-less single-phase double-stage grid-connected microinverter. The proposed topology has a non-isolated high-gain boost type DC-DC converter and a non-isolated buck type DC-AC converter connected in cascade through a DC bus. The DC-DC converter permanently extracts the maximum power of the PV module ensuring at the same time a good performance coping with power changes introduced by the change in the environmental conditions. The DC-AC stage injects the power extracted by the DC-DC stage into the grid ensuring a high level of power quality. The research efforts focus on the involved control functions based on the sliding mode control theory, which leads to a simple implementation with a comprehensive theoretical description validated through simulation and experimental results.After giving the state-of-the-art in the first chapter, the manuscript is divided into four chapters, which are dedicated to the Maximum Power Point Tracking (MPPT), the DC-DC stage and its control, the DC-AC stage and its control and the complete microinverter. A new Extremum Seeking Control (ESC) MPPT algorithm is proposed. The single-switch quadratic boost converter is studied operating as a Loss-Free-Resistor (LFR) obtaining a high DC output voltage level with a safe operation. The full-bridge converter is controlled as a Power Source Inverter (PSI) using a simple sliding-mode based tracking law, regulating the voltage of the DC bus and then ensuring a high power quality level in the grid connection. Finally, the three building blocks are merged to obtain a sliding mode controlled microinverter constituting the main result and contribution of the work
Arroyo, Emmanuelle. "Récupération d'énergie à partir des vibrations ambiantes : dispositif électromagnétique et circuit électronique d'extraction synchrone." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00768218.
Повний текст джерелаVillalva, Marcelo Gradella 1978. "Conversor eletrônico de potência trifásico para sistema fotovoltaico conectado à rede elétrica." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260742.
Повний текст джерелаTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
Made available in DSpace on 2018-08-17T05:47:06Z (GMT). No. of bitstreams: 1 Villalva_MarceloGradella_D.pdf: 10773240 bytes, checksum: aeccba84d675a257bed00100b3d011cb (MD5) Previous issue date: 2010
Resumo: Este trabalho é uma contribuição ao estudo de conversores eletrônicos para sistemas fotovoltaicos de geração distribuída de energia elétrica. O objetivo principal é apresentar o desenvolvimento e os resultados de um conversor eletrônico trifásico para a conexão de um conjunto de painéis solares fotovoltaicos à rede elétrica de baixa tensão. São apresentados resultados experimentais e estudos teóricos sobre a modelagem e a simulação de dispositivos fotovoltaicos, a regulação da tensão fotovoltaica, o rastreamento da máxima potência e a modelagem e o controle de um conversor eletrônico de dois estágios
Abstract: This work is a contribution to the study of power converters for photovoltaic distributed generation systems. The main objective is to present the development and results of a threephase power converter for a grid-connected photovoltaic plant. The work presents experimental results and theoretical studies on the modeling and simulation of photovoltaic devices, regulation of the photovoltaic voltage, maximum power point tracking, and the modeling and control of a two-stage grid-connected power converter
Doutorado
Energia Eletrica
Doutor em Engenharia Elétrica
Fu, Hailing. "Rotational energy harvesting for low power electronics." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/59031.
Повний текст джерелаDas, Debosmita. "Advanced power electronics for hybrid energy systems." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1412940298.
Повний текст джерелаHoward, John N. "Thermophotovoltaic energy conversion in submarine nuclear power plants." Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5684.
Повний текст джерелаv ABSTRACT Thermophotovoltaic (TPV) cells allow for the direct conversion of infrared (IR) radiation to electricity, similar to when traditional solar cells are exposed to visible light. The objective of this thesis is the development of a computer model of a multijunction TPV cell designed to absorb IR radiation from the primary fluid system of a naval nuclear reactor. This model is then used to determine the feasibility of using this TPV system as a supplemental source of electrical power on a next-generation nuclear submarine. The results of this simulation indicate that the design concept presented in this thesis is a viable option and warrants further consideration and research.
Rizea, Steven Emanoel. "Optimization of Ocean Thermal Energy Conversion Power Plants." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5462.
Повний текст джерелаID: 031001365; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Marcel Ilie.; Title from PDF title page (viewed May 8, 2013).; Thesis (M.S.M.E.)--University of Central Florida, 2012.; Includes bibliographical references (p. 77-78).
M.S.M.E.
Masters
Mechanical and Aerospace Engineering
Engineering and Computer Science
Mechanical Engineering; Mechanical Systems
McPeake, F. A. "Wave energy conversion using small scale floating devices." Thesis, Queen's University Belfast, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374227.
Повний текст джерелаAhmed, Shehab. "Compact harsh environment energy conversion systems." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1289.
Повний текст джерелаZhang, Yongzheng. "Doubly-fed induction machine for variable speed energy conversion applications." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114286.
Повний текст джерелаAprès des décennies de développement, l'industrie de l'énergie éolienne fournit maintenant de 10% à 20% de la puissance produite dans les réseaux électriques. Présentement, les alternateurs asynchrones à double alimentation (DFIG) sont parmi les alternateurs les plus utilisés dans les parcs éoliens. La recherche de cette thèse avance les méthodes de contrôle des DFIGs par la présentation : (i)d'une méthode non-mécanique (sans capteur de mesure) afin de déterminer précisément la vitesse et la position du rotor, qui sont essentielles dans l'implémentation de contrôle découplée P-Q; (ii)d'une méthode de contrôle autonome de la fréquence par quoi un parc éolien îloté n'a pas à interrompre sa production mais il peut continuer à fonctionner en attente pour aider le réseau électrique à une restauration rapide. (iii) D'une méthode pour limiter le problème de déséquilibre de puissance au début de l'îlotage en utilisant l'angle d'attaque de l'éolienne pour évacuer l'excédent de la puissance éolienne.Cette thèse examine aussi l'adaptation économique requise pour rendre l'alternateur asynchrone à double alimentation, qui contient les contrôleurs conçus pour l'application éolienne, commercialisable comme moteur asynchrone à double alimentation. La recherche est basée sur l'analyse théorique, validée par simulation digitale. Une plateforme prototype d'un DFIG de 5hp, qui a été construite et testée, fournit la vérification expérimentale des résultats de la recherche.
Thorburn, Karin. "Electric Energy Conversion Systems : Wave Energy and Hydropower." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7081.
Повний текст джерелаTrilla, Romero Lluís. "Power converter optimal control for wind energy conversion systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2013. http://hdl.handle.net/10803/134602.
Повний текст джерелаWind energy has increased its presence in many countries and it is expected to have even a higher weight in the electrical generation share with the implantation of offshore wind farms. Consequently, the wind energy industry has to take greater responsibility towards the integration and stability of the power grid. In this sense, there are proposed in the present work control systems that aim to improve the response and robustness of the wind energy conversion systems without increasing their complexity in order to facilitate their applicability. In the grid-side converter it is proposed to implement an optimal controller with its design based on H-infinity control theory in order to ensure the stability, obtain an optimal response of the system and also provide robustness. In the machine-side converter the use of a Linear Parameter-Varying controller is selected, this choice provides a controller that dynamically adapts itself to the operating point of the system, in this way the response obtained is always the desired one, the one defined during the design process. Preliminary analysis of the controllers are performed using models validated with field test data obtained from operational wind turbines, the validation process followed the set of rules included in the official regulations of the electric sector or grid codes. In the last stage an experimental test bench has been developed in order to test and evaluate the proposed controllers and verify its correct performance.
Gong, Qian. "Integrated power conversion circuit for radio frequency energy harvesting." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609873.
Повний текст джерелаPresby, Andrew L. "Thermophotovoltaic energy conversion in space nuclear reactor power systems." Thesis, Monterey, Calif. : Naval Postgraduate School, 2004. http://edocs.nps.edu/npspubs/scholarly/theses/2004/Dec/04Dec%5FPresby.pdf.
Повний текст джерелаThesis Advisor(s): Gopinath, Ashok ; Michael, Sherif. "December 2004." Description based on title screen as viewed on March 13, 2009. Includes bibliographical references (p. 123-127). Also available in print.
Kamanzi, Janvier. "Thermal electric solar power conversion panel development." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2527.
Повний текст джерелаThe world has been experiencing energy-related problems following pressuring energy demands which go along with the global economy growth. These problems can be phrased in three paradoxical statements: Firstly, in spite of a massive and costless solar energy, global unprecedented energy crisis has prevailed, resulting in skyrocketing costs. Secondly, though the sun releases a clean energy, yet conventional plants are mainly being run on unclean energy sources despite their part in the climate changes and global warming. Thirdly, while a negligible percentage of the solar energy is used for power generation purposes, it is not optimally exploited since more than its half is wasted in the form of heat which contributes to lowering efficiency of solar cells and causes their premature degradation and anticipated ageing. The research is geared at addressing the issue related to unsatisfactory efficiencies and anticipated ageing of solar modules. The methodology adopted to achieve the research aim consisted of a literature survey which in turn inspired the devising of a high-efficiency novel thermal electric solar power panel. Through an in-depth overview, the literature survey outlined the rationale of the research interest, factors affecting the performance of PVs as well as existing strategies towards addressing spotted shortcomings. While photovoltaic (PV) panels could be identified as the most reliable platform for sunlight-to-electricity conversion, they exhibit a shortcoming in terms of following the sun so as to maximize exposure to sunlight which negatively affects PVs’ efficiencies in one hand. On the other hand, the inability of solar cells to reflect the unusable heat energy present in the sunlight poses as a lifespan threat. Strategies and techniques in place to track the sun and keep PVs in nominal operational temperatures were therefore reviewed.
Boström, Cecilia. "Electrical Systems for Wave Energy Conversion." Doctoral thesis, Uppsala universitet, Elektricitetslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-140116.
Повний текст джерелаFelaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 727
Michaelides, Alexandros M. "The design of switched reluctance motors for efficient energy conversion." Thesis, University of Warwick, 1994. http://wrap.warwick.ac.uk/36213/.
Повний текст джерелаKalpaktsoglou, Dimitrios. "Power factor correction for stand-alone wave energy conversion buoys." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519591.
Повний текст джерелаAyeleso, Ayokunle Oluwaseun. "An improved plasma energy conversion system for electric power generation." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2694.
Повний текст джерелаThe generation of electricity through the conventional conversion system such as thermal and hydroelectric plants may no longer be sufficient to meet the increasing demands and usage. One of the major reasons for shortage supply of electric power is due to the lack of fossil fuel and other conventional resources that are currently being used in Africa. In addition, the conversion process of the conventional system often causes pollution which contributes to global warming. Therefore, there is a need for this research to develop novel and alternative methods of generating electric power. Among these methods is the Magnetohydrodynamics (MHD) conversion system, which is a direct energy conversion system. In this system, plasma or ionised gas is directly converted into electric power with generating efficiency of about 62 %. The conversion process of the MHD system is based on the principle of Faraday’s Law of electromagnetism and fluid dynamics. The focus of the present study is to investigate alternative methods through which an MHD power generator can be coupled to the existing thermal plants in South Africa. In doing so, the thermal cycle efficiency of these conventional plants can be improved. Another goal of this study is to investigate the behaviour of an MHD generator prototype under exposure to plasma through simulation and experimentation in a laboratory setting.
Kravetz, Fábio Inocêncio. "Conversor SEPIC modificado com acoplamento magnético série e célula multiplicadora de tensão." Universidade Tecnológica Federal do Paraná, 2018. http://repositorio.utfpr.edu.br/jspui/handle/1/3201.
Повний текст джерелаThe renewable energy resources, in special the photovoltaic energy has been achieve more space in last years due to technology advances, cost reduction and decrease of the non-renewable energy sources. The photovoltaic panels in isolation or to small applications generate a low output voltage and to comply with of voltage levels provided in panel’s output to those required by electric power concessionaire is a challenge. In this work is presented a new structure modified of the SEPIC converter topology who uses the coupling magnetic series and voltage multiplier cell techniques together, in order to obtain a high voltage gain aiming at application in renewable energy resources. It was has been choosen non-isolated solution, because this present several advantages in relation to the isolated solution, such as: lower weight, volume, cost and high energy efficiency due to smaller power losses in the coupled inductors. The use leakage inductance, who is an intrinsic parameter of the a magnetic coupling, allows soft-switching operation ZCS in switch, increasing the structure’s efficiency with reduction of switching losses. During the work are perform the analysis of the operation steps of several converters as of the modified SEPIC converter and evolves by addition high voltage techniques until the structure proposed in this work. Finally, is performed the closed loop control using the analog PID controller who provides a fast response and consequent correction to possible changes in the controlled variable. The theoretical and experimental results of the proposed converter are described in this work to validate the developed analysis and demonstrate the structure’s efficiency. The prototype is developed to a application with nominal power of 200 W, nominal output voltage equal 450 V and an input voltage varying between 20 V and 40 V. The efficiency obtained to proposed converter operating in frequency of the 35 kHz in nominal power is 91,28% and efficiency equal 89,04% to nominal power in frequency of the 90 kHz.
Tymerski, Richard P. E. "Topology and analysis in power conversion and inversion." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/77852.
Повний текст джерелаPh. D.
MacRae, Angus Neil. "Economic and cost engineering aspects of wind energy conversion systems." Thesis, Robert Gordon University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258961.
Повний текст джерелаVasconcelos, Araújo Samuel [Verfasser]. "On the Perspectives of Wide-Band Gap Power Devices in Electronic-Based Power Conversion for Renewable Systems / Samuel Vasconcelos Araújo." Kassel : Kassel University Press, 2013. http://d-nb.info/1056974702/34.
Повний текст джерелаNsumbu, Cassandra Daviane. "Development of a soft-core based power electronic conversion controller." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/2379.
Повний текст джерелаThe application of digital control techniques has become dominant in power electronics owing to several advantages they present, when compared to analogue solutions. Their development is based on the use of microprocessors and microcontrollers, such as Application Specific Integrated Circuit (ASIC), Digital signal processors (DSP), Field Programmable Gate Arrays (FPGA), or a combination of these devices. This thesis presents an investigation of a soft-core based FPGA control system as a solution for power electronic applications. The aim was the development and implementation of a conversion controller, which purpose is to supply control inputs in the form of digital Pulse Width Modulation (PWM) signals, to a number of power electronic applications, such as single half and full bridge DC-DC converters, three phase and multicell inverters. The PWM control technique is achieved via their power semiconductor switching devices. These PWM control signals are necessary for the high frequency conversion of an analog input voltage (AC, DC or unregulated) to an analog output voltage of another level (AC or DC). This was intended to be achieved by exploiting and combining the advantages that FPGA and embedded processors provide such as high reconfigurability and multipurpose ability. This controller’s digital outputs, namely PWM switching signals, can be directly delivered to an analog signal amplification circuit to create an adequate voltage level before being processed by the converters’ switches.
Hostettler, Jacob. "Advanced Control of Permanent Magnet Synchronous Generators for Variable Speed Wind Energy Conversion Systems." Thesis, Southern Illinois University at Edwardsville, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1588620.
Повний текст джерелаVarious environmental and economic factors have lead to increased global investment in alternative energy technologies such as solar and wind power. Although methodologies for synchronous generator control are well researched, wind turbines present control systems challenges not presented by traditional generation. The varying nature of wind makes achieving synchronism with the existing electrical power grid a greater challenge. Departing from early use of induction machines, permanent magnet synchronous generators have become the focus of power systems and control systems research into wind energy systems. This is due to their self excited nature, along with their high power density. The problem of grid synchronism is alleviated through the use of high performance power electronic converters. In achievement of the optimal levels of efficiency, advanced control systems techniques oer promise over more traditional approaches. Research into sliding mode control, and linear matrix inequalities with nite time boundedness and H∞ performance criteria, when applied to the dynamical models of the system, demonstrate the potential of these control methodologies as future avenues for achieving higher levels of performance and eciency in wind energy.
Xu, Mingzhou. "A study of induction generator performance in a wave energy conversion system." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387930.
Повний текст джерелаJovovic, Vladimir. "Engineering of Thermoelectric Materials for Power Generation Applications." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1248125874.
Повний текст джерелаMondal, Abrez. "A PMSG-Based Wind Energy Conversion System Assisted by Photovoltaic Power." Thesis, North Dakota State University, 2012. https://hdl.handle.net/10365/26796.
Повний текст джерелаNDSU Department of Electrical and Computer Engineering
Graduate School at North Dakota State University
Maksimcev, Mirko D. "Energy considerations in power system damping by reactorcapacitor switching." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23370.
Повний текст джерелаThe analytical studies (covered in Chapter 1) reveal that the magnetic and electrostatic energy are constantly stored in the reactive components of the transmission system. The energy stored in a series compensated line is greater than the energy stored in an uncompensated line of equal transmission capability. The transient energy flow caused by characteristic switching in transmission systems is studied analytically in Chapter 2. Switching of an additional line or switching of series capacitors initiates transient charging/discharging of the line towards its new steady-state energy level which is always associated with losses. Power transfer characteristics of the systems which are equivalent in steady-state operation (parallel lines vs. an equivalent series compensated line) have quite different transient power transfer characteristics. These differences are related to different stored energies in such systems. System sources participate in all transient energy flow phenomena.
The impact of series compensation switching upon the mechanical oscillation damping was demonstrated by simulations presented in Chapter 3. Thyristor switched variable series compensation (VSC) is simulated in order to verify the conclusions of the analytical studies regarding the charging/discharging energy of the line.
The switching of reactive power components for the purpose of power system oscillation damping involves significant energy impulses in and out of the machines. Therefore, stability studies have to be performed by simulation which involves detailed representation of electromagnetic phenomena (EMTP for example).
Zoric, I. "Multiple three-phase induction generators for wind energy conversion systems." Thesis, Liverpool John Moores University, 2018. http://researchonline.ljmu.ac.uk/8387/.
Повний текст джерелаKampfe, Sara Katherine. "Processing and Conversion of Algae to Bioethanol." W&M ScholarWorks, 2010. https://scholarworks.wm.edu/etd/1539626902.
Повний текст джерелаYuen, Katarina. "System Perspectives on Hydro-Kinetic Energy Conversion." Doctoral thesis, Uppsala universitet, Elektricitetslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-181555.
Повний текст джерела