Дисертації з теми "Single stage design"
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1
Szirti, Daniel. "Development of a single-stage implosion-driven hypervelocity launcher." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112585.
Повний текст джерелаАнотація:
The present study deals with the development of a single-stage implosion-driven hypervelocity launcher. A thin-walled tube filled with helium surrounded by explosives acts as a driver for the launcher. Implosion of the tube drives a strong shock that reflects back and forth between the projectile and the implosion pinch, generating very high temperatures and pressures. Simple analytic models were used to approximate the performance of the pump tube and its use as a driver for a launcher. Experiments to evaluate the implosion dynamics and performance of the pump tube were carried out, and implosion-driven launcher experiments demonstrated muzzle velocities above 4 km/s with 5-mm-diameter aluminum projectiles. Projectile integrity was verified by high-speed photography. Disagreement of experimental data with the analytical models of performance is mostly due to failure to seal the chamber of the launcher, resulting in loss of driver gas, and pump tube expansion, which weakens the precursor shock.
2
Pneumatikakis, Aristodimos. "Modelling, analysis and design of higher-order single-stage sigma-delta modulators." Thesis, Imperial College London, 1999. http://hdl.handle.net/10044/1/7582.
Повний текст джерела
3
Cheng, Yongjie. "Design and Realization of a Single Stage Sigma-Delta ADC With Low Oversampling Ratio." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1561.pdf.
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4
Lessing, Marlon Henrique. "Analysis, design and implementation of single-stage high-frequency-isolated DC-AC flyback converters." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/2410.
Повний текст джерелаАнотація:
Esta dissertação propõe a análise de dois conversores de estágio único, isolados em alta frequência e adequados para aplicações de conexão à rede elétrica. Inicialmente, é introduzida uma nova estratégia de modulação para o conversor flyback bidirecional com conexão diferencial. Esta modulação melhorada proporciona melhor desempenho, reduzindo os valores de corrente RMS para cada componente do circuito, contribuindo assim para a redução das perdas por condução. As análises estáticas do conversor operando em ambas estratégias de modulação alternativa e original são apresentadas. A análise dinâmica também é realizada, fornecendo a função de transferência da corrente de saída pela razão cíclica do conversor ligado à uma carga resistiva e acoplado a uma fonte de tensão. Um protótipo com potência de saída de 500 W, 20 kHz, com tensão de entrada de 70 V e 127 VRMS na tensão de saída é apresentado e os resultados experimentais que comparam a nova estratégia de modulação confirmam a análise teórica e desempenho superior. Uma tensão de saída com baixa THD é alcançada para ambas estratégias de modulação, operando em malha aberta em no modo de condução contínua. O segundo conversor é um flyback com grampeamento ativo adequado para ser utilizado como um micro-inversor em aplicações de energias renováveis. As principais características da topologia são o relativo baixo número de componentes, o isolamento em alta frequência, possibilidade de ser utilizado como elevador de tensão de saída e operação em ZVS. O grampeamento ativo permite recuperar a maior parte da energia armazenada na indutância de dispersão dos indutores flyback e, assim, uma melhoria na eficiência do conversor é atingida. A análise estática é fornecida para o conversor operando em CCM. Além disso, uma função de transferência da corrente de saída pela razão cíclica é apresentada para uma carga resistiva na saída. Para este conversor duas frequências de comutação de 100 kHz e 50 kHz foram testadas num protótipo construído para 500 W, com tensão de entrada de 70 V e tensão de saída de 127 VRMS.This thesis proposes the analysis of two single-stage high-frequency isolated converters suited for grid-tied applications. Firstly, a new modulation strategy to the bidirectional flyback converter with differential output connection is introduced. This improved modulation provides better performance by reducing the RMS current values for every circuit element, thereby contributing to reduced conduction losses. The static analyses of the converter operating in both the original and the alternative switching strategies are presented. Dynamic analysis is also performed, providing the output-current-to-duty-cycle transfer function of the converter connected to a resistive load and coupled to an output voltage source. A 500 W, 20 kHz, 70 V input voltage and 127 VRMS output voltage prototype is presented and experimental results comparing the new modulation strategy to the original confirm the theoretical analyses and superior performance of the alternative switching strategy. A low THD output voltage is achieved for both switching strategies, operating in open loop and in continuous conduction mode. The second converter is an active-clamping flyback converter suitable to be used as a microinverter in renewable energy applications. The main features of the topology are the relatively low component count, high-frequency isolation, voltage step-up capability and zero voltage switching. The active clamping allows to recover most of the energy stored in the flyback inductors’ leakage inductance and thus an improvement on the system efficiency is achieved. The static analysis for CCM operation is provided. In addition, an output-current-to-duty-cycle transfer function for a resistive load connected to the output of the converter is presented. Two switching frequencies of 100 kHz and 50 kHz were tested in a prototype built for 500 W, 70 V input voltage and 127 VRMS output voltage.
5
Le, Toan T. "A Single-Stage Passive Vibration Isolation System for Scanning Tunneling Microscopy." DigitalCommons@CalPoly, 2021. https://digitalcommons.calpoly.edu/theses/2272.
Повний текст джерелаАнотація:
Scanning Tunneling Microscopy (STM) uses quantum tunneling effect to study the surfaces of materials on an atomic scale. Since the probe of the microscope is on the order of nanometers away from the surface, the device is prone to noises due to vibrations from the surroundings. To minimize the random noises and floor vibrations, passive vibration isolation is a commonly used technique due to its low cost and simpler design compared to active vibration isolation, especially when the entire vibration isolation system (VIS) stays inside an Ultra High Vacuum (UHV) environment. This research aims to analyze and build a single-stage passive VIS for an STM. The VIS consists of a mass-spring system staying inside an aluminum hollow tube. The mass-spring system is comprised of a circular copper stage suspended by a combination of six extension springs, and the STM stays on top of the copper stage. Magnetic damping with neodymium magnets, which induces eddy currents in the copper conductor, is the primary damping method to reduce the vibrations transferred to the mass-spring system. FEMM and MATLAB® are used to model magnetic flux density and damping coefficients from eddy current effect, which will help determine the necessary damping ratios for the VIS. Viton, which demonstrates a high compatibility with vacuum environments, will also serve as a great damping material between joints and contacts for the housing tube. Viton will be modeled as a Mooney-Rivlin hyperelastic material whose material parameters are previous studied, and Abaqus will be used as a Finite Element Analysis software to study the Viton gaskets’ natural frequencies. The natural frequencies of the aluminum hollow tube will also be investigated through Abaqus.
6
Yilmaz, Hasan. "Design, Application And Comparison Of Single Stage Flybackand Sepic Pfc Ac/dc Converters For Power Led Lighting Application." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615097/index.pdf.
Повний текст джерелаАнотація:
In this work, single stage power factor corrected AC/DC converters for LEDssingle stage Flyback converter having different configuration from the traditional Flyback and single stage SEPIC converter is investigated. The study involves analysis, circuit design, performance comparisons and implementation. The study covers LEDs
their developments, characteristics and state-of-art in this new technology. The circuits are investigated by means of computer simulations. Operating principles and operating modes are studied along with design calculations. After applying prototypes in laboratory, the simulation results and theoretical analyses are confirmed. The single stage Flyback converter has high voltage input (220-240 Vac), and the output feeds up to 216 HB-LEDs, with the ratings of 24 V, 3.25 A with 90 W. The single stage SEPIC converter with universal input (80-265 Vac) has an output that feeds 21 power LEDs, with 67 V, 0.30 and 20 W ratings.
7
Wen, Hao. "High-Efficiency and High-Frequency Resonant Converter Based Single-Stage Soft-Switching Isolated Inverter Design and Optimization with Gallium-Nitride (GaN)." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/105134.
Повний текст джерелаАнотація:
Isolated inverter can provide galvanic isolation which is necessary for some applications with safety regulations. Traditionally, a two-stage configuration is widely applied with isolated dc-dc stage and a sinusoidal pulse-width-modulated (SPWM) dc-ac stage. However, this two-stage configuration suffers from more components count, more complex control and tend to have lower efficiency and lower power density. Meanwhile, a large dc bus capacitor is needed to attenuate the double line frequency from SPWM for two-stage configuration. Therefore, the single-stage approach including an isolated dc-rectified sine stage and a line frequency unfolder is preferable. Since the unfolder circuit is at line frequency being almost lossless, the isolated dc-rectified sine stage becomes critical.
However, the relevant research for the single-stage isolated inverter is limited. People either utilize PWM based converter as dc-rectified sine stage with duty cycle adjustment or apply SRC or LLC resonant converter for better soft switching characteristics. For PWM based converter, hard switching restricts the overall inverter efficiency, while for SRC/LLC, enough wide voltage gain range and full range ZVS are the major issues.
This dissertation aims to provide solutions for a high-efficiency, high-frequency resonant converter based single-stage soft-switching isolated inverter design. The LLC and LCLCL resonant converters are applied as the isolated dc-rectified sine stage with variable frequency modulation (VFM). Therefore, the rectified sine wave generation consists of many dc-dc conversion with different switching frequencies and an efficient dc-rectified sine stage design needs each dc-dc conversion to be with high efficiency.
This dissertation will first propose the optimization methods for LLC converter dc-dc conversion. ZVS models are derived to ensure fully ZVS performance for primary side GaN devices. As a large part in loss breakdown, the optimization for transformer is essential. The LLC converter can achieve above 99% efficiency with proposed optimization approach. Moreover, the channel turn-off energy model is presented for a more accurate loss analysis.
With all the design and optimization considerations, a MHz LLC converter based isolated inverter is designed and a hybrid modulation method is proposed, which includes full bridge (FB) VFM for output high line region and half bridge (HB) VFM for output low line region. By changing from FB to HB, the output voltage gain is reduced to half to have a wider voltage gain range. However, the total harmonic distortion (THD) of output voltage at light load will be impacted since the voltage gain will be higher with lighter load at the maximum switching frequency.
A MHz LCLCL converter based isolated inverter is proposed for a better output voltage THD at light load conditions. The paralleled LC inside the LCLCL resonant tank can naturally create a zero voltage gain point at their resonant frequency, which shows superior performance for rectified sine wave generation. Besides the better THD performance, the LCLCL converter based isolated inverter also features for easier control, better ZVS performance and narrower switching frequency range.
Meanwhile, the LCLCL based inverter topology has bi-directional power flow capability as well. With variable frequency modulation for ac-dc, this topology is still a single-stage solution compared to the traditional two-stage solution including PFC + LLC configuration.Doctor of Philosophy
Inverters can convert dc voltage to ac voltage and typically people use two-stage approach with isolated dc-dc stage and dc-ac stage. However, this two-stage configuration suffers from more components count, more complex control and tend to have lower efficiency and lower power density. Therefore, the single-stage solution with dc-rectified sine wave stage and a line frequency unfolder becomes appealing. The unfolder circuit is to unfold the rectifier sine wave to an ac sine wave at the output. Since the unfolder is at line frequency and can be considered lossless, the key design is for the dc-rectified sine stage. The resonant converter featured for soft switching seems to be a good candidate. However, the inverter needs soft switching for the whole range and an enough wide voltage gain, which makes the design difficult, especially the target is high efficiency for the overall inverter. This dissertation aims to provide solutions for a high-efficiency, high-frequency resonant converter based single-stage soft-switching isolated inverter design. The LLC and LCLCL resonant converters are applied as the isolated dc-rectified sine stage with variable frequency modulation (VFM). Therefore, the rectified sine wave generation consists of many dc-dc conversion with different switching frequencies and an efficient dc-rectified sine stage design needs each dc-dc conversion to be with high efficiency. The design considerations and optimization methods for the LLC dc-dc conversion are firstly investigated. Based on these approaches, a MHz LLC converter based isolated inverter is designed with proposed hybrid modulation method. To further improve the light load performance, a MHz LCLCL converter based isolated inverter topology is proposed. The paralleled LC inside the LCLCL resonant tank can naturally create a zero voltage gain point which shows superior characteristics for rectified sine wave generation. Moreover, the LCLCL resonant converter based topology has bi-directional capability as well so it can work well for ac voltage to dc voltage conversion.
8
Li, Chung-lun. "Conceptual design of single and multiple state mechanical devices : an intelligent CAD approach /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19712108.
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李仲麟 and Chung-lun Li. "Conceptual design of single and multiple state mechanical devices: an intelligent CAD approach." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237332.
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10
Bautze, Tobias. "Towards quantum optics experiments with single flying electrons in a solid state system." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENY059/document.
Повний текст джерелаАнотація:
Ce travail de thèse porte sur l’étude fondamentale de systèmes nano-électroniques,mesurés à très basse température. Nous avons réalisé des interféromètres électroniques àdeux chemins à partir d’électrons balistiques obtenus dans un gaz 2D d’électrons d’unehétéro-structure GaAs/AlGaAs. Nous montrons que la phase des électrons, et ainsileur état quantique,peut être contrôlée par des grilles électrostatiques. Ces dispositifsse révèlent être des candidats prometteurs pour la réalisation d’un qubit volant. Nousavons développé une simulation numérique évoluée d’un modèle de liaisons fortes à partirde transport quantique ballistique qui décrit toutes les découvertes expérimentales etnous apporte une connaissance approfondie sur les signatures expérimentales de cesdispositifs particuliers. Nous proposons des mesures complémentaires de ce système dequbit volants. Pour atteindre le but ultime, à savoir un qubit volant à un électron unique,nous avons assemblé la source à électron unique précédemment développée dans notreéquipe à un beam splitter électronique. Les électrons sont alors injectés depuis une boîtequantique à un train de boîte quantiques en mouvement. Ce potentiel électrostatique enmouvement est généré par des ondes acoustiques de surface créées par des transducteursinter-digités sur le substrat GaAs piézo-électrique. Nous avons étudié et optimisé chacunde ces composants fondamentaux nécessaires à la réalisation d’un beam splitter à électronunique et développé un procédé local et fiable de fabrication. Ce dispositif nous permet d’étudier les interactions électroniques pour des électrons isolés et pourra servir de basede mesure pour des expériences d’optique quantiques sur un système électronique del’état condensé. Enfin, nous avons développé un outil puissant de simulation du potentielélectrostatique à partir de la géométrie des grilles. Ceci permet d’optimiser la conceptiondes échantillons avant même leur réalisation. Nous proposons ainsi un prototype optimiséde beam splitter à électron uniqueThis thesis contains the fundamental study of nano-electronic systems at cryogenictemperatures. We made use of ballistic electrons in a two-dimensional electron gasin a GaAs/AlGaAs heterostructure to form a real two-path electronic interferometerand showed how the phase of the electrons and hence their quantum state can becontrolled by means of electrostatic gates. The device represents a promising candidateof a flying qubit. We developed a sophisticated numerical tight-binding model based onballistic quantum transport, which reproduces all experimental findings and allows togain profound knowledge about the subtle experimental features of this particular device.We proposed further measurements with this flying qubit system. With the ultimate goalof building a single electron flying qubit, we combined the single electron source that hasbeen developed in our lab prior to this manuscript with an electronic beam splitter. Theelectrons are injected from static quantum dots into a train of moving quantum dots.This moving potential landscape is induced in the piezoelectric substrate of GaAs bysurface acoustic waves from interdigial transducers. We studied and optimized all keycomponents, which are necessary to build a single electron beam splitter and built up areliable local fabrication process. The device is capable of studying electron interactionson the single electron level and can serve as a measurement platform for quantum opticsexperiments in electronic solid state systems. Finally, we developed a powerful toolcapable of calculating the potential landscapes of any surface gate geometry, which canbe used as a fast feedback optimization tool for device design and proposed an optimizedprototype for the single electron beam splitter
11
Bryan, Paul David. "Accelerating microarchitectural simulation via statistical sampling principles." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/47715.
Повний текст джерелаАнотація:
The design and evaluation of computer systems rely heavily upon simulation. Simulation is also a major bottleneck in the iterative design process. Applications that may be executed natively on physical systems in a matter of minutes may take weeks or
months to simulate. As designs incorporate increasingly higher numbers of processor cores, it is expected the times required to simulate future systems will become an even greater issue. Simulation exhibits a tradeoff between speed and accuracy. By basing experimental procedures upon known statistical methods, the simulation of systems may be dramatically accelerated while retaining reliable methods to estimate error.
This thesis focuses on the acceleration of simulation through statistical processes. The first two techniques discussed in this thesis focus on accelerating single-threaded simulation via cluster sampling. Cluster sampling extracts multiple groups of contiguous
population elements to form a sample. This thesis introduces techniques to reduce sampling and non-sampling bias components, which must be reduced for sample measurements to be reliable. Non-sampling bias is reduced through the Reverse State Reconstruction algorithm, which removes ineffectual instructions from the skipped instruction stream between simulated clusters. Sampling bias is reduced via the Single Pass Sampling Regimen Design Process, which guides the user towards selected representative sampling regimens. Unfortunately, the extension of cluster sampling to include multi-threaded architectures is non-trivial and raises many interesting challenges. Overcoming these challenges will be discussed. This thesis also introduces thread skew, a useful metric that quantitatively measures the non-sampling bias associated with divergent thread progressions at the beginning of a sampling unit. Finally, the Barrier
Interval Simulation method is discussed as a technique to dramatically decrease the simulation times of certain classes of multi-threaded programs. It segments a program
into discrete intervals, separated by barriers, which are leveraged to avoid many of the challenges that prevent multi-threaded sampling.
12
Lee, Jhou-Yan, and 李卓彥. "Design and Implementation of Interleaved Single-stage Boost-Flyback Converters." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/68548983453752901237.
Повний текст джерелаАнотація:
碩士國立成功大學
電機工程學系碩博士班
96
In this thesis, the interleaved single-stage boost-flyback converters are designed and implemented. Power factor correction and output voltage regulation can be achieved. The output power can be increased by using interleaved parallel connected operation with low input and output current ripple. Firstly, the characteristics of power factor corrector stage and DC-DC stage are discussed. The composing methods of two-stage to single-stage topologies are also mentioned. Then, the operating principle and design process of the proposed converter are presented. Finally, the proposed converters are performed with input 90~130 Vrms and output 24 VDC/200 W to verify the theoretical feasibility.
13
Kuo, Yeong Chau, and 郭永超. "Design and implementation of single stage photovoltaic energy conversion system." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/07693979424730909919.
Повний текст джерелаАнотація:
博士國立成功大學
電機工程學系
89
As opposed to conventional two-stage designs, a single stage photovoltaic (PV) energy conversion system is implemented, resulting in size and weight reduction and increased efficiency. The nonlinear output power relation of versus and the near linear relation of versus are discussed. Using as an index for current control is easier than voltage control, allowing a simpler design. The proposed current controller allows a PV energy conversion system to track the maximum power point very rapidly and smoothly. In addition, single current loop controller simplifies the conventional double loop design. The proposed controller performs maximum power point tracking (MPPT) and provides power to utilities with a unity power factor. Further, the proposed controller architecture is employed to the single-phase three-wire photovoltaic energy conversion system. The proposed system employs a three-leg inverter to control the MPPT process, the line current and neutral line current. A neutral line mode controller maintains a utility neutral line current to be zero. A line mode controller controls the line current so as to provide power to the utility with a unity power factor. The proposed system acts as a solar generator on sunny days and functions as an active power filter on rainy or cloudy days. In this thesis, the voltage and current hybrid PWM inverters using fuzzy variable structure control technique is proposed for parallel operation. The voltage-controlled PWM inverter (VCPI) unit is developed to provide a specific sinusoidal output voltage and the current-controlled PWM inverter (CCPI) units are employed to track the distributive current. Each of the VCPI and CCPI units can be operated independently. By using the fuzzy variable structure control scheme, the parallel inverters can provide excellent performance without phase-lock-loop (PLL) circuit for synchronization. The proposed scheme can result in fast dynamic response and robustness to parameter variations. Finally, computer simulations and experimental results demonstrate the superior performance of the proposed technique.
14
Chung, Yi-Chih, and 鐘乙智. "Design and Implementation of Grid-Connection Single-Stage Photovoltaic Inverter." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/82577896404555606146.
Повний текст джерелаАнотація:
碩士國立高雄第一科技大學
電子工程研究所
99
In this thesis, a grid-connection single-stage PV inverter system is presented, which can deal with solar energy and performs power conditioning. To draw maximum power from PV arrays, double-linear approximation (DLA) algorithm is incorporated to achieve maximum-power-point tracking (MPPT) for PV arrays. The DLA is based on that the trajectories of maximum power point varying with irradiation and with temperature are approximately linear, respectively. With the DLA, the inverter system can determine maximum power point instantaneously and then, calculates current command easily. Thus, complicated calculation and perturbation about an optimal point can be avoided. In this thesis a corresponding circuit to realize DLA is carried out as well, of which configuration is simple. As a result, the proposed circuit is cost-effective and can be embedded into inverter system easily. From simulated and experimental results, the proposed DLA algorithm has been verified and the feasibility of the PV inverter system is also demonstrated.
15
Tsai, Chih-Ta, and 蔡知達. "Controller IC Design for Single-stage Photovoltaic Energy Conversion System." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/07653297544789224625.
Повний текст джерелаАнотація:
碩士國立成功大學
電機工程學系碩博士班
93
In this thesis, a controller IC of signal-stage photovoltaic energy conversion system is designed by cell-based IC design flow. The advantages of the study are to reduce the circuit volume and to finish a SoC (System on Chip) product. In this study, the Verilog HDL code is written, then the code is downloaded into FPGA (Field Programmable Gate Array) chip in order to verify the functions. After the grammar and functions are corrected, the prototype chip is finished by TSMC 0.35 Cell-based Design Flow. Both the stand-alone mode and the utility mode are employed into the controller chip. The system is developed to provide the 110V/60Hz sinusoidal output voltage by voltage-controlled mode and deliver real power to the load. The excess power is supported to utility line with nearly unity power factor by current-controlled mode. Finally, experimental results of the 1kW PV energy conversion system are performed to verify the FPGA functions and simulation results of EDA (Electronic Design Automation) tool are executed to demonstrate the design of digital controller chip.
16
Lo, Chien-Yu, and 駱建宇. "Design and Implementation of Half-Bridge Single-Stage Power Converter." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/448dg3.
Повний текст джерелаАнотація:
碩士國立臺北科技大學
電力電子產業研發碩士專班
96
A novel current-fed half-bridge single-stage power converter is proposed in this thesis, which is a combination of one half-bridge PFC and one half-bridge dc/dc converter to reduce control structure and the number of switches. When PFC operating in discontinuous conduction mode and fixed switching frequency, there is power factor correction in nature, and the control process is simplified. Further, compared to voltage-fed single-stage power converter, the proposed current-fed converter is advantageous to eliminate the output filter inductor. First, this thesis recommends the differences between the voltage-fed converter and the current-fed converter, then the operation of the current-fed single-stage power converter is analyzed. Finally, make a circuit of 100 watts in order to prove the principle and theory accord.
17
Chiang, Xian-Yuan, and 江顯元. "Design and Implementation of FPGA-Based Single-Stage Flyback Converter." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/97c7km.
Повний текст джерелаАнотація:
碩士國立臺北科技大學
電力電子產業研發碩士專班
96
The objective of this thesis is to design and implement an FPGA-based single-stage flyback converter with power factor correction. Based upon the well known component placement and synchronous switching methods, the single-stage flyback converter with PFC is derived from its two-stage counterpart. The advantages of the designed and implemented single stage flyback converter with PFC include reduction of power devices and the related driver. This kind of converter becomes very promising for low power applications. The controller is realized using FPGA to provide programmable capability and digital control. The design specifications are: input voltage = 110 V/AC, 60 Hz, output voltage = 12 V/DC and the rated output power = 40 W. The small-signal model is derived for digital controller design. The derived model is confirmed by simulation and realized by FPGA. Experimental results show that the output voltage can be well regulated while keeping the input power factor greater than 95%. These results confirm the design and implementation.
18
CHIANG, MING-CHUN, and 江明駿. "Design and Implementation of a Single-Stage Full-Bridge Converter." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/gze45y.
Повний текст джерелаАнотація:
碩士國立臺北科技大學
電機工程系電力電子產業碩士專班
108
The purpose of this thesis is to design and implement a single-stage full-bridge converter. The system uses a full-bridge converter as the main architecture, combined with a dual power factor correction inductor and interleaved technology, so that the converter has excellent power factor correction capability. In addition, all switches have zero voltage conduction characteristics and the reverse recovery current of the power diode can be improved. Therefore, the switching losses and reverse recovery losses can be reduced, that is system efficiency can be higher. This thesis uses voltage loop control for output stable regulation also can be achieved. In this thesis, the microcontroller TMS320D28035 produced by Texas Instruments is used as the control core to realize the designed controller and voltage loop control method to verify the correctness and feasibility of the implemented single-stage full-bridge converter and the associated design analysis. The experimental results include input voltage AC 110V,output voltage DC48V and maximum output power500W. The experimental results show that the harmonic current meets IEC61000-3-2 Class D standard, the power factor can reach 0.98 under full load condition, and maximum efficiency is 91.24%.
19
沈煌斌. "The Design and Realization of Single-Stage Single-Switch Electronic Ballasts with High Power Factor." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/8mj6z9.
Повний текст джерелаАнотація:
碩士國立臺灣大學
電機工程學研究所
88
Due to the limited resources on earth, saving each kind of energy resource has become the most important thing in the world. And because of the quick development of economy, the proportion of illumination in Taiwan have been over 20%. As a result, how to improve the efficiency of man-made illuminants which we have today should be the main topic. The purpose of this thesis is to design a electronic ballast that is low-cost and fine-property, by using a single stage and a single switch. The whole circuit consists of an electromagnetic interference filter, a bridge rectifier, a class-E frequency converter active power factor correction circuit, and a series-resonant parallel-loaded inverter. Among four parts mentioned above, in order to lowering cost and making overhauls be more convenient, the class-E frequency converter active power factor correction circuit and the series-resonant parallel-loaded inverter is integrated into a single stage, and use a single switch witch is implemented by a power MOSFET. After understanding the operational theory on each part of the circuit and inferring the criterion which is needed for designing, we have proceeded an actual example as verification ── First, we selected basic values of every parameter. Then, we used OrCAD PSpice to model the operation of IC L6560 so we could correct the related parameters. At last, the example indeed showed the similar waveform and results with simulation: the operating frequency of the switch was about 25 kHz, the power factor was about 0.98, the crest factor of the lamp current was 1.58, the efficiency was able to reach 84% ── From this example, we know the electronic ballast is practicable , on the other hand, because only one single power MOSFET is used, the cost is much lower than two-stages and single-stage two-switchs ones.
20
Chen, Yong-shiuan, and 陳永軒. "Design and Implementation of a Quasi-Resonant Isolated Inverse SEPIC Single-Switch Single-Stage Adapter." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/42767921012472806165.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電子工程系
98
This thesis aims to design and implement a single-stage single-switch power factor correction circuit with 90~264V universal AC voltage input and 24V DC output for low-power adapter applications. A quasi-resonant isolated inverse SEPIC converter is used to regulate the output voltage and achieve high input power factor simultaneously by using a simple single-stage circuit topology. The power switch is turned on with valley-switching control and the output diode is turned off with naturally zero-current-switching. The switching losses can be reduced to increase the conversion efficiency. Compared with the conventional single-stage Flyback converter, the proposed circuit can effectively reduce the output voltage ripple to less than 1%. A 20W laboratory prototype is designed and implemented to verify the proposed single-stage converter.
21
Chen, Yi-Lin, and 陳怡伶. "Design and Implementation of a Single Stage Low Power Photovoltaic Inverter." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/w24v5m.
Повний текст джерелаАнотація:
碩士國立臺北科技大學
電力電子產業研發碩士專班
98
The Object of this thesis is to design and implement a low power single stage PV inverter using DSP to replace the traditional DC-DC and DC-AC two-stage inverter. In the proposed inverter, the core converter is constructed by using a single phase full bridge which converts low-voltage DC to AC voltage with the frequency and . In order to eliminate the dc component injected to output voltage and make isolation between Photovoltaic cell and output, an isolated transformer is added at the output of full bridge. The transformer is designed by ferrite core owning to the low switching loss, and raises the sinusoidal PWM voltage yielded by full bridge to the grid side. Two switches, which are synchronized with the switching signals of full bridge and one of switches is conducted half period of sinusoidal voltage, are utilized at output path of transformer to prevent the transformer into saturation. Furthermore, a low pass LC filter and a set of switch as freewheeling path for the inductor is added near the output side to mitigate the switching noise. Finally, some experimental results tested in a self-made inverter, 35 input and /200 / output, show the effectiveness of the proposed control strategies.
22
Chou, Tung-Kuo, and 周棟國. "On the design of Single Stage Power Factor Correction Buck Converters." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/19793935080142977834.
Повний текст джерелаАнотація:
碩士國立中央大學
電機工程研究所
96
The power electronic converter is an interface between alternating current (AC)and direct current (DC). Generally, it can be classified into three categories: AC/DC converter, DC/DC converter, and DC/AC converter. Since the power is transmitted with AC fashion, most home-electronic products should translate it to DC by two-stage solution, which consists of AC/DC converter and buck converter. In this thesis, a single-stage solution, which integrates power factor correction (PFC) circuit and buck converter, is proposed to save cost and improve power efficiency in comparison with two-stage solution. The feature of our proposed circuit can make the total power consumption identical while the input AC voltage is changed. As a result,the power consumption of home-electronic products can be reduced whether the instantaneous power increases. In addition, the behavior of proposed circuit is presented with mathematical analysis, and its function is verified by the system simulation software, Matlab/Simulink and Saber simulator. Consequently, based on our proposed circuit, the harmonic distortion of power-factor buck converter is greatly reduced, and zero phase different between input current and voltage is achieved. Furthermore, the power factor is almost approximated to 1, and the regulation of output voltage is also maintained.
23
Li, Zhu-Rong, and 李竹容. "Analysis and Design of Single-Stage AC/DC LLC Resonant Converter." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/98101607642864596172.
Повний текст джерелаАнотація:
碩士國立臺灣大學
電子工程學研究所
97
A conventional power supply was designed with two stages, the former stage function as a power factor corrector (PFC), and the latter stage is a DC/DC converter which regulates the output voltage of the system. However, the cost and energy conversion efficiency of the two-stage system is higher than a single-stage one. LLC resonant converters not only have characteristics of high efficiency and low noise but also are easy to control. This circuit topology is becoming more and more widely used in application of power conversion. The duty cycle of both MOSFETs of a LLC converter is 50% that is different from a traditional PWM converter. The output regulation is control by modulation of frequency, in the ZVS region, the energy from primary side to load increases as the switching frequency decreases. In this thesis, a single-stage LLC resonant converter which combines a boost-type PFC cell and an LLC resonant DC/DC cell is proposed. The control method of it is the same as a conventional LLC resonant converter that regulate output voltage by modulating switching frequency. When the load increases, the switching frequency decreases so that the LLC gain increases and more energy can be transferred by input inductor due to longer charging time. The proposed circuit could not only reduce components and circuit size but also increase the power conversion efficiency. It has no control of the voltage of the DC-bus capacitor because there is no separate converter that can control it as there is in a two-stage converter. The capacitor voltage is dependent on the energy equilibrium established between the energy flowing into the capacitor from the input inductor and the energy flowing out of the capacitor and transferred to the output. Therefore, the characteristics of LLC tank are investigated and a new LLC design consideration is proposed, which insures the DC-bus capacitor voltage can be kept in a tolerable region. Finally, an experimental circuit is implemented to verify the analysis.
24
Yu, Ming-Hung, and 游明弘. "Design and Implementation of a Single-Stage Interleaved AC-DC Converter." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/82289156748544487622.
Повний текст джерелаАнотація:
碩士雲林科技大學
電機工程系碩士班
98
This paper presents a single-stage interleaved flyback converter with boundary conduction mode (BCM). By using interleaved technique, the current stress of the semiconductor devices and the ripple current on the input and output side are reduced. Besides, the switching losses of the switching components are also reduced by employing BCM control. In this paper, the PWM model and Loss-Free Resistor (LFR) model are employed to analysis the small-signal model of the converter, and the Bode plots of gain and phase in frequency domain are earned by Mathcad software, which is able to determine the stability of the system and the establishment of closed-loop system of the converter. Finally, simulation and experimental results from a 480W prototype are presented to confirm the effectiveness of the proposed converter.
25
Lee, Ming-Chan, and 李明展. "Driver System Design of Single-Deck Precision Stage Driven by PMLSM." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/08341650222254800451.
Повний текст джерелаАнотація:
碩士國立臺灣大學
機械工程學研究所
99
The driver system design of single-deck precision stage driven by permanent magnet linear synchronous motors (PMLSM) in this thesis is based on a digital signal processor (DSP). The stage is composed of a carriage, four sets of PMLSM, and four sets of air bearing. Levitated by air bearings, the stage is driven directly by PMLSM which has characteristics of high speed, non-contact drive, no backlash and high acceleration because of directly driving. The related control algorithm of the driver system is based on space vector control and implemented by a DSP. The travel range of the stage is dozens of millimeters and moving among planar motion. Finally, the driver system of planar motion stage based on a DSP is fulfilled and demonstrated in this thesis.
26
Liu, You-Ting, and 柳侑廷. "The Optimization Design Study of for the Single-Stage Axial Fan." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/68b9m6.
Повний текст джерелаАнотація:
碩士遠東科技大學
電腦應用工程研究所
101
This research used the CFD simulation technology to replace the actual experiment measurements and applied tow design methods, Taguchi robust design method and ANNs-GA Optimal method, to get the blade shape parameters of the single stage axial fans which have the best performance with high static pressure characteristics under a small flow rate. In the Taguchi method, the orthogonal array is applied and five control parameters with four levels which including the pretwist angle, the forward angle, the height of blade, the ideal lift coefficient and the number of blades. Perform the CFD simulation and analyze the results by the ANOVA method to find interaction effects between the control parameters. The optimal design parameters will recommend by the ratio of the bigger then better request after the ANOVA analysis. The optimal blade performance also will confirmed by the AMCA wind tunnel measurement and it shown that upgrade 92.87% with the static pressure and 31% with the large mass flow rate. In the robust design results, there were shown that the forward angle of the blade rotor and stator is more important design factor for the high static pressure of the single stage axial fan. In the rotor blade ratio analysis, it was found that have the greater value will cause the lower static pressure performance and also found that decreasing the setting angle of blade and the pre-twist angle at the tip will get higher pressure performance relatively. On the other hand, the stator forward angle of the blade shown the opposite trend with rotor performance features, the higher angle value will improve the static pressure. In this Taguchi robust analysis, the recommend control parameters will improve the static pressure 92.87%. For the large mass flow rate goal, the pre-twist angle at the tip and the forward angle is more important design factor for the single stage axial fan. In the rotor blade ratio analysis, it was found that have the greater value will cause better maximum mass flow rate performance. As the Taguchi robust results shown, the recommend control parameters will raising 31% flow rate. For those two different blade design goals in Taguchi method that will cause different blade shape of axial fan to meet the aerodynamic characteristics requirements. We were also used turbo machinery optimum tool Fine/Design3D to get best performance blade shape for the single-stage axial fan. The Fine/Design3D is using the Artificial Neural Networks (ANN) and the Genetic Algorithms (GA) combining method to guarantee to get the global optimum result. We defined seven blade profile parameters to construct a blade shape and set the operating conditions in flow solver as same as the Taguchi method. We assigned ten geometric control parameters, the torque value as constrain, the target value for the performance requirements, ANNs samples for the database generation and GA search iterations in Fine/Design3D system for the optimization procedure. This optimization result is shown the setting angle and pre-twist angle will promote the fan performance that is same design trend of the blade shape as Taguchi method. This optimal design was confirmed by AMCA wind tunnel which improved efficiency 3%, maximum flow 7.5% and torque 16% in measurement
27
Liu, Zhi-Hao, and 劉智豪. "Modeling and Controller Design for Single-Stage Isolated High Power Factor Converters." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/90272814144793705068.
Повний текст джерелаАнотація:
碩士國立成功大學
工程科學系
88
Abstract Generally speaking, the electricity of electronic devices is supplied by a switching power supply. However the power supply will generate impulsive current with high harmonic distortion due to the influences between diode rectifier and capacitor filter. This makes the power factor degraded and leads to large amount of energy losses of power company. In order to avoid energy waste and promote electricity quality, the high power factor correction (PFC) circuits are required to be added to the power supply. There are two kinds of PFC circuits. One is passive, and the other is active. Comparing with the passive PFC circuits, active PFC circuits have inherent advantages of small volume, light weight, high efficiency and high power factor. The conventional PFC circuits are commonly two-stage. The first stage is PFC stage, and the second stage is power regulation stage. To this end, it needs two switches to be controlled. This causes more expensive and complicated. To improve the defect, we combine the two switches to form a single-stage PFC power supply. In the process of combination, the concept of dither is used. The single-stage power circuit studied in this dissertation is the combination of boost converter and flyback converter. Both of them are operating in discontinuous conduction mode. The power converter in this dissertation has inherent gift of PFC, so it needs no PFC controller. But the proper elements are of essence to make it work in right mode. We drive the small-signal model of the converter when the flyback stage working in discontinuous/continuous conduction mode. The model is verified by experimental results. Finally, Based on this model, a classical controller and variable-structure controller are designed. The experimental results show that both controllers can regulate the output voltage and keep the inherent ability of PFC of the converter. However the latter is superior to the former.
28
Yeah, Yu-Ming, and 葉鈺明. "Design and Implementation of a Full Digital Single-Stage Photovoltaic Lighting System." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/74377722101166526830.
Повний текст джерелаАнотація:
碩士清雲科技大學
電機工程研究所
97
This paper presents a digital single-stage power converter for photovoltaic energy conversion application. The presented power converter consists of a boost type resonant circuit from which both DC and AC outputs are provided. The DC output is used to charge batteries and the AC output is applied for lighting purpose. With the conditions of continuous conduction and inductive load, the switches in the boost resonant converter can be turned on with ZVS. The advantages of the proposed boost resonant converter include simple structure, multiple outputs, and high energy efficiency. The system uses the PIC18F452 microcontroller as the core control unit. The maximum power point tracking control and battery charge-discharge controls are all implemented in the single unit. The system utilizes the duty cycle modulation in the day time to control the maximum power point tracking and battery charge, and the frequency modulation in the night time to control the battery discharge for lighting fluorescent lamps. All the control algorithms finished in the same microcontroller result in simple control mechanism and circuit cost reduction. Apart from theoretical analysis, design and computer simulation, an experimental prototype converter with power output 90W is constructed. The performance of the system loaded with battery (12V/3Ah x 3 lead acid) and fluorescent lamps (T5/35W x 2) are measured. The experimental outcomes from different operation modes are found in good agreement with theoretical analysis and design. The energy efficiency of the converter when operating in charge mode is 86.63%, and operating in discharge mode is 90.26%.
29
Chung, Cheng-Han, and 鍾承翰. "Embedded Control System Design for a Dual Axes Single Stack Precision Stage." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/53305175302914724687.
Повний текст джерелаАнотація:
碩士國立臺灣大學
機械工程學研究所
101
In nowadays manufacturing and semi-conductor field, application of high precise positioning stage gradually become mature, related hardware and algorism have progressed accordingly also. However, accuracy and transient response of conventional precise positioning stage are seriously constraint by mechanism designing limitation, so this research applies an innovative design with two parallel linear motors in dual axes to drive the stage for faster response time and higher thrust force, then obtaining higher accuracy and compressing noise by designing algorism respectively. Software programming bases on embedded microprocessor Texas Instruments TMS320F28335 for positioning and servo-controlling. By applying synchronous controller to strengthen the relative robustness of dual linear motors in single axis, therefore rotation of stage can be further compressed during controlling process. Finally this research will put emphasis on discussing of sliding mode control properties and effects of input command current, both in single-axis and dual-axes controlling for better understanding the performance in practical system. Furthermore, derive a mathematical model of stage for adapting in sliding mode control with proportional, integral and derivative sliding surface to improve transient response of positioning. Angle displacement compressing will be achieved by servo control strategies; this property will heavily affect dual-axes control performance. Besides, in this research, interaction between positioning and synchronous control will be noted, which is very important in transient response.
30
Chyng, Shih-Yen, and 鍾世彥. "Design and Implementation of Single-Stage High Power Factor LED Lamp Driver." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/65848408156997833396.
Повний текст джерелаАнотація:
碩士中原大學
電機工程研究所
94
Rapid advances in material and manufacturing technologies have had significant developments in high-luminance LEDs for lighting applications. LED lamps have numerous advantages, such as up to 100,000 hours of operation life, a wide range of operation temperature, and the simplicity of a driver circuit. LED lamps work with low and safe voltage, and no ignition circuit require like fluorescent lamps. In this thesis, a high performance LED lamp driver with an improved single-stage Flyback configuration is proposed. The single-stage converter is a charge-pump PFC cell integrated with a Flyback DC/DC cell. A feedback loop is designed to regulate the LED current. A laboratory prototype, which is high efficiency and high power factor, has been built and tested. Constant current control is designed in this circuit.
31
Lin, Feng-Sheng, and 林豐盛. "Design and Implementation of FPGA-Based Single-Stage Photovoltaic Energy Conversion System." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/55459528283137694469.
Повний текст джерелаАнотація:
碩士國立成功大學
電機工程學系碩博士班
92
The design and implementation of a FPGA-based Single-stage photovoltaic（PV）energy conversion system is proposed in this thesis. The full-bridge inverter converts DC power generated by photovoltaic cells into AC power. The proposed PV energy conversion system is constructed by single stage to increase the efficiency of the system. Using FPGA as controller, the proposed maximum power point tracking strategy allows PV energy conversion system to track the maximum power point rapidly and smoothly. The system can support loads with real power and feed excess power to the utility with low harmonic distortion and unity power factor sinusoidal waveform by current mode control, or can support loads exclusively with 110V/60Hz sinusoidal voltage by voltage mode control. Then, we employ a FPGA Spartan-II-XC2S200 to realize the system controller. Finally, experimental results are performed to verify the theoretical discussion and design procedure of such a digital controllerd PV energy conversion system.
32
Wang, Chih Ping, and 王致平. "The Analysis And Design of The Single-medium,Two-stage Refrigeration System." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/51370269963254470930.
Повний текст джерелаАнотація:
碩士國立臺灣大學
機械工程學系研究所
86
The purpose of this research focuses on developing the single-medium (single refrigerant R22), two-stage(compressor and ejector) refrigeration system. In the first stage ordinary R22 compressor is used and in the second stage the ejector is adopted to reach the low temperature (-40 Celsius degree) by means of two-stage compression than single-stage compression which is unable to reach the same performance. The thesis first utilizes one-dimensional equal-pressure mixing model theory to analyze the performance of ejector. Then we analyze and design the whole system of the single-medium, two-stage refrigeration system progressively. The system analysis shows that the high-temperature, high-pressure fluid in the exit of compressor can be utilized to proceed the second-stage compression. The single-medium, two-stage refrigeration system can achieve higher compression ratio and lower temperature than normal single-compressor refrigeration systems. After testing the prototype machine, the results are used to calibrate the parameters of the ejector and the performance of the whole system is re-evaluated. We find that although the results are different from the experimental outcomes quantitatively but have high consistency qualitatively compared with the experimental results.
33
Liao, Hsuan-yi, and 廖軒誼. "Design of Buck LED Driver Circuits with Single-stage Power Factor Correction." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/71915698061730145384.
Повний текст джерелаАнотація:
碩士國立中山大學
電機工程學系研究所
98
This thesis is to design an LED driver circuit with constant output current and Power Factor Correction(PFC) control. Switching power converter is applied for power stage of the LED driver circuit, a non-insulated Buck converter without transformer is used, and the inductor current of Buck converter is operating in Continuous Conduction Mode(CCM). According to the operating principle of Buck converter, the equivalent mathematical model and system block diagram is developed to establish the traditional closed loop PFC control circuit. The controller parameters are set up by time-domain and frequency-domain analysis to achieve the goal with constant output current and PFC control. Furthermore, the thesis presents a more effective PFC control method to reduce the cost of multiplier used in traditional PFC control method and overcome the congenital defect of Buck converter. Both two PFC control methods are confirmed and compared by simulation and experiment. The results show that the proposed control method has more effective performance and achieve constant output current for LED with high power factor by 0.966 under full-load condition.
34
Wu, Wen-yuan, and 吳文源. "Design of Buck LED Driver Circuits with Single-stage Power Factor Correction." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/09687550185774942582.
Повний текст джерелаАнотація:
碩士國立中山大學
電機工程學系研究所
98
In the thesis, LED driver circuits which are applied in low power lighting LED with constant output current and Power Factor Correction are presented. The non-isolated Buck converter are used for the LED drivers. According to different operating mode of inductance current, Power Factor Correction are realized with both the method of Voltage Follower Approach Control under Discontinuous Conduction Mode and the method of Nonlinear Carrier Control under Continuous Conduction Mode. NLC doesn’t need the multiplier which is used in traditional power factor correction, therefore NLC can reduce the system cost. The designed circuits are verified by simulation of IsSpice software and practical experiments. From simulation and experimental results, it shows the proposed approaches achieve the goal with high power factor and constant output current.
35
Yen, Chun-Hsien, and 嚴俊顯. "Design and Implementation of a Single-Stage High-Power-Factor LED Driver." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/80572969252258536446.
Повний текст джерелаАнотація:
碩士義守大學
電機工程學系碩士班
99
Compared with traditional lighting sources, the light-emitting-diodes (LEDs) have features of smaller size, longer lifetime, higher brightness, harder to be broken and free of mercury; they are suitable for energy-saving lighting applications nowadays. The traditional three-stage LED driver is composed of an AC-DC boost converter for power factor corrections, an isolated DC-DC converter as a power control stage, and a buck converter for achieving constant current control. The drawbacks of the conventional driver are bulky volume, large losses, and large number of circuit component. The interleaved boost converter operated in discontinuous mode allows the input current in phase with input voltage for achieving high power factor and obtaining zero-voltage-switching. The LLC resonant converter has the advantages of low switching losses, high efficiency and low electromagnetic interference, etc., so the converter is widely used in various power conversion systems. The proposed driver in the thesis, which combines above two converters into a single-stage structure, not only has the advantages of both converters, but also reduces the number of circuit component. Finally, experimental results from a prototype driver are compared with simulated ones from the IsSpice software to verify the feasibility of the presented circuit.
36
Chen, Po-Hsun, and 陳博勳. "Design of Single-Stage Resonant Converters Using Piezoelectric Transformer for Driving LED." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/34994367661622805206.
Повний текст джерелаАнотація:
碩士國立聯合大學
電機工程學系碩士班
99
This thesis investigates steady-state electrical characteristics of piezoelectric elements under temperature variations and presents a design procedure of a high-frequency power converter based on piezoelectric transformers for driving light-emitting diodes (LED). Investigations on steady-state responses of piezoelectric elements include piezoelectric transformers and piezoelectric actuators. In this thesis, a set of modified parameters in conventional equivalent circuit of piezoelectric transformers has been derived with the help of experimental studies. The effectiveness of the equivalent circuit with the derived parameters has been verified with results from simulations and practical measurements. In the aspects of designing LED driving circuit on piezoelectric transformers, the basic features of LED driving with AC source are first addressed. Then, a high-frequency power converter based on piezoelectric transformers is designed for driving LED. The proposed high-frequency converter composed of a half-bridge topology and a piezoelectric transformer has a number of advantages; i.e. intrinsic over current protection, lower electric magnetic interferences (EMI) and the current sharing problem in sets of anti-parallel LED array can be solved easily. Considering the requirements in practical applications, issues regarding the improvement of power factor, the elimination of effects of temperature on LED currents have been investigated.
37
Yi-ChuanTsai and 蔡義傳. "Design and Implementation of Single-Stage LED Driver with High Frequency Pulse." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/72824118983688888400.
Повний текст джерела
38
Lai, Jian-Hong, and 賴建宏. "Design and Implementation of Single-Stage Forward Converter with Power Factor Correction." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/4d7q34.
Повний текст джерелаАнотація:
碩士國立臺北科技大學
電力電子產業研發碩士專班
95
The objective of this thesis is to design and implement single-stage forward converter with power factor correction. Its advantage is to improve power factor and reduce input current harmonics. The power device for power factor correction and DC/DC conversion is merged for the single-stage forward converter and thereby reducing the number of power device and cost. The control IC is NCP1651 of ON Semiconductor. The specifications of the designed converter include 110 V/AC of input and 48 V/DC, 100W of output. Experimental results show that the designed and implemented converter works from no load to fully load. Moreover it is shown that its power factor higher than 95% and efficiency more than 80%. These results verify the theoretical analysis, design and implementation.
39
Lai, Chuan-Wen, and 賴景文. "Design and Implementation of single-stage boost converter in wind power system." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/9m2fgk.
Повний текст джерелаАнотація:
碩士國立虎尾科技大學
材料科學與綠色能源工程研究所
96
The present study was aimed at improving the power management system of small-scale wind turbine generator. Pursuant to this objective, a test bench was built to test the output power of small-scale wind turbine generator. We also introduced a new non-inductor type boost switching circuit to the power management system to improve the power transformation efficiency. The test bench was constructed by the PC with data acquisition system, an 180V brush DC motor through the coupling direct drive wind-driven generator, and imitate to electrical load by boost switching circuit. This experiment was performed in constant current, constant resistance, and constant voltage mode through electrical load. We used PC, microchip microcontroller dsPICF4011, Labview software and designed interface circuit to develop data acquisition system. Data acquisition system measured the output power, voltage and current before boost conversion, voltage and current after boost converter of the inductor or non-inductor type boost converter in assigned duty cycle and different motor rotational speed. The experimental results showed that under constant current mode, the inductor or non-inductor type boost converter had the maximum output power when duty cycle at 50%. Under constant current mode, when duty cycle opened lower than 60%, the output power was the same in both test modes. The output power transformation efficiency of inductor type boost converter was better than non-inductor type. When duty cycle opened larger than 60%, the inductor type boost converter had the better output power, and the non-inductor type output power transformation efficiency was better than inductor type. Under constant voltage mode, the output power of inductor and non-inductor type boost converter was the same. When the rotor speed was at 900 and 1000 rpm and duty cycle opened lower than 60%, the output power transformation efficiency of inductor type boost converter was better than non-inductor type. When duty cycle opened larger than 60%, the output power transformation efficiency of the inductor type and non-inductor type boost converter are the same. When the rotor speed was at 1100 and 1200 rpm, the output power transformation efficiency of the inductor type and non-inductor type boost converter was the same.
40
Cheng, Yu-Shen, and 程裕深. "Design of a Bridgeless Single-Stage High-Power-Factor LED Driving Circuit." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/34e269.
Повний текст джерелаАнотація:
碩士國立虎尾科技大學
電機工程研究所
103
This thesis presents a bridgeless single-stage high power-factor LED driving circuit, which evolves from a bridgeless boost-type converter and a full-bridge converter. The number of diode can be reduced with cost saving as well as conduction loss decrease being followed. The dimmer was controlled based on asymmetrical pulse width modulation which can avoid the DC link voltage rising problem accompanied by power regulation. The developed circuit will operate in discontinuous conduction mode to decrease size of inductance and attain easy control feature. With the introduction of zero-voltage-switching technique, the switching losses of active switches can be reduced and circuit operating efficiency can be enhanced. The design of resonance between transformer leakage inductance and resonant capacitor further equip the diodes with zero-current-switching characteristics. In the end, 150W(150V/1A) prototype circuit is designed and developed to validate the theoretical derivation and availability of this study. From practical measurement, full-load efficiency is 93.60% while maximum efficiency reaches 94.33%. The practical measurements disclose the power factor could reach 0.99. The dimming range covers 7.5%-100% rated output power with ZVS performance.
41
Mukhopadhyay, Arpan. "Design of Two Stage Single Phase Standalone Photovoltaic System with Battery Storage." Thesis, 2016. http://ethesis.nitrkl.ac.in/9336/1/2016_MT_AMukhopadhyay.pdf.
Повний текст джерелаАнотація:
In this work, a photovoltaic system was designed that supplies a single phase standalone load at 230V, 50Hz. As PV is the only source of power and due to intermittency of solar radiation, a battery storage was added to ride through the periods of insufficient power generation by the solar arrays. Lead acid battery was chosen due to its low cost per capacity.
Also, the issue of maintaining power balance at all times is very much essential and this problem has been handled in this project in a diligent manner. For interfacing the battery to the photovoltaic system, a bidirectional DC-DC converter has been used. Maximum Power Point tracking is accomplished by a Boost converter, which also does the work of stepping up the voltage from the array into the range suitable for inverter. As the power produced by the PV array flows through the boost converter and inverter before reaching the load, it is called a two stage system. The energy balance has been accomplished without using communication infrastructure, that is all the power electronic interfaces are controlled by three independent loops. A means of knowing the exact average value of the pulsating DC bus voltage without approximations and complex computations has been demonstrated. This enables the control loops to eliminate the effect of pulsating DC bus voltage, caused by the single phase inverter, on the battery. This ensures that the battery current does not suffer from direction reversal at double the AC line frequency, especially when the PV power and load power are close enough, which is quite common in a PV system. This prevents rapid deterioration of battery lifetime.
Also, the system has been simulated in MATLAB/SIMULAINK and simulation results shows the working of Photovoltaic System.
42
Lee, Chien-te, and 李建德. "Design and Implementation of a Multi-output Single-Stage Flyback Power Factor Corrector." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/37860079467918484242.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電子工程系
101
This thesis aims to design a multi-output single-stage Flyback power factor corrector(PFC). It can be used to drive the motor and to achieve high power factor input. A commercial boundary-conduction-mode(BCM) control IC SN03P is adopted as the PFC controller. The input current can be shaped as a sinusoidal waveform in phase with the input AC grid voltage. The operating principles and design considerations are analyzed and discussed in details. A 65W laboratory prototype for the studied multi-output single stage PFC was implemented and tested. The experimental results are shown to verify the feasibility of the studied scheme. Keywords: Single-stage Flyback PFC, Boundary-conduction-mode Power Factor, Multi-output.
43
Chou, Kuan-Fu, and 周冠甫. "Design and Implementation of A Single-Stage Asymmetrical Half-Bridge LLC Resonant Converter." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/18877956350462035523.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電子工程系
103
This thesis presents a single-stage asymmetrical half-bridge LLC resonant converter, which consists of a boost-type power factor corrector (PFC) and an asymmetric half-bridge LLC resonant converter. The PFC stage adopts the voltage-follower control operating under discontinuous conduction mode. It helps to reduce the volume of the boost inductor. The current control loop is not required to reduce the circuit design complexity. By utilizing dual control function to adjust the duty cycle and the switching frequency, the proposed converter features wide range of input voltage,low output ripple,zero-voltage switching (ZVS),and zero-current switching (ZCS). This advantages are in favor of the design for high power density. The operating principle of the proposed converter has been analyzed, described and discussed in detail. The simulation using, Mathcad and SIMPLIS, were used for circuit design. The experimental results with the wide input range 85 Vac~264 Vac and an output of 19 V/120 W reveal a maximum efficiency of 90% and a maximum power factor of 0.99
44
Sung, Wen-Gui, and 宋文貴. "Structure design and characteristics measurement of a novel single-axis piezoelectric actuating stage." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/40648560226181490903.
Повний текст джерелаАнотація:
碩士清雲科技大學
電機工程研究所
98
In this thesis, the novel single-axis piezoelectric actuating stage established by us is aimed to do the step measurement and characteristic analysis. We used the 4-9-9-14 piezoelectric actuator that is made of piezoelectric buzzer developed by our lab to do the simple rotation speed measurement proving its characteristic is better. The stage could do the horizontal linear motion through pushing precise positioning stage by using the 4-9-9-14 piezoelectric actuator, and combine the figure monitor software LabVIEW and the data-mining card NI PCI-6115 to obtain the precision position signal of the linear scale. In tradition, while the piezoelectric actuator is measuring the step of stage, parameter adjustment is usually changing the degree of voltage to change stage step. However in this thesis, the real propellent voltage time of the unit time and the load condition of stage would be changed which adjust the displacement of the stage to achieve the target of stage step measurement. First, the stage is positioned with a load condition and a no load condition, furthermore, the left and right distance should be immovable, by this experience, the step ability of the 4-9-9-14 piezoelectric actuator can be known. According to the experiment result, when the propellent voltage time is the same, the step of stage to left side is almost shorter than to right side as well as the rotation speed of rotor with clockwise is smaller than rotor with counterclockwise in the rotation speed experiment, which means both results could be confirmed that the moving capability of actuator to right side is better. In conclusion, there are many accumulated push energies under large voltage condition, so the moving step would become larger, which prove the longer step distance is depending on real propellent voltage time increasing and understand the influence of stage moving step on voltage and propellent voltage time.
45
WU, PIN-SHENG, and 吳秉陞. "Design and Implementation of a Single-Stage Asymmetrical Half-Bridge Forward Resonant Converter." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/22130744581003149271.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電子工程系
104
This thesis presents a single-stage asymmetrical half-bridge forward resonant converter, which consists of a active power factor corrector and an asymmetric half-bridge forward resonant converter. The PFC stage adopts the voltage-follower control operating under discontinuous conduction mode. The current control loop is not required to reduce the circuit design complexity. The control strategy is achieved for both main switch of the PFC stage and main switch of the forward stage by controlling one PWM signal, the proposed control method is varied duty cycle to operate in discontinuous conduction mode and variable frequency to regulate the output voltage. The power MOSFETs are adopted instead of Schotky diodes for the secondary rectification. The efficiency of the studied DC/DC converter with low-voltage high-current output can be increased. The proposed converter features wide range of input voltage, low output ripple, zero-voltage switching, and zero-current switching. The experimental results from the implemented prototype converter with the wide input range 85 ~ 264 Vac and an output of 19 V/120 W reveal a maximum efficiency of 89 % and a maximum power factor of 0.98 for the full load condition. By creating a loss analysis and proposed future research directions.
46
Yu, Da-San, and 尤德生. "Design and Implementation of Single-stage Fly-back Converter with Power Factor Correction." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/7n3u3x.
Повний текст джерелаАнотація:
碩士國立臺北科技大學
電力電子產業研發碩士專班
95
The objective of this paper is to design and implement a single-stage fly-back converter with power factor correction. The input voltage is 110 V/AC and output voltage is 12 V/DC. The basic principle of the single-stage fly-back converter is analyzed, and then the design and implementation of this converter are presented. For the implementation, the control IC of NCP1651 G is used as controller. Experimental results show that the power factor is higher than 0.85 and the efficiency is greater than 80%. These results fully confirm the design and implementation.
47
WU, YAN-YONG, and 吳彥勇. "Development of a power converter for 3-power-ports with single-stage design." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/56f3uh.
Повний текст джерелаАнотація:
碩士國立虎尾科技大學
電機工程系碩士班
107
In this thesis, a single-stage isolated type power converter with three power ports is proposed the energy conversion among renewable energy port, energy storage port and dc Grid port, thus replacing traditional multistage renewable energy storage converter with a single-stage 3-port one. The power converter integrates an interleaved synchronous rectifying boost converter and bidirectional full-bridge circuit into a single-stage topology. Hence, the proposed converter will possess features of the interleaved synchronous rectifying boost converter and bidirectional full-bridge converters with bidirectional energy propagation capability and will possess the features of:(1) merging the interleaved synchronous rectifying boost converter and dual active bridge circuit into a single-stage topology with merely 4 power switches, which can regulate the renewable energy port and energy storage battery port to meet the power demand of load at the dc Grid port and effectively reduce the amount of component and cost; (2) interleaved synchronous rectifying boost converter with two inductors working in interleaved pattern, thus facilitating converter to experience greater voltage and current stresses and produce lower the current ripple. More, the energy of renewable energy port can be directly converted to energy storage battery port or to power grid dc Grid port via dual active bridge circuit; (3) the bidirectional full-bridge topology poetesses bidirectional and electrical isolation properties, thus promoting the electricity security and increasing the power capability as well as voltage rating of converter; (4) the bidirectional feature of converter enables energy the storage/release equipment to manage energy flow via DC Grid regardless of the availability of renewable power source, thus possessing the UPS capability. With the integration of two circuit structures, the proposed topology furnishes system with 3 power ports to connect renewable energy port, energy storage batteries port and dc Grid port using TMS320F28 series digital signal processor to enumerate and centrally control the PWM modules provides duty-cycle plus phase-shift control to complete 1kW power converter, the each mode conversion efficiency can reach 94%, thus deal with the power supply stability by delivering the energy from renewable energy source to power grid dc Grid directly along with the regulation of the energy storage unit.
48
侯敦喨. "Design and Implementation of Three-phase Single-stage Bridgeless Isolated Wind Power Generation Charger." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/30478044631847958080.
Повний текст джерелаАнотація:
碩士國立聯合大學
電機工程學系碩士班
104
Large and medium wind power generation system is mainly setup in a centralized manner. On the contrary, small wind power system suits for distributed applications to support the stand-alone system such as home, traffic instrument, street light and remote telecommunication system. This thesis presents a wind charger that employs the single-stage isolated three-phase bridge PFC topology based on the SEPIC converter. Fixed frequency and high PF control technique is presented for controlling the output current of the generator. It simplifies the complexity of the control circuit, reduce the generator current distortion and thus the noise and vibration. This thesis also presents a fast maximum power point tracking (MPPT) method based on generator speed control to cope with the fast wind speed variation. The MPPT also combines with a battery three-stage charging strategy that can shift the operating point to reduce the braking resistor requirement and extend the life cycle of the battery. The charger is fully digital control implemented with TI F28335 DSP IC. A 700W prototype circuit is designed and implemented. The effectiveness is confirmed with some simulation and experimental results.
49
Yu-Cheng, Shen, and 沈育成. "Design and Implementation of a Full-Bridge Converter With Single-Stage Power Factor Correction." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/09335114020034409431.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電機工程系
93
The thesis proposes the design and implementation of a full-bridge converter with single-stage power factor correction. The converter includes two major parts: a power factor correction circuit and a full- bridge DC/DC converter. The zero switching technique is used to reduce the switching loss of the DC/DC converter. In addition, a single-stage power factor correction circuit is implemented to improve the power factor in AC source. The detailed discussion and analysis are included. The IsSpice software is used to do the computer simulation and to aid the circuit design. A 576W, 48V converter has been implemented. The simulated and experimental results validate the correctness of the proposed circuit, which has good performance and meets the PFC standards.
50
chen, Hsueh-Chan, and 陳學展. "A Novel Forward Single-Stage High Power Factor Correction Converter with a Controller Design." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/wcuqbe.
Повний текст джерелаАнотація:
碩士國立成功大學
工程科學系碩博士班
92
In this thesis, the principle of the graft scheme is discussed. By means of graft scheme, the buck-boost and forward converter are combined to create a novel forward single-stage high power factor correction (HPFC) converter. The main advantages for the proposed converter are unity power factor, low voltage stress of the bulk capacitor, and the output voltage regulation. The novel forward single-stage HPFC converter proposed in this thesis has inherent gift of power factor correction (PFC), when the first stage operates in DCM mode. Hence the PFC controller is not necessary. For the proposed converter, the circuit operation principle is analyzed and the effect due to light loads on the voltage of bulk capacitor is also discussed. It inherently exhibits high power factor because the proposed converter operates in DCM+DCM mode. In addition, it is also free to suffer from high voltage stress across the bulk capacitor at light loads. In order to investigate the dynamic behaviors,the averaging method is used to drive the dc operating point and the small-signal model. The experimental results are used to verify the accuracy of small-signal model by the illustration of Bode plots. Then, each component of the proposed converter is designed to satisfy the operation conditions. The operating point is verified by IsSpice software simulations. Finally, based on the classical control theory, a PI controller is designed to achieve output voltage regulation despite of the line voltage and load variations. A AC/DC power converter with output power 108 W is implemented in this thesis. From the results of experiment, it reveals that the designed controller can be used, without reducing the power factor of the converter, to achieve the goal of output voltage regulation despite of the line voltage and load variations. A drawback is the efficiency of the proposed converter only about 72%.