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Filtrage actif intégré reconfigurable pour la téléphonie sans fil / Reconfigurable active filtering for mobile wireless applicationAddou, Mohammed Adnan 15 December 2016 (has links)
Ce travail de thèse porte sur la conception de dispositifs filtrants accordables, c'est-à-dire pouvant commuter leurs caractéristiques d'un standard à un autre afin de réduire l’encombrement des chaines émission/réception d’un dispositif multistandard. Les filtres les plus utilisés actuellement sont des filtres acoustiques. En effet, ces filtres sont difficilement intégrables dans une technologie silicium et ils restent parmi les dispositifs passifs les plus encombrants du front-end RF. De plus, ils ne permettent pas d’avoir de bonnes performances en pertes d’insertion, en sélectivité et en accordabilité fréquentielle. De ce fait, des solutions alternatives sont à l’origine de ces travaux de thèse. Nous avons considéré tout d’abord un filtre actif qui a la possibilité de régler sa fréquence de résonnance, d’une part à la fréquence de résonnance du système Wifi et d’autre part, à la fréquence de résonnance du système Zigbee. Ensuite, une autre solution a été proposée dans le dernier chapitre qui consiste à réaliser une structure active filtrante bi-bande intégrée. Cette solution a pour avantage de récolter simultanément les données des systèmes opérant dans les deux bandes de fréquences visés. Les résultats obtenus des circuits réalisés sont validés par des simulations et de mesures. / This thesis concerns the design of tunable filter devices that can switch theirs characteristics from one standard to another in order to reduce the congestion of emission/reception chain of multi-standard systems. The most commonly used filters are acoustic filters. Indeed, these filters are difficult to be integrated in silicon technology and they remain one of the most bulky passive devices of the RF front-end. In addition, they don’t achieve good performance in insertion loss, frequency selectivity and tunability. Therefore, alternative solutions are at the origin of this thesis. An active filter is considered with the possibility of adjusting the resonance frequency: the resonant frequency of the Wifi system and the resonance frequency of the Zigbee system. Moreover, another solution is proposed in the last chapter, which consists to achieve a dual band structure of integrated active filter. This solution has the advantage to simultaneously collect data provided from the operating systems located in the two specified frequencies bands. Simulations and measurements validate the results of the realized circuits.
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Design and characterization of monolithic microwave integrated circuits in CMOS SOI technology for high temperature applicationsEl Kaamouchi, Majid 24 September 2008 (has links)
Silicon-on-Insulator (SOI) CMOS technology constitutes a good candidate for mixed signal RF CMOS applications. Due to its low junction capacitance and reduced leakage current, SOI provides reduced static and dynamic power consumption of the digital logic combined with increased cut-off frequencies. Moreover, in terms of passive device integration the major benefit of SOI when compared to the conventional bulk is the possibility to use a high resistivity substrate which allows a drastic reduction of substrate losses allowing a high quality factor of the passive devices.
Another issue is the harsh environment applications. Electronics capable of operating at high temperatures are required in several industrial applications, including the automobile industry, the aerospace industry, the electrical and nuclear power industries, and the well-logging industry. The capability of SOI circuits to expand the operating temperature range of integrated circuits up to 300°C has been demonstrated. SOI devices and circuits present advantages in this field over bulk counterparts such as the absence of thermally-activated latch up and reduced leakage current.
In this context, various topologies of integrated transmission lines and spiral inductors implemented on standard and high substrate resistivities have been analyzed over a large temperature range.
The temperature behavior of the SOI transistors is presented. The main figures-of-merit of the SOI MOSFETs are analyzed and the extraction of the extrinsic and intrinsic parameters of the small signal equivalent circuit is performed.
Also, an example of RF circuit applications of the SOI technology, based on a fully integrated Low-Noise Amplifier for low-power and narrow-band applications, is investigated and characterized at high temperature. The main figures-of-merit of the designed circuit are extracted and discussed. The good results show that the SOI technology is now emerging as a good candidate for the realization of analog integrated circuits for low-power and high-temperature applications.
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Integration de bobines sur silicium pour la conversion d'energieTROUSSIER, Ghislain 06 July 2004 (has links) (PDF)
Dans un contexte d'integration des dispositifs de conversion d'energie de petite puissance, le travail de these presente porte sur la realisation de micro-bobines integrees sur silicium. Les contraintes liees a ce type d'integration resident dans la mise au point, la compatibilite des procedes technologiques contribuant a la fabrication du systeme complet et le cout de fabrication. Dans un premier temps, une etude bibliographique nous a permis de faire une synthese sur les structures integrables de micro-bobines ainsi que sur les materiaux conducteurs et magnetiques et leurs techniques de depot. Une fois les objectifs fixes, notamment concernant la nature des materiaux a deposer, nous avons mis au point les depots electrochimiques et les procedes photolithographiques de resines epaisses destinees a la realisation de moules. Ces resines doivent resister a la fois a des contraintes chimiques et physiques fortes. Une premiere structure de micro-bobine de type spirale a ete dimensionnee et le processus de fabrication a ete identifie. En parallele, des motifs specifiques de forme bien definie ont ete etudies puis realises afin de caracteriser les couches deposees par electrochimie, en termes de resistivite, permeabilite et composition de l'alliage. La derniere partie de la these a consiste a appliquer ce procede de fabrication a une seconde structure de bobine dont la geometrie a ete definie dans le but de reduire le nombre d'etapes technologiques. Actuellement les premiers prototypes de ces bobines ont ete realises avec de faibles epaisseurs de materiaux. Ceci nous a permis de valider les procedes de fabrication de ces dispositifs.
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Direct dynamic control of impedance for VAR and harmonic compensationPrasai, Anish 11 November 2011 (has links)
Reactive power is critical to reliable operation of the modern AC power system. There is a plethora of motor-loads, transformers, and power-electronic loads connected to the power grid, which consume reactive power for normal operation. Transmission lines also consume reactive power when they are loaded above their surge impedance loading (SIL). Reactive power can exact opportunity cost due to reduced capacity of the lines to carry real power, which in turn lowers revenue. Most transmission owners (TOs) levy large penalties against load serving entities (LSEs), industrial facilities, and other end-use customers, who consume more than their allotted amount, as measured by their power factor. These penalties are to incentivize their customers to meet their reactive power needs locally as well as to recuperate the TOs' financial losses.
Harmonic pollution is another factor that prevents the optimal operation of the grid and the connected loads. Harmonics are attributable to proliferation of the diode-rectifier- or thyristor-rectifier-interfaced loads such as variable speed ac drives and power supplies in server farms, electric arc furnaces, and other non-linear loads, which are widely employed by the industrial sector. With wider adoption of harmonic-rich loads by the consumer sector as well, such as HDTVs and compact fluorescent lamps (CFLs), greater level of triplen harmonics associated with single-phase loads are also increasingly seen on the distribution grid. The increasing penetration of renewable resources and electrification of light-duty vehicles are expected to further aggravate the stresses and congestion on the utility grid.
Reactive power compensation is necessary for supporting the AC grid and maintaining a healthy voltage stability margin. Compensation can also enhance the utilization of system capacity, lower system losses, provide fault ride-through, and enable a quick fault recovery. Existing VAR and harmonic compensation technologies are either too expensive or inadequate to meet the dynamic needs of the modern and the future power system.
This dissertation presents a novel class of Dynamic VAR and Harmonic Compensators (DVHCs) for supplying or absorbing reactive power and providing harmonic filtering, where the compensation is in shunt with the line and the load. The underlying concept is based on augmenting a static or passive component like a capacitor or an inductor with a direct AC converter and imbuing the passive component with dynamic properties. The direct AC converter can be configured as a buck, a boost, or a buck-boost. A `fail-normal' switch is an integral part of the DVHCs that bypasses the converter when it fails, preserving the original functionality and the reliability of the passive component. The DVHCs are modular and scalable such that they can be employed in applications ranging from residential and industrial with voltages less than 480 V, to power distribution level with voltages as high as 35 kV. The Dynamic Inductor (D-IND) and the Dynamic Capacitor (D-CAP) are subclasses of the DVHCs. As the applications for supplying leading VARs are more prevalent, the primary focus of this work is on the buck, the boost, and the buck-boost configurations of the D-CAP.
To understand the characteristics and operation of the DVHCs, this work has developed time-domain models for analyzing the transient and dynamic behavior; frequency-domain models for understanding the harmonic interactions and the steady-state relationships between switch duty and current harmonics; and small-signal models for studying the dynamics of the converter due to various perturbations. The small-signal models also enable extraction of transfer functions in designing controllers and assessing stability margins.
Control architectures and techniques are presented for effectively controlling the D-CAP when commutating the semiconductor devices with both high and low switching frequencies.
In modularly scaling the DVHCs to higher voltages, three medium-voltage topologies are discussed. They are based on series-connecting fractionally-rated devices, AC flying capacitors, and series cascading multiple two-level cells. These implementations allow direct connect to the medium-voltage grid, thereby obviating the use of transformers, and subsequently reducing the losses, cost, complexity, and footprint. A novel AC snubber concept is proposed to provide safe commutation of the AC switches, fault tolerance by managing the energy trapped in parasitics and filters, and to enable dynamic and static voltage sharing when integrated around the series-connected devices.
Design equations for selecting and rating the devices and components in the buck, the boost, and the buck-boost configurations of the D-CAP are presented. Three sets of example designs, with one at low-voltage and two at medium-voltage, are discussed to demonstrate the typical size and ratings of the various components under realistic operating conditions.
Measurements and the related discussions of a 40 kVA buck D-CAP prototype built to validate the effectiveness of the proposed concepts are presented.
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Modelling Of Switched Mode Power Converters : A Bond Graph ApproachUmarikar, Amod Chandrashekhar 08 1900 (has links)
Modelling and simulation are essential ingredients of the analysis and design process in power electronics. It helps a design engineer gain an increased understanding of circuit operation. Accordingly, for a set of specifications given, the designer will choose a particular topology, select component types and values, estimate circuit performance etc. Typically hierarchical modelling, analysis and simulation rather than full detailed
simulation of the system provides a crucial insight and understanding. The combination of
these insights with hardware prototyping and experiments constitutes a powerful and
effective approach to design.
Obtaining the mathematical model of the power electronic systems is a major task before any analysis or synthesis or simulation can be performed. There are circuit oriented simulators which uses inbuilt mathematical models for components. Simulation with equation solver needs mathematical models for simulation which are trimmed according to user requirement. There are various methods in the literature to obtain these mathematical models. However, the issues of multi-domain system modelling and causality of the energy variables are not sufficiently addressed. Further, specifically to power converter systems,
the issue of switching power models with fixed causality is not addressed. Therefore, our research focuses on obtaining solutions to the above using relatively untouched bond graph method to obtain models for power electronic systems. The power electronic system chosen for the present work is Switched Mode Power Converters (SMPC’s) and in particular PWM DC-DC converters.
Bond graph is a labelled and directed graphical representation of physical systems. The basis of bond graph modelling is energy/power flow in a system. As energy or power flow is the underlying principle for bond graph modelling, there is seamless integration across multiple domains. As a consequence, different domains (such as electrical, mechanical, thermal, fluid, magnetic etc.) can be represented in a unified way. The power or the energy
flow is represented by a half arrow, which is called the power bond or the energy bond.
The causality for each bond is a significant issue that is inherently addressed in bond graph modelling. As every bond involves two power variables, the decision of setting the cause variable and the effect variable is by natural laws. This has a significant bearing in the resulting state equations of the system. Proper assignment of power direction resolves the sign-placing problem when connecting sub-model structures. The causality will dictate whether a specific power variable is a cause or the effect. Using causal bars on either ends of the power bond, graphically indicate the causality for every bond. Once the causality gets assigned, bond graph displays the structure of state space equations explicitly.
The first problem we have encountered in modelling power electronic systems with bond graph is power switching. The essential part of any switched power electronic system is a switch. Switching in the power electronic circuits causes change in the structure of the system. This results in change in dynamic equations of the circuit according to position of the switch. We have proposed the switched power junctions (SPJ) to represent switching phenomena in power electronic systems. The switched power junctions are a generalization of the already existing 0-junction and 1-junction concepts of the bond graph element set. The SPJ’s models ideal switching. These elements maintain causality invariance for the whole system for any operational mode of the system. This means that the state vector of the resulting state equation of the system does not change for any operating mode. As SPJs models ideal power switching, the problem of stiff systems and associated numerical stability problems while simulating the system is eliminated. Further, it maintains one to one correspondence with the physical system displaying all the feasible modes of operation at the same time on the same graph.
Using these elements, the switched mode power converters (SMPC's) are modelled in bond graph. Bond graph of the converter is the large signal model of the converter. A graphical procedure is proposed that gives the averaged large signal, steady state and small signal ac models. The procedure is suitable for the converters operating in both Continuous Conduction Mode (CCM) and in Discontinuous Conduction Mode (DCM).
For modelling in DCM, the concept of virtual switch is used to model the converter using bond graph. Using the proposed method, converters of any complexity can be modelled incorporating all the advantages of bond graph modelling.
Magnetic components are essential part of the power electronic systems. Most common parts are the inductor, transformer and coupled inductors which contain both the electric and magnetic domains. Gyrator-Permeance approach is used to model the magnetic components. Gyrator acts as an interface between electric and magnetic domain and capacitor model the permeance of the magnetic circuits. Components like inductor, tapped inductor, transformer, and tapped transformer are modelled. Interleaved converters with coupled inductor, zero ripple phenomena in coupled inductor converters as well as integrated magnetic Cuk converter are also modelled. Modelling of integrated magnetic converters like integrated magnetic forward converter, integrated magnetic boost converter are also explored.
To carry out all the simulations of proposed bond graph models, bond graph toolbox is
developed using MATLAB/SIMULINK. The MATLAB/SIMULINK is chosen since it is general
simulation platform widely available. Therefore all the analysis and simulation can be carried out using facilities available in MATLAB/SIMULINK. Symbolic equation extraction toolbox is also developed which extracts state equations from bond graph model in SIMULINK in symbolic form.
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Alimentation électrique des dispositifs de décharge à barrière diélectrique / Power supplies for dielectric barrier controlled discharges devicesBonnin, Xavier 10 December 2014 (has links)
Les dispositifs DBD se répandent dans un grand nombre d’applications industrielles. Utilisés depuis plus de 150 ans pour la production d’ozone afin de décontaminer l’eau à grande échelle, ils ont depuis la fin du XXème siècle investi les domaines du traitement de surface polymère, du dépôt de couche mince sur substrat et de l’émission lumineuse pour la décontamination ainsi que la médecine. Ces dispositifs sont mis en oeuvre avec un générateur électrique dont les caractéristiques impactent fortement la qualité de la décharge. Ce travail s’inscrit en partie dans le cadre du développement d’une application de traitement de surface à pression atmosphérique. Il aborde la problématique de l’augmentation de la vitesse de dépôt de couche mince au travers des paramètres de l’alimentation électrique. Plus précisément, ce travail s’intéresse aux apports d’une alimentation en courant rectangulaire et aborde également les problématiques liées à la conception et à la fabrication de ce convertisseur. En particulier, une grande attention est portée sur l’étude du transformateur élévateur, car au travers de ses éléments parasites capacitifs, ce dernier peut limiter le transfert de puissance entre la source électrique et le dispositif DBD. Un deuxième aspect de cette étude consiste à entrevoir l’intérêt que revêtent deux convertisseurs statiques dédiés à l’alimentation de dispositifs DBD. Le premier consiste en une alimentation résonante en régime de conduction discontinue dont la particularité est de posséder trois degrés de liberté (fréquence, tension d’entrée et largeur d’impulsion), ce qui lui confère un intérêt exploratoire. Le second convertisseur consiste en une alimentation résonante haute tension et haute fréquence permettant l’éviction du transformateur élévateur, et mettant en oeuvre des interrupteurs au nitrure de gallium (GaN) afin d’atteindre une fréquence de fonctionnement supérieure au mega-Hertz avec un faible niveau de pertes. / DBD devices are widely used in industrial applications. 150 years ago, they were only employed in ozoners for water decontamination. In recent decades, the progress of knowledge and technology allowed to use them in many other applications like surface treatment, medical applications and light emission. Actually, these devices are supplied with an electrical source which parameters can strongly impact the discharge behaviour. An important part of this work comes within the framework of the development of an atmospheric pressure surface treatment involving DBDs. The issue of the influence of the generator's electrical parameters on the treatment speed is discussed. In particular, this work focuses on the merits of a rectangular shaped current source concerning the behavior of an atmospheric pressure discharge in nitrogen ; the problems related to the design and the fabrication of such a converter are highlighted. The design of the high voltage transformer is then described in detail since its lumped elements play an important role as they can strongly limit the power transfer between the electrical source and the DBD device. A second aspect of this work is to establish the interests of two particular power converters. The first one is a resonant converter operating in a discontinuous conduction mode ; its merits is to exhibit three degrees of freedom (input voltage, frequency, current pulse width) instead of two, which is a tremendous asset for exploring purposes. The second one is a high-frequency resonant converter where a resonant inductance and the DBD device structural capacitances are used instead of a high voltage transformer to perform the voltage amplification, which circumvents the issue related to the transformer parasitic elements. This converter is based on GaN HEMT switches in order to reach a low semiconductor losses level and a fairly high operating frequency (above the mega-Hertz).
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Měniče pro svítidla s LED diodami / Inverters for lighting units with LEDsZuber, Zalán January 2010 (has links)
The master‘s thesis deals with DC/DC converters for power LED diodes. Gives an overview of the field of LED lighting technology, analyzes various types of converters and shows their principle of operation. Furthermore presents some possible circuit designs for three different voltage levels and the calculations for each part. As an approval of their functionality the results of their measurements are plotted followed by the data evaluation.
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Implementation of DC-DC converter with maximum power point tracking control for thermoelectric generator applicationsJahanbakhsh, David January 2012 (has links)
A heavy duty vehicle looses approximately 30-40 % of the energy in the fuel as waste heat through the exhaust system. Recovering this waste heat would make the vehicle meet the legislative and market demands of emissions and fuel consumption easier. This recovery is possible by transforming the waste heat to electric power using a thermoelectric generator. However, the thermoelectric generator electric characteristics makes direct usage of it unprotable, thus an electric power conditioner is necessary. First a study of dierent DC-DC converters is presented, based on that the most suitable converter for thermoelectric application is determined. In order to maximize the harvested power, maximum power point tracking algorithms have been studied and analyzed. After the investigation, the single ended primary inductor converter was simulated and implemented with a perturb and observe algorithm, and the incremental conductance algorithm. The converter was tested with a 20 W thermoelectric generator, and evaluated.The results show that the incremental conductance is more robust and stable compared to the perturb and observe algorithm. Further on, the incremental conductance also has a higher average eciency during real implementation.
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High-Precision, Mixed-Signal Mismatch Measurement of Metal-Oxide-Metal Capacitors and a 13-GHz 5-bit 360-Degree Phase ShifterBustamante, Danilo 05 August 2020 (has links)
A high-precision mixed-signal mismatch measurement technique for metal-oxide metal (MoM) capacitors as well as the design of a 13-GHz 5-bit 360-degree phase shifter are presented. This thesis presents a high-precision, mixed-signal mismatch measurement technique for metal-oxide–metal capacitors. The proposed technique incorporates a switched-capacitor op amp within the measurement circuit to significantly improve the measurement precision while relaxing the resolution requirement on the backend analog-to-digital converter (ADC). The proposed technique is also robust against multiple types of errors. A detailed analysis is presented to quantify the sensitivity improvement of the proposed technique over the conventional one. In addition, this thesis proposes a multiplexing technique to measure a large number of capacitors in a single chip and a new layout to improve matching. A prototype fabricated in 180 nm CMOS technology demonstrates the ability to sense capacitor mismatch standard deviation as low as 0.045% with excellent repeatability, all without the need of a high-resolution ADC. The 13-GHz 5-bit 360-degree phase shifter consists of 2 stages. The first stage utilizes a delay line for 4-bit 180-degree phase shift. A second stage provides 1-bit 180-degree phase shift. The phase shifter includes gain tuning so as to allow a gain variation of less than 1 dB. The design has been fabricated in 180 nm CMOS technology and measurement results show a complete 360◦ phase shift with an average step size of 10.7◦ at 13-GHz. After calibration the phase shifter presented an output gain S21 of 0.5 dB with a gain variation of less than 1 dB across all codes at 13-GHz. The remaining s-parameter testing showed a S22 and S11 below -11 dB and a S12 below -49 dB at 13 GHz.
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Conception, réalisation et caractérisation d'inductances et de transformateurs tridimensionnels pour applications RF et microondes / Design, realization and characterization of three-dimensional inductors and transformers for RF (radio frequency) and microwave applicationsBushueva, Olga 07 October 2016 (has links)
La miniaturisation, la fabrication et l'intégration des composants passifs RF constituent des enjeux majeurs actuels, sans oublier le critère du coût de fabrication, très important notamment pour les applications grand public. Les composants passifs tels que les inductances et les transformateurs font l'objet d'un effort de développement permanent pour accroitre leurs performances et réduire la surface occupée. Les travaux décrits dans ce manuscrit s'inscrivent dans ce contexte et visent le développement d'une nouvelle filière technologique permettant la réalisation à faible coût de composants inductifs tridimensionnels à hautes performances. Le travail présenté dans ce mémoire s'articule en quatre chapitres. Le premier chapitre dresse un état de l'art des inductances et des transformateurs intégrés en abordant les principales topologies utilisées, les technologies de fabrication et les applications. Dans le deuxième chapitre, l'étude et l'optimisation des inductances et des transformateurs solénoïdaux est abordée après avoir décrit les origines des pertes limitant les performances. Pour cela, nous avons recours à la simulation électromagnétiques 3D. Dans le troisième chapitre, un problème de caractérisation des composants inductifs à forts coefficients de surtension est soulevé. Après avoir constaté que l'environnement de mesure réduisait artificiellement les performances, quelques solutions sont proposées et vérifiées expérimentalement. Enfin, le dernier chapitre traite de la fabrication et de la caractérisation des composants mis au point. Les meilleures performances mesurées correspondent à un facteur de qualité de 61 à 5,4 GHz pour une inductance de 2,5 nH et un gain maximum disponible de -0,5 dB à -0,39 dB sur la plage 3,8 - 6,5 GHz pour un transformateur 2:2. Ces résultats placent ces composants parmi les meilleures réalisations actuelles. / The miniaturization, fabrication and integration of RF passive components are current major challenges, also taking into account the fabrication cost which is very important especially for consumer applications. Passive components such as inductors and transformers are subject to an ongoing development to improve their performance and reduce the area occupied. The work described in this manuscript is part of that context and target the development of a new technological process allowing the production of low-cost three-dimensional high-performance inductive components. The work presented in this paper is divided into four chapters. The first chapter describes the state of the art of integrated inductors and transformers by addressing the main topologies used fabrication technologies and applications. In the second chapter, the study and optimization of solenoid inductors and transformers is discussed after describing the origins of performance limiting losses. For this, we use the 3D electromagnetic simulation. In the third chapter, the problem concerning the characterization of inductive components with high Q factor is raised. After finding that the measurement environment artificially reduces performance, some solutions are proposed and experimentally verified. Finally, the last chapter discusses the fabrication and characterization of developed components. The best measured performance corresponds to a quality factor of 61 to 5.4 GHz for an inductance value of 2.5 nH and a maximum available gain of -0.5 dB to 0.39 dB over the range from 3.8 to 6.5 GHz for a 2:2 transformer. These results place these components among the best current achievements.
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