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A PLL Design Based on a Standing Wave Resonant OscillatorKarkala, Vinay 2010 August 1900 (has links)
In this thesis, we present a new continuously variable high frequency standing wave oscillator
and demonstrate its use in generating the phase locked clock signal of a digital IC.
The ring based standing wave resonant oscillator is implemented with a plurality of wires
connected in a mobius configuration, with a cross coupled inverter pair connected across
the wires. The oscillation frequency can be modulated by coarse and fine tuning. Coarse
modification is achieved by altering the number of wires in the ring that participate in the
oscillation, by driving a digital word to a set of passgates which are connected to each wire
in the ring. Fine tuning of the oscillation frequency is achieved by varying the body bias
voltage of both the PMOS transistors in the cross coupled inverter pair which sustains the
oscillations in the resonant ring. We validated our PLL design in a 90nm process technology.
3D parasitic RLCs for our oscillator ring were extracted with skin effect accounted for.
Our PLL provides a frequency locking range from 6 GHz to 9 GHz, with a center frequency
of 7.5 GHz. The oscillator alone consumes about 25 mW of power, and the complete PLL
consumes a power of 28.5 mW. The observed jitter of the PLL is 2.56 percent. These numbers
are significant improvements over the prior art in standing wave based PLLs.
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PLL (Phase-Locked Loop) structures for single phase and three phase systems with a high rejection capacity to sub and interharmonic / Estruturas de PLL (Phase-Locked Loop) monofÃsica e trifÃsica com alta rejeiÃÃo a sub e inter-harmÃnicasRenato Guerreiro AraÃjo 18 November 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / In applications related to power converters, such as inverters, rectifiers and the use of active filters, the synchronization method represent a very important element in the performance of the control strategy of this equipment. The estimated values of the synchronism angle, frequency and amplitude determined by the synchronization algorithms present, facing strongly distorted signals with the presence of sub and interharmonics, high errors. This study presents two algorithms: one applied on single-phase electrical systems and one applied on three-phase electrical systems, with high immunity to interharmonics and subharmonics. First are presented the main synchronization systems that are used in the electrical power systems. In addition, will be presented the main causes and consequences of the presence of subharmonics and interharmnics in the system, as well as the mathematical modeling of the two algorithms with high rejection to these disturbances. Will be presented the simulation and the experimental results of the proposed algorithms and the comparison between these synchronization methods with particular methods present in the literature. As a result of the study, it can be seen that the proposed structures present a higher response time, but the error of the estimated signal with respect the fundamental component of the input signal is lower when compared to structures such as EPLL and structures based on SOGI. It was observed that the proposed synchronization methods are enabled to estimate the synchronism angle, the frequency and the fundamental component of the input signal adequately and can be used in control strategies of power converters. / Em aplicaÃÃes relacionadas à EletrÃnica de PotÃncia, como inversores, retificadores e a utilizaÃÃo de filtros ativos, o mÃtodo de sincronizaÃÃo representa um elemento chave no desempenho da estratÃgia de controle destes equipamentos. Os valores do Ãngulo de sincronismo, frequÃncia e amplitude estimados com determinados algoritmos de sincronizaÃÃo apresentam, diante de sinais fortemente distorcidos com a presenÃa de sub e inter-harmÃnicos, erros elevados. Neste trabalho sÃo apresentados dois algoritmos: um aplicado a sistemas elÃtricos monofÃsicos e outro aplicado a sistemas elÃtricos trifÃsicos, com elevada imunidade a inter-harmÃnicos e sub-harmÃnicos. Primeiramente sÃo apresentados os principais sistemas de sincronizaÃÃo utilizados em sistemas elÃtricos de potÃncia. AlÃm disso, sÃo apresentadas as principais causas e consequÃncias da presenÃa de sub-harmÃnicos e inter-harmÃnicos no sistema, bem como a modelagem matemÃtica dos dois algoritmos com elevada rejeiÃÃo a estes distÃrbios. SÃo apresentados os resultados de simulaÃÃo e experimentais dos algoritmos propostos e a comparaÃÃo entre estes mÃtodos de sincronizaÃÃo com determinados mÃtodos presentes na literatura. Como resultado do estudo, pode-se observar que as estruturas de sincronizaÃÃo propostas apresentam um tempo de resposta mais elevado, porÃm o erro do sinal estimado em relaÃÃo a componente fundamental do sinal de entrada à inferior quando comparado a estruturas como o EPLL e estruturas baseadas no SOGI. Com isso, tem-se que as mesmas estÃo habilitadas para estimar o Ãngulo de sincronismo, a frequÃncia e a componente fundamental do sinal de entrada adequadamente e podem serem utilizadas eficientemente em estratÃgias de controle de conversores de potÃncia.
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Um estudo sobre o desempenho de algoritmos de estimação de frequência visando unidades de medição fasorialSouza, José Renato Cozzolino Rodrigues de 03 July 2017 (has links)
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José Renato Cozzolino.pdf: 2923143 bytes, checksum: 2941736082bf50938fdb3dcfea03c36e (MD5) / A estimação correta de frequência é essencial para a operação de diversos equipamentos de proteção, regulação e controle, os quais são necessários para operação adequada do Sistema Interligado Nacional A tecnologia de Sistemas de Medição Fasorial Sincronizada (Synchronized Phasor Measurement Systems - SPMS), baseia-se em uma rede de Unidades de Medição Fasorial (Phase Measurement Unit - PMU). Duas grandezas importantes medidas pela PMUs são a frequência e a taxa de variação da frequência. Este trabalho apresenta o resultado de estudo comparativo de algoritmos de estimação de frequência no âmbito de medição fasorial sincronizada. Foram avaliados os modelos propostos originalmente pela Norma IEEE C37.118, por seu documento de alteração ( IEEE Std. C37.118.1a-2014 Amendment), alem de três diferentes tipos de algoritmos baseados em PLLs (Phasor Locked Loop). As avaliações foram executadas com base nos testes descritos na Norma IEEE C37.118 e seus respectivos requisitos de conformidade. Verificou-se que as modificações apresentadas pelo documento Amendment foram necessárias para que o modelo de PMU proposto atendesse os requisto para todos os testes. Em relação aos modelos de PLL, verificou-se que uma versão do algoritmo (chamada aqui de PLL de Classe III) foi bem superior às demais e também melhor que o algoritmo sugerido pelo Amendment no que se refere ao teste de derivada da frequência e de modulação de fase. / An accurate frequency estimation is essential for the operation of Electric Power System regarding protection and control. Synchronized Phasor Measurement Systems - SPMS are based on a network composed by Phasor Measurement Units (Phase Measurement Unit - PMU). Two important parameters measured by the PMUs are the frequency and the frequency rate of change. This paper presents the results of a comparative study of frequency estimation algorithms within synchronized phasor measurement context. The reference model proposed in by IEEE C37.118 standard was compared with three different algorithms based on PLLs (Phasor Locked Loop). The evaluations were performed based on the compliance requirements described in IEEE C37.118. It was also found that the PLLs models have superior performance than model reference for P PMU suggested by Standard. Regarding the reference model for PMU M, there is a need to implement anti-aliasing filters for the standard inter-harmonics tests. After that, it was observed that the dynamic performances of PLLs studied at work are compatible with the algorithms suggested by the standard for the PMU M.
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Modélisation électrique de laser semi-conducteurs pour les communications à haut débit de données / Electrical modeling of semiconductor laser for high data rate communicationKassa, Wosen Eshetu 12 May 2015 (has links)
L'avancement de la communication numérique optique dans les réseaux longue distance et d'accès a déclenché les technologies émergentes dans le domaine micro-ondes / ondes millimétriques. Ces systèmes hybrides sont fortement influencés non seulement par les déficiences de liens optiques mais aussi des effets de circuits électriques. Les effets optiques et électriques peuvent être ainsi étudiés en même temps en utilisant des outils assistés par ordinateur en développant des modèles de circuit équivalent de l'ensemble des composants de liaison tels que les lasers à semi-conducteurs, modulateurs, photo-détecteurs et fibre optique. Dans cette thèse, les représentations de circuit des composants de liaison photoniques sont développées pour étudier des architectures différentes. Depuis la source de lumière optique est le principal facteur limitant de la liaison optique, une attention particulière est accordée aux caractéristiques, y compris les plus importants de simples lasers en mode semi-conducteurs. Le modèle de circuit équivalent de laser qui représente l'enveloppe du signal optique est modifié pour inclure les propriétés de bruit de phase du laser. Cette modification est particulièrement nécessaire d'étudier les systèmes où le bruit de phase optique est important. Ces systèmes comprennent des systèmes de télécommande hétérodynes optiques et des systèmes auto-hétérodynes optiques. Les résultats de mesure des caractéristiques de laser sont comparés aux résultats de simulation afin de valider le modèle de circuit équivalent dans des conditions différentes. Il est démontré que le modèle de circuit équivalent peut prédire avec précision les comportements des composants pour les simulations au niveau du système. Pour démontrer la capacité du modèle de circuit équivalent de la liaison photonique pour analyser les systèmes micro-ondes / ondes millimétriques, le nouveau modèle de circuit du laser avec les modèles comportementaux des autres composants sont utilisés pour caractériser différents radio sur fibre (RoF) liens tels que la modulation d'intensité - détection directe (IM-DD) et les systèmes RoF hétérodynes optique. Signal sans fil avec des spécifications conformes à la norme de IEEE 802.15.3c pour la bande de fréquence à ondes millimétriques est transmis sur les liens RoF. La performance du système est analysée sur la base de l'évaluation de l'EVM. L'analyse montre que l'analyse efficace des systèmes de photonique micro-ondes / ondes millimétriques est obtenue en utilisant des modèles de circuit qui nous permet de prendre en compte les comportements à la fois électriques et optiques en même temps / The advancement of digital optical communication in the long-haul and access networks has triggered emerging technologies in the microwave/millimeter-wave domain. These hybrid systems are highly influenced not only by the optical link impairments but also electrical circuit effects. The optical and electrical effects can be well studied at the same time using computer aided tools by developing equivalent circuit models of the whole link components such as semiconductor lasers, modulators, photo detectors and optical fiber. In this thesis, circuit representations of the photonic link components are developed to study different architectures. Since the optical light source is the main limiting factor of the optical link, particular attention is given to including the most important characteristics of single mode semiconductor lasers. The laser equivalent circuit model which represents the envelope of the optical signal is modified to include the laser phase noise properties. This modification is particularly necessary to study systems where the optical phase noise is important. Such systems include optical remote heterodyne systems and optical self-heterodyne systems. Measurement results of the laser characteristics are compared with simulation results in order to validate the equivalent circuit model under different conditions. It is shown that the equivalent circuit model can precisely predict the component behaviors for system level simulations. To demonstrate the capability of the equivalent circuit model of the photonic link to analyze microwave/millimeter-wave systems, the new circuit model of the laser along with the behavioral models of other components are used to characterize different radio-over-fiber (RoF) links such as intensity modulation – direct detection (IM-DD) and optical heterodyne RoF systems. Wireless signal with specifications complying with IEEE 802.15.3c standard for the millimeter-wave frequency band is transmitted over the RoF links. The system performance is analyzed based on EVM evaluation. The analysis shows that effective analysis of microwave/millimeter-wave photonics systems is achieved by using circuit models which allows us to take into account both electrical and optical behaviors at the same time
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Model trojfázové umělé sítě / Model of Three-phase Power MicrogridMacík, Tomáš January 2020 (has links)
The Diploma thesis deals with control of three-phase active rectifier and a three-phase DC/AC converter. It also explains phase-locked loop principle. The theoretical part including first three chapters lists several control approaches to three phase active rectifier and three phase DC/AC converter. Described control approaches to the active rectifier are control in dq frame and control in dq UVW frame. Listed control approaches to the DC/AC converter include cascaded control structure and a full state feedback control. The practical part is divided into last three chapters and includes mathematical description of phase-locked loop principle, model of active rectifier controlled in dq frame and a model of DC/AC converter controlled both by a cascaded control and a full¬ state feedback. The models are created in Matlab Simulink.
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Měření průtoku plynů / Gas flow measurementKozák, Matěj January 2011 (has links)
This thesis deals with the problem of designing vortex flow meter for a nominal range of 40 l.min-1. It describes the problems of vortex bodies and choice of methods for detection of vortices. The thesis includes solution of various problems in the design, which were published in scientific articles or patents. The following describes the design solution vortex flow meter for the specified range, which uses ultrasonic sensors to vortices detection. The proposed flow meter is calibrated with reference flow meter and compared with commercially produced vortex flow by the TST electronics and Burkert companies, which are designed for the specified ranges.
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Synchronizované zdroje časových signálů / Synchronized sources of clock signalsFlorián, Antonín January 2013 (has links)
This thesis deals with design of synchronized sources of time signal. The first part of the thesis deals with the theory the crystal resonators, crystal oscillators and PLL. The second part of the thesis deals with the crystal oscillator with 10MHz frequency. In the oscillator is use of SC cut crystal. The third part of the work deals with method of synchronization. To synchronization is use of PLL.
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Měřicí zesilovač využívající vektorové synchronní detekce / Vector phase-sensitive measurement amplifierRejnuš, Milan January 2014 (has links)
The master’s thesis describes known methods of signal measurement using principle of synchronous detection. Various methods are presented, their principles are examined and the problems when using them are analyzed. Further, procedures for reduction of adverse effects are described also. Second part of this thesis is focused on the instrument design. The instrument is intended for detection and processing of the output signals in a given optometric system. The proposed device is designed to operate on the principle of synchronous detection method using a vector signal evaluation. Advantages and disadvantages are discussed below.
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Quantization Effects Analysis on Phase Noise and Implementation of ALL Digital Phase Locked-LoopShen, Jue January 2011 (has links)
With the advancement of CMOS process and fabrication, it has been a trend to maximize digital design while minimize analog correspondents in mixed-signal system designs. So is the case for PLL. PLL has always been a traditional mixed-signal system limited by analog part performance. Around 2000, there emerged ADPLL of which all the blocks besides oscillator are implemented in digital circuits. There have been successful examples in application of Bluetooth, and it is moving to improve results for application of WiMax and ad-hoc frequency hopping communication link. Based on the theoretic and measurement results of existing materials, ADPLL has shown advantages such as fast time-to-market, low area, low cost and better system integration; but it also showed disadvantages in frequency resolution and phase noise, etc. Also this new topic still opens questions in many researching points important to PLL such as tracking behavior and quantization effect. In this thesis, a non-linear phase domain model for all digital phase-locked loop (ADPLL) was established and validated. Based on that, we analyzed that ADPLL phase noise prediction derived from traditional linear quantization model became inaccurate in non-linear cases because its probability density of quantization error did not meet the premise assumption of linear model. The phenomena of bandwidth expansion and in-band phase noise decreasing peculiar to integer-N ADPLL were demonstrated and explained by matlab and verilog behavior level simulation test bench. The expression of threshold quantization step was defined and derived as the method to distinguish whether an integer-N ADPLL was in non-linear cases or not, and the results conformed to those of matlab simulation. A simplified approximation model for non-linear integer-N ADPLL with noise sources was established to predict in-band phase noise, and the trends of the results conformed to those of matlab simulation. Other basic analysis serving for the conclusions above covered: ADPLL loop dynamics, traditional linear theory and its quantitative limitations and numerical analysis of random number. Finally, a present measurement setup was demonstrated and the results were analyzed for future work.
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A Study of Injection Locking in Optoelectronic OscillatorPrakasha, Prarthana 30 September 2020 (has links)
The random fluctuations of signal phase of an oscillator limit the precision of time and frequency measurements. The noise and long-term stability of the system’s oscillator or clock is of major importance in applications such as optical and wireless communications, high-speed digital electronics, radar, and astronomy. The Optoelectronic Oscillator (OE Oscillator), a new class of time delay oscillator with promise as a low-phase noise source of microwave carriers, was introduced by Steve Yao and Lute Malek in 1996. The OE Oscillator combines into a closed loop an RF photonic link and an RF chain. The RF photonic link consists of a laser, electro-optic modulator, optical fibre delay line, and a photo-receiver that together provide an RF delay. An RF chain consists of one or more amplifiers and a RF resonator that together provide the sustaining amplification and the frequency selectivity necessary for single mode oscillation of the loop. The low loss of optical fibres enables the attainment of delays that correspond to optical fibre lengths of several kilometers. It is the long delay, unattainable in an all electronic implementations that is responsible for the superior phase noise performance of an OE Oscillator.
In this thesis the fundamental principles of operation of an OE Oscillator are described and the principal sources of in-loop phase fluctuations that are responsible for phase-noise identified. This lays the ground for an exposition of the mechanism that describes the perturbation of a time delay oscillator by injection into the loop of a carrier that is detuned in frequency from the natural frequency of the oscillator. For sufficiently small detuning the oscillator can become phase locked to the injected carrier. The model presented in the thesis generalises the traditional Yao-Maleki and Leeson model to include all the important features that describe the injection locking dynamics of an OE Oscillator. In particular the common assumptions of single mode oscillation and weak injection are removed. This is important to correctly predict the effect of injection locking on the spurious peaks in the phase noise spectrum corresponding to the side-modes of a time delay oscillator. Simulation results are presented in order to validate the dynamics of the oscillator under injection and analytic results on the lock-in range and phase noise spectrum. A 10 GHz OE Oscillator with a single 5km delay line is used as an example in the simulation illustration.
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