<p>Fans are often used in equipment such as home appliances andelectronic equipment where the margin of profit is small butcustomers demands on a low noise level are high. Therefore,methods for predicting the noise emitted by an applicationincluding one or several fans are desirable in order toimprove, accelerate and reduce the cost of low-noise design.The Noise Shaping Technology (NST) has been developed withinthe EC-project NABUCCO in order to fulfil the aboverequirements on a prediction method. According to NST, thenoise source (not necessary a fan) is described by one orseveral noise descriptors, CSSs, and the correspondingtransmission paths through the structure described by one orseveral transfer functions, ACFs. In this thesis, theapplicability of NST is evaluated on a cabinet for electronicequipment where small axial cooling fans constitute the primarysources of the airborne sound.</p><p>As an axial fan is a complex source of sound,simplifications are necessary when modelling its acousticproperties. Therefore, the sound radiation of an axial fan infree space was examined by expanding the generated soundpressure field into spherical harmonics. The conclusion on asource model for the cabinet example, where the fans are moreor less In-duct mounted, is a modified single axial dipole. Themodel is expected to be valid in the entire frequency range ofinterest except in the mid-frequency range where the modaldensity is low. In order to improve the source model in thisfrequency range, a future model based on a rotating dipole isproposed.</p><p>The sound power of a small axial fan is measured in an ISO10302 test-rig. In order to take account of flow conditions,acoustically transparent ducts have been developed. These shallbe attached to the test-rig when measuring the sound power ofthe fan. A simple but practical method of how to correct thesound power for the baffling effect of the test-rig has alsobeen developed. Finally, the sound power can be converted intodipole force, which is the airborne CSS corresponding to thesingle axial dipole model.</p><p>The corresponding airborne transfer function (ACF), i.e.,from dipole force at the source point to sound pressure at thereceiver point, is measured reciprocally by taking use ofLyamshevs reciprocity relation.</p><p>From multiplication of the CSS and the ACF, the soundpressure can be predicted. The prediction shows quite goodagreement with the measured values.</p><p><b>Keywords:</b>axial fan, airborne sound, sourcecharacterisation, transmission path analysis, In-duct,spherical harmonics, rotating dipole, installation effects, ISO10302, flow conditions, baffling effect, acousticallytransparent ducts, Lyamshevs reciprocity relation, reciprocity,CSS, ACF, GSM, NST.</p>

Great portion of today's industry are <em>Adjustable Speed Drives</em> (<em>ASD's</em>) operated in order to fulfill certain processes. When these processes are critical ones or sensitive to voltage disturbances, that might take place due to inserting high load in an area near to the Point of Common Coupling (<em>PCC</em>) of the process or due to a short term outage, few tens of thousands up to millions of dollars will be lost once such interruptions (voltage sags) take place as a result of the process failure. On the other hand, a distorted voltage waveform at the PCC for some sensitive process might malfunction as a result of the high harmonic content of the voltage waveform. Utilities are required to deliver as pure as possible sinusoidal voltage waveform according to certain limits; thus, they might apply fines against the consumers who are responsible for producing high amounts of current harmonics that affect the voltage wave shape at the <em>PCC</em> in order to force them to improve the consumer's load profile by adding filters at <em>PCC</em> for instance. Utilities are charging the consumers who are drawing power at poor power factor as well. <br /><br /> This thesis presents an <em>ASD</em> retrofitted with a dual-functional piece of hardware connected in series to its <em>DC-link</em> that is capable of handling the previously two mentioned problems. In other words, hardware that is capable of providing <em>voltage sag ride-through</em> during the voltage sag conditions on one side, on the other side, during the normal operating conditions, it is capable to mitigate the harmonic contents of the drawn current by the ASD's rectifier and to improve the power factor. <br /><br /> Survey on voltage sag ride-through for ASD's approaches are presented in the literature has been made. Approaches are classified as the topology utilized; first, topologies that utilizes energy storage elements that store energy to compensate the DC-link voltage with during the voltage sags, second, topologies retrofitting the DC-link itself with additional hardware to compensate the DC-link voltage. The first group is capable to provide voltage compensating during the full outages while the second can't. The presented voltage sag ride-through work of this thesis belongs to the second group. <br /><br /> Boost converter has been used as the hardware to compensate the DC-link voltage because of its simplicity and cheap price. An adaptive linear network (ADALINE) is investigated as the detection system to detect the envelope of the input voltage waveform. Once the envelope of the voltage goes below a certain level, the boost converter is activated to compensate the difference between voltage set point and the actual DC-link voltage. Simulation results supporting the proposed configuration are presented. <br /><br /> A third-harmonic current injection approach is utilized in this work in order to achieve <em>total harmonic distortion</em> (<em>THD</em>) mitigation from 32% to 5. 125% (theoretically). Two third-harmonic current injection networks have been investigated; one utilizes a real resistor, the other utilizes a resistor emulator to reduce the energy dissipated. The proposed controller for the resistor emulator does not require a proportional-integral (PI) controller. <br /><br /> As a result of the common devices between the voltage sag ride-through circuitry and the harmonic mitigation one, they can be integrated together in one circuitry connected in series with the DC-link of the ASD. And hence, the dual functionality of the hardware will be achieved. Simulation results supporting the theoretical results have been presented.

<p>Naučna rasprava izložena u ovoj tezi bavi se analizom<br />kvaliteta električne energije. Visok nivo električne<br />energije podrazumeva da su napon napajanja i struja<br />potrošača idealne sinusoide sa tačno određenom<br />amplitudom i učestanošću. Bilo kakva odstupanja od<br />idealnog nazivaju se izobličenja i najčešće se<br />karakterišu sa harmonicima.<br />Poslednjih godina dolazi do naglog razvoja<br />poluprovodničkih komponenata. Takve komponente su<br />uticale na ubrzan razvoj snažnih uređaja energetske<br />elektronike. Ti uređaji su nelinearnog karaktera, što<br />dovodi do pojave harmonika u signalima napona i struja<br />elektroenergetskog sistema. Prvi problem kojim se bavi<br />ova teza je analiza talasnih oblika struja ispravljača.<br />Metode primenjene za analizu su wavelet transformacija<br />(VT) i modulated overlapped transformacija (MLT). MLT<br />nadoknađuje nedostatak VT da dekomponuje signal u<br />odgovarajuće podopsege koji mogu sadržati i više<br />harmonika i daje tačnu informaciju o svakom harmoniku.<br />Obe metode su pogodne za offline analizu. Za online analizu<br />predložen je hibridni metod baziran na diskretnoj<br />Furijeovoj transformaciji (DFT) i adaptivnom pojasnom<br />filteru (EPLL). Hibridni metod je zadržao dinamički<br />odziv DFT-a, dok je EPLL obezbedio sinhronizaciju sa<br />osnovnom učestanošću sistema. Hibridni metod daje<br />dovoljno tačnu informaciju o osnovnom i višim<br />harmonicima samo ako su njihove učestanosti ceolobrojni<br />umnožak učestanosti osnovnog harmonika. U slučaju pojave<br />interharmonika, odnosno kada taj odnos više ne važi,<br />hibridni metod ne daje tačne rezultate. Za analizu takvih<br />signala predložen je novi metod, koji je baziran na<br />adaptivnom diskretnom pojasnom filteru (ANF) t.j. metod<br />koristi diskretni pojasni filter za modelovanje<br />harmonijskih komponenata u ulaznom signalu, dok se<br />prošireni Kalmanov filter (EKF) koristi kao adaptivni<br />mehanizam. Novi metod je preuzeo osobinu ANF-a da može<br />adaptivno da prati promene učestanosti i osobinu EKF-a<br />da ima bolji dinamički odziv. Metode su implementirane<br />na digitalnom procesoru za obradu signala i upoređene sa<br />postojećim metodama. Metode pokazuju prednosti u odnosu<br />na druge metode.</p> / <p>Scientific research in this thesis discusses power quality<br />analysis. High power quality assumes that both the voltage<br />power supply and the load current are ideal sinusoidal signals<br />with a precisely defined amplitude and frequency. Any<br />deviations from this ideal vaweform are considered as distortion<br />and are characterised by harmonics.<br />Over the last few decades, there has been a rapid development<br />of semiconductor components. Such components made an<br />impact on the fast development of power electronics devices.<br />These devices are nonlinear, introducing harmonics in both<br />voltage and current of the power grid. The first issue researched<br />in this thesis is the analysis of the rectifier voltage and current<br />waveforms. Methods used for the analysis are the wavelet<br />transform (WT) and the modulated overlapped transform (MLT).<br />The MLT overcomes the drawback of the WT, which<br />decomposes the signal into subbands that can contain more<br />harmonics, and gives accurate information about every<br />harmonic. Both methods are suitable for offline analysis. For<br />online analysis, a hybrid method is proposed, based on the<br />discrete Fourier transform (DFT) and the adaptive notch filter<br />(EPLL). The hybrid method retains a good dynamic response of<br />the DFT whereas the EPLL provides a synchronisation with the<br />fundamental system frequency. The hybrid method provides<br />accurate information on the fundamental and the higher<br />harmonics only if their frequencies are integer multiples of the<br />fundamental frequency. In the case of interharmonics, i.e. when<br />this integer ratio is not valid, the hybrid method does not provide<br />accurate results. In order to analyse such signals, a new<br />method is proposed. It is based on discrete adaptive notch filter<br />(ANF), i.e. the method uses a discrete notch filter for modeling<br />the harmonic components in the input signal, whereas an<br />Extended Kalman Filter (EKF) is used as an adaptation<br />algorithm. The adaptive notch Kalman filter inherited the<br />property of the ANF to adaptively track changes in the<br />frequency and the property of the EKF to have a faster dynamic<br />response. Methods have been implemented in a digital signal<br />processor and compared with the existing ones. The methods<br />show advantages compared to other methods.</p>

This study examines the five late keyboard works of Cesar Franck: the Prelude, Chorale, and Fugue and the Prelude. Aria, and Finale for piano, and the three organ chorales. The study focuses on harmonic and contrapuntal techniques and their interrelationships, placing the discussion in the context of an analysis of the whole piece. The primary goal is to identify the salient characteristics of each piece; a secondary goal is to identify common harmonic and contrapuntal aspects of Franck's style.

The electricity network is undergoing significant changes in the transition to a low carbon system. The growth of renewable distributed generation (DG) creates a number of technical and economic challenges in the electricity network. While the development of the smart grid promises alternative ways to manage network constraints, their impact on the ability of the network to accommodate DG – the ‘hosting capacity’- is not fully understood. It is of significance for both DNOs and DGs developers to quantify the hosting capacity according to given technical or commercial objectives while subject to a set of predefined limits. The combinational nature of the hosting capacity problem, together with the intermittent nature of renewable generation and the complex actions of smart control systems, means evaluation of hosting capacity requires appropriate optimisation techniques. This thesis extends the knowledge of hosting capacity. Three specific but related areas are examined to fill the gaps identified in existing knowledge. New evaluation methods are developed that allow the study of hosting capacity (1) under different curtailment priority rules, (2) with harmonic distortion limits, and (3) alongside energy storage systems. These works together improve DG planning in two directions: demonstrating the benefit provided by a range of smart grid solutions; and evaluating extensive impacts to ensure compliance with all relevant planning standards and grid codes. As an outcome, the methods developed can help both DNOs and DG developers make sound and practical decisions, facilitating the integration of renewable DG in a more cost-effective way.

The purpose of this study is to determine a model for analysis of integrating solar generation to the electric grid .The model is then used in determining Harmonics of Integrating solar panels to the electric grid that are based on parallel or series combination of solar cells. To study integration of solar generation to the grid, we have used solar series and solar parallel models in EMTP (Electro Magnetic Transient Program) real time simulation software. When integrating solar generation models to the grid, due to DC to AC conversion and due to variation of solar energy intensity, the electric utility shall experience undesired harmonics that may impact quality of service to other customers in the grid. This study identifies one method of analysis for determining harmonic content of solar panels before solar generation can be integrated in to the electric grid.

Este trabalho aborda a conformidade dos medidores de energia em sistemas não senoidais, na busca do aumento de qualidade no faturamento de energia elétrica. Para tanto, enfoca a medição mais justa e um melhor relacionamento entre concessionária e consumidor. As análises foram realizadas nos laboratórios da Eletropaulo, do Instituto de Eletrotécnica e Energia da Universidade de São Paulo, e no Laboratório do Centro de Estudos em Regulação e Qualidade de Energia (Enerq), USP. Trata-se de um estudo que faz parte de um projeto maior de Pesquisa e Desenvolvimento da Agência Nacional de Energia Elétrica (ANEEL). Seu objetivo foi investigar se a distorção de tensão e corrente nos medidores de faturamento de energia elétrica provoca desvios na energia medida. Pretendeu-se ainda avaliar se as harmônicas inseridas nos medidores eletromecânicos possuem maior ou menor desvio na energia medida, em comparação aos medidores eletrônicos. A metodologia utilizada incluiu levantamento de estudos de pesquisa e desenvolvimento, além de ensaios de laboratório com amostras de equipamentos de dois fabricantes nacionais. Como parâmetros para os ensaios, levantaram-se curvas, por meio de medições de cargas reais. Os resultados das medições obtidas em situações reais foram comparados com aquelas levantadas nos laboratórios. Os resultados dos ensaios laboratoriais foram analisados e comparados com os limites estabelecidos nas normas vigentes, dentre as quais, destacam-se: o Regulamento Técnico Metrológico do INMETRO e os Procedimentos de Distribuição de Energia Elétrica no Sistema Elétrico Nacional PRODIST. O presente estudo concluiu que os instrumentos ensaiados em conforme normas, quando parametrizados para não considerar a potência de distorção no cálculo de reativo, atendem os parâmetros de exatidão. Esses dados são válidos tanto para as funções de VArh quanto para Wh. / This work addresses the reliability of energy meters in nonsinusoidal systems, looking for the increase of quality in the electric energy billing. To that purpose, it focuses on a fairer metering and a better relationship between the concessionaire and consumer. The tests were carried through in the laboratories of Eletropaulo, of the Electro-Technology and Energy Institute in the University of São Paulo, and in the Laboratory of the Center of Studies in Power Quality Regulation (Enerq), USP. This study is part of a bigger project in Research and Development of the Electric Energy National Agency (Aneel). Its objective was to investigate whether the distortion of voltage and current in the electric energy billing meters had deviations in the metered energy. It was also intended to evaluate whether the inserted harmonics in the electromechanical meters have greater or minor deviation in the metered energy, in comparison to the electronic meters. The methodology used included a survey of studies, research and development of the electric sector, besides laboratory tests with two national equipment samples. As parameters for the tests, wave were formulated by means of real load metering. The results of the metering obtained in real situations were compared with those collected in the laboratories. The results of the laboratory tests were analyzed and compared with the limits established in the norms in force, amongst which one highlights: the Technical Metrological Regulation from Inmetro and the Electric Power Distribution Procedures in the National Electric System Prodist. The present study concluded the instruments analyzed under normalized conditions, when parameterized to not consider the distortion power in the calculation of reactive, meet the 60Hz frequency, within the accuracy parameters. These data are valid both for the VArh functions and the Wh.

Este trabalho aborda a conformidade dos medidores de energia em sistemas não senoidais, na busca do aumento de qualidade no faturamento de energia elétrica. Para tanto, enfoca a medição mais justa e um melhor relacionamento entre concessionária e consumidor. As análises foram realizadas nos laboratórios da Eletropaulo, do Instituto de Eletrotécnica e Energia da Universidade de São Paulo, e no Laboratório do Centro de Estudos em Regulação e Qualidade de Energia (Enerq), USP. Trata-se de um estudo que faz parte de um projeto maior de Pesquisa e Desenvolvimento da Agência Nacional de Energia Elétrica (ANEEL). Seu objetivo foi investigar se a distorção de tensão e corrente nos medidores de faturamento de energia elétrica provoca desvios na energia medida. Pretendeu-se ainda avaliar se as harmônicas inseridas nos medidores eletromecânicos possuem maior ou menor desvio na energia medida, em comparação aos medidores eletrônicos. A metodologia utilizada incluiu levantamento de estudos de pesquisa e desenvolvimento, além de ensaios de laboratório com amostras de equipamentos de dois fabricantes nacionais. Como parâmetros para os ensaios, levantaram-se curvas, por meio de medições de cargas reais. Os resultados das medições obtidas em situações reais foram comparados com aquelas levantadas nos laboratórios. Os resultados dos ensaios laboratoriais foram analisados e comparados com os limites estabelecidos nas normas vigentes, dentre as quais, destacam-se: o Regulamento Técnico Metrológico do INMETRO e os Procedimentos de Distribuição de Energia Elétrica no Sistema Elétrico Nacional PRODIST. O presente estudo concluiu que os instrumentos ensaiados em conforme normas, quando parametrizados para não considerar a potência de distorção no cálculo de reativo, atendem os parâmetros de exatidão. Esses dados são válidos tanto para as funções de VArh quanto para Wh. / This work addresses the reliability of energy meters in nonsinusoidal systems, looking for the increase of quality in the electric energy billing. To that purpose, it focuses on a fairer metering and a better relationship between the concessionaire and consumer. The tests were carried through in the laboratories of Eletropaulo, of the Electro-Technology and Energy Institute in the University of São Paulo, and in the Laboratory of the Center of Studies in Power Quality Regulation (Enerq), USP. This study is part of a bigger project in Research and Development of the Electric Energy National Agency (Aneel). Its objective was to investigate whether the distortion of voltage and current in the electric energy billing meters had deviations in the metered energy. It was also intended to evaluate whether the inserted harmonics in the electromechanical meters have greater or minor deviation in the metered energy, in comparison to the electronic meters. The methodology used included a survey of studies, research and development of the electric sector, besides laboratory tests with two national equipment samples. As parameters for the tests, wave were formulated by means of real load metering. The results of the metering obtained in real situations were compared with those collected in the laboratories. The results of the laboratory tests were analyzed and compared with the limits established in the norms in force, amongst which one highlights: the Technical Metrological Regulation from Inmetro and the Electric Power Distribution Procedures in the National Electric System Prodist. The present study concluded the instruments analyzed under normalized conditions, when parameterized to not consider the distortion power in the calculation of reactive, meet the 60Hz frequency, within the accuracy parameters. These data are valid both for the VArh functions and the Wh.

A maior presença de correntes harmônicas no sistema de distribuição, principalmente devido à geração distribuída, tem chamado atenção sobre suas possíveis consequências. O trabalho apresenta um método para a avaliação de harmônicas em um sistema elétrico através de um estimador de estados. A proposta é um método de supervisão da rede de distribuição utilizando o menor número de medidores possível. Isso foi feito identificando topologias de rede que viabilizam o uso de pseudomedidas no lugar de medidores. O método é aplicado a um estudo de caso baseado no modelo IEEE 13 barras e os resultados do estimador de estados foram comparados a uma simulação. Também é feita uma análise de sensibilidade do código, observando os resultados quando se adicionam erros sobre as medidas e sobre os parâmetros das linhas do sistema. / The growth of harmonic currents in distribution system, mainly due the distributed generation, is calling attention of the specialists to its possible consequences. This work presents a method to assessment of harmonics in an electric power system through a state estimator. The proposal is a method to monitor the distribution network using as few measurement devices as possible. It was performed identifying network topologies where a pseudomeasurement can replace a measurement device. The method was applied to a study case based on the IEEE 13 buses model and its results were compared to a simulation. A sensitivity analysis of the code also was performed, errors were added to measurements and lines parameters to assess the errors in the state estimator results.

Lorsqu'on focalise une impulsion laser femtoseconde ultraintense à très haut contraste sur une cible solide, le champ laser au foyer est suffisamment important pour ioniser la surface durant le front montant de l'impulsion et former un plasma. Au sein de ce plasma s'établit un gradient de densité résultant de l'expansion hydrodynamique du plasma. Ce plasma très dense, réfléchit le faisceau laser incident dans la direction spéculaire: on parle alors de miroir plasma. Comme l'interaction entre le laser et le miroir plasma est fortement non-linéaire, cela conduit à la génération d'harmoniques d'ordre élevé dans le faisceau réfléchi. Dans le domaine temporel, ce spectre d'harmonique est associé à un train d'impulsions attosecondes. Les objectifs de ma thèse étaient de contrôler expérimentalement cette génération d'harmoniques et d'en mesurer toutes les propriétés. Nous nous sommes intéressés dans un premier temps, à l'optimisation du signal harmonique, puis à la caractérisation spatiale en champ lointain du faisceau harmonique (divergence des harmoniques).Si la caractérisation et le contrôle de ces propriétés sont des points importants pour le développement de la source, ces résultats permettent également une meilleure compréhension de l'interaction laser-plasma à ultra-haute intensité. Ils nous ont notamment permis d'obtenir des informations cruciales sur les dynamiques électronique et ionique du plasma, démontrant ainsi qu'il est possible d'utiliser les harmoniques comme un diagnostic de l'interaction laser-plasma.Nous introduisons également une méthode complètement optique permettant de structurer un plasma in-situ. En tirant partie des propriétés de l'expansion d'un plasma, nous avons pu créer in-situ des réseaux plasmas transitoires, que nous avons ensuite exploités pour réaliser les premières mesures ptychographiques à des intensités de 10^19W/cm^2, permettant de mesurer entièrement, pour la première fois, les propriétés spatiales des harmoniques (taille de source et phase) dans le plan de leur génération. / When an ultra intense femtosecond laser with high contrast is focused on a solid target, the laser field at focus is sufficient enough to completely ionize the target surface during the rising edge of the laser pulse and form a plasma. This dense plasma entirely reflects the incident beam in the specular direction: this is a so-called plasma mirror. As the interaction between the laser and the plasma mirror is highly non-linear, it thus leads to the high harmonic generation (HHG) in the reflected beam. In the temporal domain, this harmonic spectrum is associated to a train of attosecond pulses.The aim of my PhD were to experimentally control this HHG and to measure the properties of the harmonics. We first studied the optimization of the harmonic signal, and then the spatial characterization of the harmonic beam in the far-field (harmonic divergence). These characterizations are not only important to develop an intense XUV/attosecond light source, but also to get a better understanding of the laser-matter interaction at very high intensity. We have thus been able to get crucial information of the electrons and ions dynamics of the plasma, showing that the harmonics can also be used as a diagnostic of the laser-plasma interaction.We then developed a new general approach for optically-controlled spatial structuring of overdense plasmas generated at the surface of initially plain solid targets. We demonstrate it experimentally by creating sinusoidal plasma gratings of adjustable spatial periodicity and depth, and study the interaction of these transient structures with an ultraintense laser pulse to establish their usability atrelativistically high intensities. We then show how these gratings can be used as a `spatial ruler' to determine the source size of the high-order harmonic beams roduced at the surface of an overdense plasma. These results open new directions both for the metrology of laser-plasma interactions and the emerging field of ultrahigh intensity plasmonics.