Dissertations / Theses: 'Inductive transfer'

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Momeneh, Arash. "Inductive contactless energy transfer systems for residential areas." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/462809.

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In recent years, contactless energy transfer systems have been developed and investigated widely. As evident, the transfer energy is performed without physical connection. This technology is classified according to power level and place of use. However, the most commonly used one is inductive contactless energy transfer system due to its higher efficiency. The inductive contactless system is responsible to deliver the electrical energy to the loads by means of a long winding loop and sliding transformers. In this system, the output converter and load are directly connected to the secondary side of transformer. Moreover, the secondary side transformer has the capability to move along the primary winding loop. According to this capability, and also possibility to construct long contactless system, it can be used as an electrical energy delivery system for mobile receivers. Also, the ICET technologies improve the safety of the final user by means of the elimination of electrical shocks. It is resulted from using a high-frequency resonant transformer which provides electrical isolation. This feature is particularly important in wet environments such as in swimming pools, gardens and bathrooms. Therefore, it is a good alternative system for implementing in the residential area instead of conventional systems. Implementation of the inductive contactless system in residential area presents several challenges. In this dissertation, several solutions are presented and discussed. In the first chapter, the concept of the contactless energy transfer system is explained. Also, the chapter classifies the contactless system according to the technology and the output power. In chapter two, a new adaptive control algorithm for the fully-controlled contactless energy transfer system is presented. The new adaptive algorithm operates dynamically with the load changes, resulting in maximum efficiency in all the load conditions. Moreover, the mathematical framework of the contactless system with new adaptive algorithm is presented. In chapter three, a partially-controlled inductive contactless system as an alternative to the fully-controlled topology is introduced. The features of the new topology are analyzed by considering several modulation techniques, including frequency modulation, phase modulation and quantum modulation. The performance of the new topology is evaluated and the best modulation technique is identified. The chapter is finished with the design of the new topology with the best modulation technique. In chapter four, the analysis, design and implementation of a simple and cost-effective technique to supply the residential contactless energy transfer system with multiple mobile loads is presents. The topology is based on the cascaded connection of a closed-loop buck converter and a high frequency resonant inverter operating in open loop which is loaded by several output passive rectifiers. The proposed system includes a sliding transformer to supply the mobile loads, leading to a safe and flexible location of loads. The theoretical analysis and design of the proposed system is based on a mathematical model derived using the first harmonic approximation. Selected experimental results are included to verify the system features. Finally, the dissertation concludes with remarks regarding the results.
En los últimos años, los sistemas de transmisión de energía sin contacto han sido ampliamente investigados y desarrollados. Como es evidente, en estos la transmisión de energía se realiza sin conexión física. Esta tecnología se suele clasificar de acuerdo al nivel de potencia y el lugar de utilización. Sin embargo, los más usados son los sistemas inductivos de trasmisión de energía sin contacto (Inductive contactless energy transfer systems, ICET) debido a su alta eficiencia. Los sistemas ICET envían la energía eléctrica a las cargas a través de grandes bobinados y transformadores sliding. En estos sistemas, la salida del convertidor y las cargas están directamente conectadas al lado secundario del transformador. Este, tiene la capacidad de moverse a través del bobinado primario. Debido a esta capacidad y a la posibilidad de construir sistemas de gran tamaño, pueden ser usados como sistemas de suministro de energía para receptores móviles. Por otro lado, las tecnologías ICET mejoran la seguridad de los usuarios finales ya que eliminan el riesgo de electrocución, como resultado del uso de transformadores resonantes de alta frecuencia que proveen un aislamiento eléctrico. Esta característica es particularmente importante en ambientes húmedos como las piscinas, jardines y baños. Además, es una buena alternativa para la implementación residencial, en lugar de los sistemas convencionales. La implementación de sistemas ICET en áreas residenciales presenta ciertos retos. En esta tesis de doctorado, se presentan diversas soluciones a estos. En el primer capítulo, el concepto de sistemas de transmisión de energía sin contacto es explicado y se presenta una clasificación de acuerdo al nivel de potencia. En el segundo capítulo, se propone un algoritmo de control adaptativo para sistemas de transmisión de energía sin contacto totalmente controlados. Este algoritmo adaptativo opera dinámicamente con los cambios de carga, alcanzando la máxima eficiencia ante diferentes condiciones de carga. En el capítulo se describe el modelado matemático del algoritmo propuesto. En el tercer capítulo, se introduce un sistema sin contacto inductivo parcialmente controlado como alternativa a la topología totalmente controlada. Se analizan las características de esta nueva topología considerando diferentes técnicas de modulación, incluyendo la modulación de frecuencia, la modulación de fase y la modulación Quantum. Luego, se evalúa el desempeño de esta nueva topología y de identifica la técnica de modulación más adecuada. Finalmente, se presenta el diseño de la nueva topología con la técnica de modulación seleccionada. En el cuarto capítulo se presenta el análisis, diseño e implementación de una técnica simple y efectiva en términos de costo para el suministro energía inalámbrica residencial con múltiples cargas móviles. La topología se basa en una conexión en cascada de un convertidor buck de lazo cerrado y de un inversor resonante de alta frecuencia operando en lazo abierto, que es cargado con varios rectificadores pasivos. El sistema propuesto incluye un transformador sliding para abastecer las cargas móviles, lo que permite una ubicación flexible y segura de las mismas. El análisis teórico y el diseño del sistema propuesto se basan en modelos matemáticos derivados del uso de la aproximación del primer armónico. Se incluyen resultados experimentales para verificar las características del sistema. Finalmente, se presentan las conclusiones más importantes de los resultados obtenidos

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Puccetti, Giovanni <1986&gt. "Enhancement of inductive power transfer with flat spiral resonators." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7115/.

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The aim of this thesis is to develop a depth analysis of the inductive power transfer (or wireless power transfer, WPT) along a metamaterial composed of cells arranged in a planar configuration, in order to deliver power to a receiver sliding on them. In this way, the problem of the efficiency strongly affected by the weak coupling between emitter and receiver can be obviated, and the distance of transmission can significantly be increased. This study is made using a circuital approach and the magnetoinductive wave (MIW) theory, in order to simply explain the behavior of the transmission coefficient and efficiency from the circuital and experimental point of view. Moreover, flat spiral resonators are used as metamaterial cells, particularly indicated in literature for WPT metamaterials operating at MHz frequencies (5-30 MHz). Finally, this thesis presents a complete electrical characterization of multilayer and multiturn flat spiral resonators and, in particular, it proposes a new approach for the resistance calculation through finite element simulations, in order to consider all the high frequency parasitic effects. Multilayer and multiturn flat spiral resonators are studied in order to decrease the operating frequency down to kHz, maintaining small external dimensions and allowing the metamaterials to be supplied by electronic power converters (resonant inverters).

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Worgan, Paul. "Inductive energy transfer systems for mobile and wearable computing." Thesis, University of Bristol, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.720835.

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Lu, Ying. "Transfer Learning for Image Classification." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEC045/document.

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Lors de l’apprentissage d’un modèle de classification pour un nouveau domaine cible avec seulement une petite quantité d’échantillons de formation, l’application des algorithmes d’apprentissage automatiques conduit généralement à des classifieurs surdimensionnés avec de mauvaises compétences de généralisation. D’autre part, recueillir un nombre suffisant d’échantillons de formation étiquetés manuellement peut s’avérer très coûteux. Les méthodes de transfert d’apprentissage visent à résoudre ce type de problèmes en transférant des connaissances provenant d’un domaine source associé qui contient beaucoup plus de données pour faciliter la classification dans le domaine cible. Selon les différentes hypothèses sur le domaine cible et le domaine source, l’apprentissage par transfert peut être classé en trois catégories: apprentissage par transfert inductif, apprentissage par transfert transducteur (adaptation du domaine) et apprentissage par transfert non surveillé. Nous nous concentrons sur le premier qui suppose que la tâche cible et la tâche source sont différentes mais liées. Plus précisément, nous supposons que la tâche cible et la tâche source sont des tâches de classification, tandis que les catégories cible et les catégories source sont différentes mais liées. Nous proposons deux méthodes différentes pour aborder ce problème. Dans le premier travail, nous proposons une nouvelle méthode d’apprentissage par transfert discriminatif, à savoir DTL(Discriminative Transfer Learning), combinant une série d’hypothèses faites à la fois par le modèle appris avec les échantillons de cible et les modèles supplémentaires appris avec des échantillons des catégories sources. Plus précisément, nous utilisons le résidu de reconstruction creuse comme discriminant de base et améliore son pouvoir discriminatif en comparant deux résidus d’un dictionnaire positif et d’un dictionnaire négatif. Sur cette base, nous utilisons des similitudes et des dissemblances en choisissant des catégories sources positivement corrélées et négativement corrélées pour former des dictionnaires supplémentaires. Une nouvelle fonction de coût basée sur la statistique de Wilcoxon-Mann-Whitney est proposée pour choisir les dictionnaires supplémentaires avec des données non équilibrées. En outre, deux processus de Boosting parallèles sont appliqués à la fois aux distributions de données positives et négatives pour améliorer encore les performances du classificateur. Sur deux bases de données de classification d’images différentes, la DTL proposée surpasse de manière constante les autres méthodes de l’état de l’art du transfert de connaissances, tout en maintenant un temps d’exécution très efficace. Dans le deuxième travail, nous combinons le pouvoir du transport optimal (OT) et des réseaux de neurones profond (DNN) pour résoudre le problème ITL. Plus précisément, nous proposons une nouvelle méthode pour affiner conjointement un réseau de neurones avec des données source et des données cibles. En ajoutant une fonction de perte du transfert optimal (OT loss) entre les prédictions du classificateur source et cible comme une contrainte sur le classificateur source, le réseau JTLN (Joint Transfer Learning Network) proposé peut effectivement apprendre des connaissances utiles pour la classification cible à partir des données source. En outre, en utilisant différents métriques comme matrice de coût pour la fonction de perte du transfert optimal, JTLN peut intégrer différentes connaissances antérieures sur la relation entre les catégories cibles et les catégories sources. Nous avons effectué des expérimentations avec JTLN basées sur Alexnet sur les jeux de données de classification d’image et les résultats vérifient l’efficacité du JTLN proposé. A notre connaissances, ce JTLN proposé est le premier travail à aborder ITL avec des réseaux de neurones profond (DNN) tout en intégrant des connaissances antérieures sur la relation entre les catégories cible et source
When learning a classification model for a new target domain with only a small amount of training samples, brute force application of machine learning algorithms generally leads to over-fitted classifiers with poor generalization skills. On the other hand, collecting a sufficient number of manually labeled training samples may prove very expensive. Transfer Learning methods aim to solve this kind of problems by transferring knowledge from related source domain which has much more data to help classification in the target domain. Depending on different assumptions about target domain and source domain, transfer learning can be further categorized into three categories: Inductive Transfer Learning, Transductive Transfer Learning (Domain Adaptation) and Unsupervised Transfer Learning. We focus on the first one which assumes that the target task and source task are different but related. More specifically, we assume that both target task and source task are classification tasks, while the target categories and source categories are different but related. We propose two different methods to approach this ITL problem. In the first work we propose a new discriminative transfer learning method, namely DTL, combining a series of hypotheses made by both the model learned with target training samples, and the additional models learned with source category samples. Specifically, we use the sparse reconstruction residual as a basic discriminant, and enhance its discriminative power by comparing two residuals from a positive and a negative dictionary. On this basis, we make use of similarities and dissimilarities by choosing both positively correlated and negatively correlated source categories to form additional dictionaries. A new Wilcoxon-Mann-Whitney statistic based cost function is proposed to choose the additional dictionaries with unbalanced training data. Also, two parallel boosting processes are applied to both the positive and negative data distributions to further improve classifier performance. On two different image classification databases, the proposed DTL consistently out performs other state-of-the-art transfer learning methods, while at the same time maintaining very efficient runtime. In the second work we combine the power of Optimal Transport and Deep Neural Networks to tackle the ITL problem. Specifically, we propose a novel method to jointly fine-tune a Deep Neural Network with source data and target data. By adding an Optimal Transport loss (OT loss) between source and target classifier predictions as a constraint on the source classifier, the proposed Joint Transfer Learning Network (JTLN) can effectively learn useful knowledge for target classification from source data. Furthermore, by using different kind of metric as cost matrix for the OT loss, JTLN can incorporate different prior knowledge about the relatedness between target categories and source categories. We carried out experiments with JTLN based on Alexnet on image classification datasets and the results verify the effectiveness of the proposed JTLN in comparison with standard consecutive fine-tuning. To the best of our knowledge, the proposed JTLN is the first work to tackle ITL with Deep Neural Networks while incorporating prior knowledge on relatedness between target and source categories. This Joint Transfer Learning with OT loss is general and can also be applied to other kind of Neural Networks

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Lu, Ming. "Synergetic Attenuation of Stray Magnetic Field in Inductive Power Transfer." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/78621.

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Significant stray magnetic field exists around the coils when charging the electric vehicles (EVs) with inductive power transfer (IPT), owning to the large air gap between the transmitter and receiver. The methods for field attenuation usually introduce extra losses and reduce the efficiency. This study focuses on the synergetic attenuation of stray magnetic field which is optimized simultaneously with the efficiency. The optimization is realized with Pareto front. In this dissertation, three methods are discussed for the field attenuation. The first method is to tune the physical parameters of the winding, such as the inner radii, outer radii, distribution of the turns, and types of the litz wires. The second method is to add metal shields around the IPT coils, in which litz wires are used as shields to reduce the shielding losses. The third method is to control the phases of winding currents, which avoids increasing the size and weight of the IPT coils. To attenuate the stray magnetic field by tuning the physical parameters, the conventional method is to sweep all the physical parameters in finite-element simulation. This takes thousands of simulations to derive the Pareto front, and it's especially time-consuming for three-dimensional simulations. This dissertation demonstrates a faster method to derive the Pareto front. The windings are replaced by the lumped loops. As long as the number of turns for each loop is known, the efficiency and magnetic field are calculated directly from the permeance matrices and current-to-field matrices. The sweep of physical parameters in finite-element simulation is replaced by the sweep of the turns numbers for the lumped loops in calculation. Only tens of simulations are required in the entire procedure, which are used to derive the matrices. An exemplary set of coils was built and tested. The efficiency from the matrix calculation is the same as the experimental measurement. The difference for stray magnetic field is less than 12.5%. Metal shields attenuate the stray magnetic field effectively, but generates significant losses owning to the uneven distribution of shield currents. This dissertation uses litz wires to replace the conventional plate shield or ring shield. Skin effect is eliminated so the shield currents are uniformly distributed and the losses are reduced. The litz shields are categorized to two types: shorted litz shield and driven litz shield. Circuit models are derived to analyze their behaviors. The concept of lumped-loop model is applied to derive the Pareto front of efficiency versus stray magnetic field for the coils with litz shield. In an exemplary IPT system, coils without metal shield and with metal shields are optimized for the same efficiency. Both the simulation and experimental measurement verify that the shorted litz shield has the best performance. The stray magnetic field is attenuated by 65% compared to the coils without shield. This dissertation also introduces the method to attenuate the stray magnetic field by controlling the phases of winding currents. The magnetic field around the coils is decomposed to the component in the axial direction and the component in the radial direction. The axial component decreases with smaller phase difference between windings' currents, while the radial component exhibits the opposite property. Because the axial component is dominant around the IPT coils, decreasing the phase difference is preferred. The dual-side-controlled converter is applied for the circuit realization. Bridges with active switches are used for both the inverter on the transmitter side and the rectifier on the receiver side. The effectiveness of this method was verified both in simulation and experiment. Compared to the conventional series-series IPT with 90° phase difference between winding currents, stray magnetic field was attenuated by up to 30% and 40% when the phase differences of winding currents are 50° and 40°, respectively. Furthermore, an analytical method is investigated to calculate the proximity-effect resistance of the planar coils with ferrite plate. The objective of this method is to work together with the fast optimization which uses the lumped-loop model. The existence of the ferrite plate complicates the calculation of the magnetic field across each turn which is critical to derive the proximity-effect resistance. In this dissertation, the ferrite plate is replaced by the mirrored turns according to the method of image. The magnetic fields are then obtained from Ampere's Law and Biot-Savart Law. Up to 200 kHz, the difference of the proximity-effect resistance is less than 15% between calculation and measurement.
Ph. D.

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Pinuela, Manuel. "Ambient RF energy harvesting and efficient DC-load inductive power transfer." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/28090.

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This thesis analyses in detail the technology required for wireless power transfer via radio frequency (RF) ambient energy harvesting and an inductive power transfer system (IPT). Radio frequency harvesting circuits have been demonstrated for more than fifty years, but only a few have been able to harvest energy from freely available ambient (i.e. non-dedicated) RF sources. To explore the potential for ambient RF energy harvesting, a city-wide RF spectral survey was undertaken in London. Using the results from this survey, various harvesters were designed to cover four frequency bands from the largest RF contributors within the ultra-high frequency (0.3 to 3 GHz) part of the frequency spectrum. Prototypes were designed, fabricated and tested for each band and proved that approximately half of the London Underground stations were found to be suitable locations for harvesting ambient RF energy using the prototypes. Inductive Power Transfer systems for transmitting tens to hundreds of watts have been reported for almost a decade. Most of the work has concentrated on the optimization of the link efficiency and have not taken into account the efficiency of the driver and rectifier. Class-E amplifiers and rectifiers have been identified as ideal drivers for IPT applications, but their power handling capability at tens of MHz has been a crucial limiting factor, since the load and inductor characteristics are set by the requirements of the resonant inductive system. The frequency limitation of the driver restricts the unloaded Q-factor of the coils and thus the link efficiency. The system presented in this work alleviates the use of heavy and expensive field-shaping techniques by presenting an efficient IPT system capable of transmitting energy with high dc-to-load efficiencies at 6 MHz across a distance of 30 cm.

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Ferraro, Luigi. "Design and control of inductive power transfer system for electric vehicle charging." Phd thesis, Toulouse, INPT, 2017. http://oatao.univ-toulouse.fr/17819/1/Ferraro_L.pdf.

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During the last decades, public awareness of the environmental, economic and social consequences of using fossil fuels has considerably grown. Moreover, not only the supply of fossil resources is limited, but also the environmental impact represents a relevant issue, so leading to an increased consideration of clean and renewable alternatives to traditional technologies. During recent years, the automotive industry has shown a growing interest in electric and hybrid electric vehicles. However, the transition to all-electric transportation is now limited by the high cost of the vehicles, the limited range and the long recharging time. Distributed IPT (inductive power transfer) systems can be the solution to the range restrictions of EVs by charging the vehicle while driving thanks to, a set of loosely coupled coils, so also reducing required battery size as well as overall cost of the vehicle. The concept of wireless power transfer via magnetic induction was introduced two decades ago. Nowadays, this technology is becoming more efficient and more suitable for new applications. This dissertation made an effort to address the requirements of IPT EV battery charging system with high efficiency and good tolerance to misalignment. A survey of a typical IPT for EV application has been reported, while a concentrated DD-BP solution has been proposed in order to enhance the IPT charging system capability of transferring power to a stationary EV with good efficiency and good tolerance to movement. The current trend in EV battery charging application is represented by the lamped coil system, whose different structures have been reviewed. Moreover, this thesis presented the design of a charging pad magnetic structure, called Double D pad combined with a Bipolar secondary pad, in order to enhance coupling performance. A finite element magnetic analysis has been performed in order to obtain the electric parameters of the proposed magnetic coupler. Furthermore, a mathematical model has been developed by considering the different sides of the system. The mathematical model allows to accurately predict the behavior of inductive coils and coreless transformer. A set of simulation has been carried out in order to compare the analytical and simulated results. The proposed EV IPT system has shown the feasibility of using fixed frequency, single pick up system to transfer power efficiently across a large air gap, with variable coupling. This result has been reached by means of proper design of the charging pad magnetics, of tuning network and of a pick-control based on a buck boost converter topology.

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Muñiz, García Claudia. "Rapid Energy Transfer to an Energy Buffer." Thesis, KTH, Kommunikationssystem, CoS, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91941.

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This master thesis introduces a new technology applicable to nearly all mobile and portable electrical devices since all of them need energy to operate. This thesis attempts to cut the last wire - this one the wire to the primary power source. In other words, fast and efficient wireless energy transference through a strong, focused near magnetic field whose fast attenuation will avoid interference with surrounding communication systems or human harm. This energy is transferred to and will be stored inside the mobile device where nothing but a small and simple secondary circuit has been placed. The thesis project began by creating an initial SPICE computer model, providing an easy and rapid way of testing both convergence and feasibility of the topology as the design evolved from the well-known and widely used Switch Model Power Supply technology through to the detailed design and implementation of the prototype, including supporting the iterative process of testing and optimizing, all stages are carefully described in the document. The thesis shows both theoretically and practically that this idea is feasible and capable of power transmission.
Detta examensarbete introducerar en ny teknologi som är applicerbar till de flesta mobila och portabla elektriska apparater då dessa behöver energi för att fungera. Detta arbete försöker klippa den sista ledningen den som leder till den primära kraftkällan. Med andra ord, är denna teknik en snabb och effektiv trådlös energiöverföring genom ett starkt, fokuserat närbeläget magnetfält. Tack vare magnetfältets kraftiga dämpning undviks interferens med intilliggande kommunikationssystem eller personskador. Denna energi är överförd till, och lagras inuti en bärbar apparat där endast en liten och enkel sekundärkrets har placerats. Examensarbetsprojektet påbörjades med skapandet av en inledande SPICE datormodell. Modellen möjliggjorde ett enkelt och snabbt sätt att testa både konvergens och genomförbarhet av topologin samtidigt som designen utvecklades från den välkända och vitt använda Switch Power Supply-teknologin till den detaljerade designen och implementationen av prototypen. Modellen stöttade samtidigt den iterativa processen av test och optimering. Alla faser är utförligt beskrivna i rapporten och arbetet visar både teoretiskt och praktiskt att denna idé är genomförbar och möjliggör kraftöverföring.

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Pimperton, M. G. "The meatgrinder : an efficient current-multiplying inductive energy storage and transfer circuit." Thesis, Loughborough University, 1990. https://dspace.lboro.ac.uk/2134/10828.

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The meatgrinder is a high-efficiency inductive energy storage and transfer circuit which may be used to supply high-current pulsed power requirements in applications such as electromagnetic propulsion. It overcomes the inherent 25% efficiency limit when transferring energy between uncoupled inductors and simultaneously provides current multiplication. An unloaded six-step demonstration circuit has been used to multiply current from 7A to 76A at an efficiency of 44%, and a single-step demonstration circuit has been used to multiply the current in an uncoupled load induct or from lOA to 30A, the efficiency of energy transfer being 31%. Both circuits use power MOSFETs for switching. These circuits have been used in conjunction with theoretical analysis and computer simulation to study the design and performance of the meatgrinder. Investigations have been carried out in order to confirm the basic theory, to clarify the details of circuit operation, and to provide the information necessary for future feasibility studies.

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Moghaddami, Masood. "Design Optimization of Inductive Power Transfer Systems for Contactless Electric Vehicle Charging Applications." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3853.

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Contactless Electric Vehicle (EV) charging based on magnetic resonant induction is an emerging technology that can revolutionize the future of the EV industry and transportation systems by enabling an automated and convenient charging process. However, in order to make this technology an acceptable alternative for conventional plug-in charging systems it needs to be optimized for different design measures. Specifically, the efficiency of an inductive EV charging system is of a great importance and should be comparable to the efficiency of conventional plug-in EV chargers. The aim of this study is to develop solutions that contribute to the design enhancement of inductive EV charging systems. Specifically, generalized physics-based design optimization methods that address the trade-off problem between several key objectives including efficiency, power density, misalignment tolerance, and cost efficiency considering critical constraints are developed. Using the developed design methodology, a 3.7kW inductive charging system with square magnetic structures is investigated as a case study and a prototype is built to validate the optimization results. The developed prototype achieves 93.65% efficiency (DC-to-DC) and a power density of 1.65kW/dm3. Also, self-tuning power transfer control methods with resonance frequency tracking capability and bidirectional power transfer control are presented. The proposed control methods enhance the efficiency of power converters and reduce the Electromagnetic Interference (EMI) by enabling soft-switching operations. Several simplified digital controllers are developed and experimentally implemented. The controllers are implemented without the use of DSP/FPGA solutions. Experimental tests show that of the developed simplified controllers can effectively regulate the power transfer around the desired value. Moreover, the experiments show that compared to conventional converters, the developed converters can achieve 4% higher efficiency at low power levels. Moreover, enhanced matrix converter topologies that can achieve bidirectional power transfer and high efficiency with a reduced number of switching elements are introduced. The self-tuning controllers are utilized to design and develop control schemes for bidirectional power transfer regulation. The simulation analyses and experimental results show that the developed matrix converters can effectively establish bidirectional power transfer at the desired power levels with soft-switching operations and resonance frequency tracking capability. Specifically, a direct three-phase AC-AC matrix converter with a reduced number of switches (only seven) is developed and built. It is shown that the developed converters can achieve efficiencies as high as 98.54% at high power levels and outperform conventional two-stage converters.

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Fotopoulou, Kyriaki. "Inductive wireless power transfer for RFID & embedded devices : coil misalignment analysis and design." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/10907.

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Radio frequency inductive coupling is extensively employed for wireless powering of embedded devices such as low power passive near-field RFID systems and implanted sensors. The efficiency of low power inductive links is typically less than 1%and is characterised by very unfavourable coupling conditions, which can vary significantly due to coil position and geometry. Although, a considerable volume of knowledge is available on this topic, most of the existing research is focused on the circuital modeling of the transformer action between the external and implanted coils. The practical issues of coil misalignment and orientation and their implications on transmission characteristics of RF links have been overlooked by researchers. The aim of this work is to present a novel analytical model for near-field inductive power transfer incorporating misalignment of the RF coil system. In this thesis the influence of coil orientation, position and geometry on the link efficiency is studied by approaching the problem from an electromagnetic perspective. In implanted devices some degree of misalignment is inevitable between external and implanted coils due to anatomical requirements. First two types of realistic misalignments are studied; a lateral displacement of the coils and an angular misalignment described as a tilt of the receiver coil. A loosely coupled system approximation is adopted since, for the coil dimensions and orientations envisaged, the mutual inductance between the transmitter and receiver coils can be neglected. Following this, formulae are derived for the magnetic field at the implanted coil when it is laterally and angularly misaligned from the external coil and a new power transfer function presented. The magnetic field solution is carried out for a number of practical antenna coil geometries currently popular in RFID and biomedical domains, such as planar and printed square, and circular spirals as well as conventional air-cored and ferromagnetic solenoids. In the second phase of this thesis, the results from the electromagnetic modeling are embodied in a near-field loosely coupled equivalent circuit for the inductive link. This allows us to introduce a power transfer formula incorporating for the first time coil characteristics and misalignment factors. This novel power transfer function allows a comparison between different coil structures such as short solenoids, with air or ferromagnetic core, planar and printed spirals with respect to power delivered at the receiver and its relative position to the transmitter. In the final stage of this work, the experimental verification of the model shows close agreement with the theoretical predictions. Using this analysis a formal design procedure is suggested that can be applied on a larger scale compared to existing methods. The main advantage of this technique is that it can be applied to a wide range of implementations without the limitations imposed by numerical modeling and existing circuital methods. Consequently, the designer has the flexibility to identify the optimum coil geometry for maximum power transfer and misalignment tolerance that suit the specifications of the application considered. This thesis concludes by suggesting a new optimisation technique for maximum power transfer with respect to read range, coil orientation, geometry and operating frequency. Finally, the limitations of this model are reiterated and possible future development of this research is discussed.

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Simonazzi, Mattia. "Misalignment tolerant model and force calculation in a resonator array for inductive power transfer." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18981/.

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In this work, an inductive power transfer (IPT) system composed of an array of multiple magnetically coupled resonant inductors (cells) has been considered, allowing the transmission distance to be increased or the misalignment between the emitter and receiver coils to be considered. The analysis of the arrays can be carried out with the theory of magnetoinductive waves (MIW) or with circuit theory; the latter approach has been followed. The impedance matrix of the resonator array has been modelled for different receiver shapes and dimensions. Moreover, it has been expressed as a function of the space improving the accuracy of the model. The model has been exploited to calculate all the currents and voltages of the system. In first approximation, only the displacement in the MIW propagation direction has been considered, whereas the contribution of the receiver is expressed as a defect and becomes a function of the space as the mutual inductances between the circuits vary according to the receiver position. The self- and mutual inductance coefficients have been evaluated for each circuit of the system by applying the partial inductance method, whose formulas have been implemented in Matlab environment. These results have been validated by means of magnetostatic FEM analysis of the system using a commercial software. Experimental measurements on a prototype of a 1-D resonator array have been performed, confirming the calculated values of the currents and as a consequence, of the mutual inductances. The last part of the thesis is devoted to the calculation of the mechanical forces of electromagnetic origin experienced by the receiver over the array, as a result of the interaction between the whole magnetic field - generated by all the array cells - and the current circulating in the receiver. These forces have been theoretically discussed first, with a subsequent implementation of the calculation in Matlab environment and analysis of the obtained results.

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13

Zheng, Cong. "Loosely Coupled Transformer and Tuning Network Design for High-Efficiency Inductive Power Transfer Systems." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/52893.

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Transfer signal without wire has been widely accepted after the introduction of cellular technology and WiFi technology, hence the power cable is the last wire that has yet to be eliminated. Inductive power transfer (IPT) has drawn substantial interest in both academia and industry due to its advantages including convenience, nonexistence of cable and connector, no electric shock issue, ability to work under some extreme environment, and so on. After performing thorough literature review of IPT systems, two major drawbacks including low power efficiency and coil displacement sensitivity are identified as the main obstacles that have to be solved in order for these systems to reach full functionality and compete with existing wired solutions. To address the limitations and design challenges in the IPT systems, a detailed electric circuit modeling of individual part of the IPT DC-DC stage is performed. Several resonant DC-AC inverters and output AC-DC rectifiers are compared based on their performance and feasibility in inductive charging applications. Different equivalent circuit models for the loosely coupled transformer (LCT) are derived which allows for better understanding on how power is distributed among the circuit components. Five compensation networks to improve the power transfer efficiency are evaluated and their suitable application occasions are identified. With comprehensive circuit model analysis, the influence of the resonant compensation tank parameters has been investigated carefully for efficient power transfer. A novel tuning network parameters design methodology is proposed based on multiple given requirement such as battery charging profile, geometry constraints and operating frequency range, with the aim of avoiding bifurcation phenomenon during the whole charging process and achieving decent efficiency. A 4-kW hardware prototype based on the proposed design approach is built and tested under different gap and load conditions. Peak IPT system DC-DC efficiencies of 98% and 96.6% are achieved with 4-cm and 8-cm air gap conditions, which is comparable to the conventional plug-in type or wired charging systems for EVs. A long-hour test with real EV batteries is conducted to verify the wireless signal transmission and CC/CV mode seamless transition during the whole charging profile without bifurcation. To reduce the IPT system sensitivity to the gap variation or misalignment, a novel LCT design approach without additional complexity for the system is proposed. With the aid of FEA simulation software, the influence of coil relative position and geometry parameters on the flux distribution and coupling coefficient of the transmitter and receiver is studied from an electromagnetic perspective. An asymmetrical LCT based on the proposed design method is built to compare with a traditional symmetrical LCT. With fixed 10-mm gap and 0 to 40-mm misalignment variation, the coupling coefficient for the symmetrical LCT drops from 0.354 to 0.107, and the corresponding efficiency decrease is 16.6%. The operating frequency variation is nearly 100 kHz to maintain same input/output condition. When employing the proposed asymmetrical LCT, the coupling coefficient changes between 0.312 and 0.273, and the maximum efficiency deviation is kept within 0.67% over the entire 40-mm misalignment range. Moreover, the required frequency range to achieve same operation condition is less than 10 kHz. Lastly, some design considerations to further improve the IPT system efficiency are proposed on the basis of the designed asymmetrical LCT geometry. For given circuit specifications and LCT coupling conditions, determination of the optimal primary winding turns number could help achieve minimal winding loss and core loss. For lower output power, the optimal primary winding turns number tends to be larger compared to that for higher output power IPT system. Two asymmetrical LCT with similar dimension but different number of turns are built and tested with a 100-W hardware prototype for laptop inductive charging. The proposed efficiency improvement methodology is validated by the winding loss and core loss from experimental results.
Ph. D.

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14

Bou, Balust Elisenda. "Wireless power transfer : fueling the dots." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/456820.

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Resonant Inductive Coupling Wireless Power Transfer (RIC-WPT) has been proven to provide very high power transfer efficiencies (above 80%) for moderate distances, and is hence foreseen as a key technology to enable wireless power transfer to a myriad of different devices and related applications. Due to the multidisciplinary nature of the WPT underlying principles, several approaches have been provided to analyze RIC-WPT systems from different perspectives (encompassing Electromagnetic fields, Circuit models and Optics), but they have failed to provide a unified model to understand and ultimately to design the behaviour of such systems. This thesis is therefore aimed to, first, provide a multi-modal RIC-WPT complete model oriented to the design and in turn optimisation of RIC-WPT systems and, secondly, to explore and characterize the fundamental challenges precluding the widespread deployment of RIC-WPT and thereby accordingly to yield a set of design guidelines to overcome them. Finally, and due to the fact that multi-node RIC-WPT systems are key to the adoption of this technology, this thesis models, characterizes and analyzes Multiple-Input Multiple-Output RIC WPT Systems, making special emphasis on their scalability.
La transferencia inalámbrica de potencia basada en acoplamiento resonante inductivo (RIC-WPT) ha demostrado ser capaz de proporcionar eficiencias muy altas en la transferencia de potencia (hasta 80%) a distancias moderadas, de modo que ésta se anticipa por tanto como una tecnología clave para posibilitar la transferencia inalámbrica de energía a una miríada de diferentes dispositivos y sus aplicaciones asociadas. Debido a la naturaleza multisciplinar de los principios que rigen los sistemas RICWPT, se han propuesto varias aproximaciones para analizar los sistemas RIC-WPT desde diferentes perspectivas (bien sean campos electromagnéticos, modelos circuitales, u óptica), pero no se ha conseguido proporcionar un modelo unificado que permita la comprensión y, en última instancia, el diseño del comportamiento y las prestaciones de estos sistemas. Esta tesis tiene por tanto como objeto, primero, proporcionar un modelo completo multi-modo de la tecnología RIC-WPT, orientado al diseño y a su vez la optimización de estos sistemas, y, como segundo foco, el explorar y caracterizar los retos fundamentales que todavía evitan un amplio despliegue de los sistemas RIC-WPT, ofreciendo en consonancia un conjunto de pautas de diseño para sobreponerlos. Finalmente, y debido al hecho de que los sistemas RIC-WPT con múltiples nodos son cruciales para la adopción de esta tecnología, en esta tesis doctoral se modelan, caracterizan y analizan los sistemas RIC-WPT de entrada y salida múltiple, con un especial énfasis en sus tendencias de escalabilidad.

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15

Gori, Paul-Antoine. "Transmission dynamique d'énergie par induction : application au véhicule électrique." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLC063/document.

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L’autonomie limitée du véhicule électrique est le premier frein au développement du marché de l’électrique. La charge inductive dynamique répond à ce problème, en offrant de charger son véhicule en roulant. La principale difficulté est de gérer les variations importantes du couplage magnétique lors du déplacement du véhicule, et ce pendant le transfert de puissance. Une précédente thèse dans l’équipe de recherche sur un prototype de 3 kW avait abouti au concept de recopie de tension, qui stabilise la tension en sortie du coupleur malgré la variation de couplage, et facilite notablement la conception du convertisseur DC/DC faisant interface avec la batterie. La thèse présentée ici porte sur l’adaptation du système pour fonctionner de 20 kW à 30 kW. Cette montée en puissance n’est pas évidente, du fait des importantes contraintes électriques sur les bobines du coupleur (1,4 kV sur le système de 3 kW), et du champ rayonné limité par des références normatives. Tout d’abord, nous proposons une nouvelle commande du circuit résonnant, qui permet de modifier le dimensionnement pour aboutir à des contraintes électriques plus faibles tout en conservant la recopie de tension. Ensuite, une forme de bobine en huit est étudiée pour aider à réduire le champ rayonné. Enfin, une démarche de dimensionnement est établie pour la partie électrique du système, ainsi que pour le coupleur magnétique, alliant modèle analytique et simulations à éléments finis et réduisant considérablement les temps de simulations. Les résultats de l’évaluation des performances du système dimensionné pour la haute puissance sont prometteurs
The limited electric-vehicle distance range is the main reason hindering the development of the electric transportation market. Dynamic inductive charging solves this problem, offering the possibility to charge while driving. The main issue consists in handling wide magnetic coupling variations when the vehicle is moving, while charging. A previous thesis in the research team on a 3-kW prototype led to the concept of voltage copying, which stabilises the coupler output voltage despite the varying coupling, making it easier to design the DC/DC converter linking the coupler to the battery. The hereby thesis deals with adapting this system to transfer from 20 kW to 30 kW. Raising the power is no small matter, due to the high electrical constraints on the coupled coils (1.4 kV on the 3-kW system), and the radiated field, limited by standardised thresholds. Firstly, a new control of the resonating circuit is proposed, allowing to change the system design to get lower electrical constraints and maintaining voltage copying properties. Then, an eight-shape coil was investigated in order to reduce the radiated field. Finally, a design method was conceived for the electrical part of the system, as well as the magnetic coupler, using jointly analytical models and finite element simulations to reduce simulation times. Results of the evaluated performance for such a high-power system are quite promising

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Alashgar, Deeb Elian. "Development of the inductive coupling wireless power transfer system with a high lateral misalignment tolerance." Thesis, https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB13155952/?lang=0, 2020. https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB13155952/?lang=0.

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Cirimele, Vincenzo. "Design and Integration of a Dynamic IPT System for Automotive Applications." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS032/document.

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La transmission inductive de puissance (IPT) pour les véhicules électriques est une technologie émergente prometteuse qui semble capable d'améliorer l'acceptation de la mobilité électrique. Au cours des deux dernières décennies, de nombreux chercheurs ont démontré la faisabilité et la possibilité de l'utiliser pour remplacer les systèmes conducteurs classiques pour la charge de la batterie à bord du véhicule. Actuellement de nombreux efforts visent à étendre la technologie IPT vers son utilisation pour la charge pendant le mouvement du véhicule. Cette application, généralement appelée IPT dynamique, vise à surmonter la limite représentée par les arrêts prolongés nécessaires pour la recharge introduisant également la possibilité de réduction de la capacité de la batterie installée à bord du véhicule. Un système IPT est essentiellement basé sur la résonance de deux inducteurs magnétiquement couplés, l'émetteur, placé sur ou sous le sol, et le récepteur, placé sous le plancher du véhicule. La gamme de fréquence de fonctionnement typique pour les applications automobiles va de 20 kHz à environ 100 kHz. Le couplage entre les deux inductances s'effectue à travers un entrefer important, généralement d'environ 10-30 cm. Cette thèse présente les résultats des activités de recherche visant à la création d'un prototype pour l'IPT dynamique orienté vers le transport privé. A partir d'une analyse de l'état de l'art et des projets de recherche en cours dans ce domaine, ce travail présente le développement d'un modèle de circuit capable de décrire les phénomènes électromagnétiques à la base du transfert de puissance et l'interface avec l'électronique de puissance. Les analyses effectuées à travers le modèle développé fournissent la base pour la conception et la mise en œuvre d'un convertisseur dédié à faible coût et efficacité élevée pour l'alimentation du côté transmetteur. Une architecture générale de l'électronique de puissance qui gère le côté récepteur est proposée avec les circuits de protection supplémentaires. Une méthodologie pour la conception intégrée de la structure magnétique est illustrée. Cette méthodologie couvre les aspects de l'interface avec l'électronique de puissance, l'intégration sur un véhicule existant et l'installation sur l'infrastructure routière. Une série d'activités visant à la réalisation d'un site d'essai dédié sont présentées et discutées. En particulier, les activités liées à la création de l'infrastructure électrique ainsi que les questions et les méthodes d'implantation des émetteurs dans le revêtement routier sont présentées. L'objectif final est la création d'une ligne de recharge IPT dédiée de 100 mètres de long. Enfin, une méthodologie d'évaluation de l'exposition humaine est présentée et appliquée à la solution développée
Inductive power transmission (IPT) for electric vehicles (EVs) is a promising emergent technology that seems able to improve the electric mobility acceptance. In the last two decades many researchers have proved its feasibility and the possibility to use it to replace the common conductive systems for the charge of the on-board battery. Many efforts are currently aimed to extend the IPT technology towards its use for the charge during the vehicle motion. This application, commonly indicated as dynamic IPT, is aimed to overcome the limit represented by the long stops needed for the recharge introducing also the possibility of reducing the battery capacity installed on vehicle. An IPT system is essentially based on the resonance of two magnetically coupled inductors, the transmitter, placed on or under the ground, and the receiver, placed under the vehicle floor. The typical operating frequency range for the EVs application goes from 20 kHz to approximately 100 kHz. The coupling between the two inductors takes place through a large air-gap, usually about 10-30 cm. This thesis presents the results of the research activities aimed to the creation of a prototype for the dynamic IPT oriented to the private transport. Starting from an analysis of the state of the art and the current research projects on this domain, this work presents the development of a circuit model able to describe the electro- magnetic phenomena at the base of the power transfer and the interface with the power electronics. This model provides the information at the base of the design and the implementation of a dedicated low cost-high efficiency H-bridge converter for the supply of the transmitter side. A general architecture of the power electronics that manages the receiver side is proposed together with the additional protection circuits. A methodology for the integrated design of the magnetic structure is illustrated covering the aspects of the matching with the power electronics, the integration on an existing vehicle and the installation on the road infrastructure. A series of activities aimed to the implementation of a dedicated test site are presented and discussed. In particular, the activities related to the creation of the electrical infrastructure and the issues and methods for the embedding of the transmitters in the road pavement are presented. The final goal is the creation of a dedicated IPT charging line one hundred meters long. Finally, a methodology for the assessment of the human exposure is presented and applied to the developed solution

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18

Lee, Hyung-Min. "A power-efficient wireless neural stimulating system with inductive power transmission." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53449.

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The objective of the proposed research is to advance the power efficiency of wireless neural stimulating systems in inductively powered implantable medical devices (IMD). Several innovative system- and circuit-level techniques are proposed towards the development of power-management circuits and wireless neural stimulating systems with inductive power transmission to improve the overall stimulation power efficiency. Neural stimulating IMDs have been proven as effective therapies to alleviate neurological diseases, while requiring high power and performance for more efficacious treatments. Therefore, power-management circuits and neural stimulators in IMDs should have high power efficiencies to operate with smaller received power from a larger distance. Neural stimulating systems are also required to have high stimulation efficacy for activating the target tissue with a minimum amount of energy, while ensuring charge-balanced stimulation. These features provide several advantages such as a long battery life in an external power transmitter, extended-range inductive power transfer, efficacious and safe stimulation, and less tissue damage from overheating. The proposed research presents several approaches to design and implement the power-efficient wireless neural stimulating IMDs: 1) optimized power-management circuits for inductively powered biomedical microsystems, 2) a power-efficient neural stimulating system with adaptive supply control, and 3) a wireless switched-capacitor stimulation (SCS) system, which is a combination structure of the power-management circuits and neural stimulator, to maximize both stimulator efficiency (before electrodes) and stimulus efficacy (after electrodes).

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19

Goguri, Sairam. "Optimal precoder design for wireless communication and power transfer from distributed arrays." Diss., University of Iowa, 2017. https://ir.uiowa.edu/etd/6743.

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Distributed MIMO (DMIMO) communications and specifically the idea of distributed transmit beamforming involves multiple transmitters coordinating among themselves to form a virtual antenna array and steer a beam to one or more receivers. Recent works have successfully demonstrated this concept of beamforming with narrowband, frequency-flat wireless channels. We consider the generalization of this concept to wideband, frequency selective channels and propose two Figures of Merit (FOMs), namely, communication capacity and received power to measure the performance of beamforming. We formulate the precoder design that maximizes the two FOMs as optimization problems and derive general properties of the optimal precoders. The two metrics are equivalent with frequency-flat channels, whereas, they result in vastly different optimal criteria with wideband channels. The capacity maximizing solution also differs from classical water-filling due to the per-transmitter power constraints of the distributed beamforming setting, whereas, the power maximizing solution involves the array nodes concentrating their power in a small, finite set of frequencies resulting in an overall received signal consisting of a small number of sinusoidal tones. We have not been able to derive closed-form solutions for the optimal precoders, but we provide fixed point algorithms that efficiently computes these precoders numerically. We show using simulations that solution to both these maximization problems can yield substantially better performance as compared to simple alternatives such as equal power allocation. The fixed point algorithms also suggest a distributed implementation where each node can compute these precoders on their own iteratively using feedback from a cooperating receiver. We also establish the relationship between various precoders. The idea of maximizing received power suggests a natural application of wireless power transfer(WPT). However, the large-scale propagation losses associated with radiative fields makes antennas unattractive for WPT systems. Motivated by this observation, we also consider the problem of optimizing the efficiency of WPT to a receiver coil from multiple transmitters using near-field coupling. This idea of WPT using near-field coupling is not new; however, the difficulty of constructing tractable and realistic circuit models has limited the ability to accurately predicting and optimizing the performance of these systems. We present a new simple theoretical model and take the more abstract approach of modeling the WPT system as a linear circuit whose input-output relationship is expressed in terms of a small number of unknown parameters. We present a simple derivation of the optimal voltage excitations to be applied at the transmitters to maximize efficiency, and also some general properties of the optimal solution. Obviously, the optimal solution is a function of unknown parameters, and we describe a procedure to estimate these parameters using a set of direct measurements. We also present a series of experimental results, first, with two transmitter coils and a receiver coil in a variety of configurations and then with four transmitter coils and two receiver coils to illustrate our approach and the efficiency increase achieved by using the calculated optimal solution from our model.

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Sinclair, Melissa Ann. "Modeling and Design of Antennas for Loosely Coupled Links in Wireless Power Transfer Applications." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1538705/.

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Wireless power transfer (WPT) systems are important in many areas, such as medical, communication, transportation, and consumer electronics. The underlying WPT system is comprised of a transmitter (TX) and receiver (RX). For biomedical applications, such systems can be implemented on rigid or flexible substrates and can be implanted or wearable. The efficiency of a WPT system is based on power transfer efficiency (PTE). Many WPT system optimization techniques have been explored to achieve the highest PTE possible. These are based on either a figure-of-merit (FOM) approach, quality factor (Q-factor) maximization, or by sweeping values for coil geometries. Four WPT systems for biomedical applications are implemented with inductive coupling. The thesis later presents an optimization technique for finding the maximum PTE of a range of frequencies and coil shapes through frequency, geometry and shape sweeping. Five optimized TX coil designs for different operating frequencies are fabricated for three shapes: square, hexagonal, and octagonal planar-spirals. The corresponding RX is implemented on polyimide tape with ink-jet-print (IJP) silver. At 80 MHz, the maximum measured PTE achieved is 2.781% at a 10 mm distance in the air for square planar-spiral coils.

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Cordoba, Ledesma Enrique. "Analysis of effects and consequences of constructing Inductive Power Transfer Systems in road infrastructure. : A case study for the Stockholm region (Sweden)." Thesis, KTH, Transportvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-181947.

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The continuous growth in road transportation demand requires the development towards sustainable strategies. The concept of Smart Roads is arising as a convergence of technologies that will lead the mobility by road into a more efficient and interactive system between infrastructure, environment and vehicles. Within this context, e-mobility appears as one of the key components. The implementation of e-mobility based on Electric Vehicles (EVs) has been restricted by numerous shortcomings such as their driving range, the battery size, the dependence on charging stations and the time required for its charging. However, the electrification of the road infrastructure, which will enable a dynamic charging of the EVs while driving, is becoming a potential solution to overcome these deficiencies. This study aims to contribute for the future introduction of electrified roads (eRoads) into the current network, by focusing on the effects and consequences of embedding Inductive Power Transfer (IPT) systems in the road infrastructure. A structural design of an eRoad is conducted through a Finite Elements Analysis (FEA) by analysing the behaviour of a pavement structure based on Swedish conditions subjected to traffic loading. Valuable conclusions can be displayed from this analysis and thus, a summary concerning considerations and effects over the design, construction and maintenance of eRoads can be built. Nevertheless, this analysis must be complemented and coordinated from a lifetime perspective to reach the social, environmental and economic requirements related to the development of road infrastructure nowadays. Hence, a guideline from a life cycle approach is stated over the integration of eRoads in order to enable the assessment of the infrastructure during its different phases. To be sustainable, the development of road infrastructure must reach not just structural and appropriate performance requirements, but also preserve the environmental and economic impact. This thesis pretends to combine all these aspects as a state of the art, providing a basis that stands out the most relevant issues related to the feasible implementation of eRoads in the mid-long term.

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Kadem, Karim. "Modélisation et optimisation d’un coupleur magnétique pour la recharge par induction dynamique des véhicules électriques." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPAST032.

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Les travaux de recherche de cette thèse sont menés dans le cadre d’une collaboration entre le laboratoire GeePs et l’institut VEDECOM.Le coût, le volume et le poids des batteries électrochimiques représentent encore un frein important au déploiement des véhicules électriques (VE). Une des solutions envisagées pour prolonger l’autonomie des VE sans augmenter démesurément la capacité des batteries, consiste à utiliser des systèmes de transfert d’énergie électrique sans contact pour les alimenter pendant leurs déplacements. Cette thèse porte sur une de ces techniques et plus particulièrement sur le transfert d’énergie inductif résonant. Les problématiques liées à ce mode de transfert d’énergie sont principalement liées au rendement énergétique, à l’encombrement contraint du fait de la nécessité d’intégration dans le véhicule et dans la route ainsi qu'au respect des normes d’émissions électromagnétiques.L’efficacité énergétique du transfert d’énergie est au premier ordre lié au couplage des deux bobines (coupleur magnétique). Une comparaison des coefficients de couplage pour différentes géométries de coupleurs et différentes configurations de désalignement fait l’objet d’une première partie du travail réalisé. Dans la seconde partie une approche à base de sources équivalentes est proposée pour le prédimensionnement analytique d’une plaque de blindage destinée à limiter le rayonnement du coupleur dans le véhicule et en dehors de celui-ci. Dans le dernier axe de la thèse, l’étude est dédiée aux techniques de détection de la présence du véhicule et au séquencement de l’alimentation des bobines au sol. Une solution originale, permettant de répondre à cette problématique est proposée. Le bilan des travaux ainsi que les perspectives envisagées, viennent clôturer ce manuscrit
This thesis is carried out in collaboration between the GeePs laboratory and the VEDECOM institute. The cost, volume and weight of electrochemical batteries still represent a major obstacle to the deployment of electric vehicles (EVs). One of the solutions being considered to extend the range of EVs without excessively increasing the capacity of the batteries, is to use contactless electrical energy transfer systems to power them while they are on the move. This thesis focuses on one of these techniques which is the resonant inductive energy transfer. The problems associated with this mode of energy transfer are mainly related to energy efficiency, the size constrained due to the need for integration into the vehicle and the road as well as compliance with electromagnetic emissionstandards. The efficiency is directly linked to the coupling of the two coils (magnetic coupler). A comparison of the coupling coefficients for different coupler geometries and different misalignment configurations is the subject of the first part of this work. In the second part, an approach based on equivalent sources is suggested for the analytical pre-dimensioning of shielding plate intended to limit the magnetic emissions in and outside the vehicle. In the last axis of the thesis, the study is dedicated to techniques for detecting the presence of the vehicle and the sequencing of the different ground coils. A conclusion giving an assessment of the work and perspectives that open up from this work, close this manuscript

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Barbosa, Celton Ribeiro. "Estudo de sistemas de transferência indutiva de potência para recarga de baterias." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-13062018-153339/.

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A Transferência Indutiva de Potência (TIP) é uma maneira de se realizar transferência de energia elétrica sem fio e tem se popularizado atualmente por conta da comodidade e segurança que ela proporciona. Esta dissertação apresenta o estudo de um sistema TIP para recarga de baterias e existem vários desafios que devem ser superados nesta área. Um deles é a metodologia de projeto dos indutores primário e secundário, pois não é uma tarefa trivial encontrar uma relação entre parâmetros geométricos, elétricos e magnéticos. Diante deste fato este trabalho apresenta e aperfeiçoa uma metodologia de projeto utilizando uma ferramenta computacional gratuita baseada no método dos elementos finitos. Os resultados experimentais demonstram que o método é válido e a ferramenta é adequada não somente para o projeto dos indutores, mas também para análise do comportamento dos mesmos diante de desalinhamentos espaciais. Além disso, é apresentado o funcionamento básico de dois conversores muito utilizados em TIP e o estado da arte das malhas ressonantes, cuja função é minimizar a energia reativa consumida nos circuitos primário e secundário. Em seguida são discutidas técnicas de estimação de tensão e corrente na carga utilizando medidas de tensão e/ou corrente em elementos do circuito primário. Essas técnicas são importantes, pois permitem a utilização apenas do controlador presente no circuito primário e isto implica na redução dos custo e complexidade do sistema TIP. Durante o estudo verificou-se na literatura que não existia uma técnica de estimação para o sistema TIP adotado neste trabalho e portanto, foi necessário desenvolver uma nova proposta de estimador. Os resultados de simulação demonstram que o estimador possui um bom desempenho mesmo diante de variações do coeficiente de acoplamento e da resistência na carga e é portanto adequado para situações em que é necessário realizar recarga de baterias com TIP.
Inductive Power Transfer (IPT) is a way to conduct wireless power transfer and has become popular today because of the convenience and security it provides. This dissertation presents the study of a IPT system for battery recharging and there are several challenges that must be overcome in this area. One of them is the design methodology of the primary and secondary inductors, since it is not a trivial task to find a relation between geometric, electric and magnetic parameters. In view of this fact, this work presents and improves a project methodology using a free computational based on the finite element method. The experimental results demonstrate that the method is valid and the tool is suitable not only for the design of the inductors, but also for the analysis of their behavior in face of spatial misalignments. In addition, this dissertation presents the basic operation of two widely used IPT converters and the state of the art of compensations networks, whose function is to minimize the reactive energy consumed in the primary and secondary circuits. Next, load voltage and load current estimation techniques are discussed using voltage and/or current measurements on elements of the primary circuit. These techniques are important because they allow the use of a single controller in the primary circuit, reducing the cost and complexity of the IPT system. During the study, it was verified in the literature the inexistence of a estimation technique for the IPT system adopted in this work and therefore, it was necessary to propose and develop a new estimator. The simulation results show that the proposed estimator performs well even in the case of variations in the coupling coefficient and load resistance and is therefore suitable for situations where it is necessary to recharge IPT batteries.

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Moret, Alexandre Hotz. "Estudo e projeto de um sistema de transferência de energia elétrica sem fio com compensação capacitiva e baseado no transformador de bobinas em espirais planas fracamente acopladas." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-05022019-084255/.

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Recentemente os sistemas de transferência de energia sem fio WPT (do inglês Wireless Power Transfer) têm sido amplamente estudados com o propósito de alimentar eficientemente diversos tipos de cargas através de técnicas específicas, dentre elas destaca-se a transferência capacitiva de potência CPT (do inglês Capacitive Power Transfer) e a transferência indutiva de potência IPT (do inglês Inductive Power Transfer), sendo esta última objeto deste estudo. Em um sistema de transferência indutiva de potência a carga é alimentada através de um transformador fracamente acoplado. Em função do elevado espaçamento entre as bobinas primária e secundária, da ausência de núcleo magnético, ou o emprego do núcleos divididos e separados por um grande entreferro, o transformador apresenta alta reatância de dispersão e baixa reatância de magnetização, o que resulta em elevadas correntes, baixa eficiência e regulação da tensão ruim quando houver variação da carga. Com o intuito de aumentar a eficiência e melhorar a regulação de tensão (ou corrente) são aplicadas compensações capacitivas em ambos os lados do transformador, elevando o número de elementos reativos, o que dificulta a compreensão do seu comportamento. Adicionalmente, as diversas configurações geométricas possíveis para a construção das bobinas dificultam a otimização do projeto de transferência indutiva de potência. Esta dissertação analisa e compara as estratégias de compensação série-série (SS) e série-paralela (SP) sob diversos pontos de vista, identificando pontos de operação relevantes nos quais o sistema atua como uma fonte de corrente ou de tensão em malha aberta, modela os elementos que constituem um sistema de transferência indutiva de potência para alcançar à eficiência requisitada. Adicionalmente este trabalho lista os impactos na fonte e na carga quando do desvio das condições nominais de operação e dá diretrizes que permitem escolher os elementos de um sistema IPT. Na sequência esta dissertação propõe as diretrizes para a construção do transformador com valores predefinidos de fator de qualidade, indutâncias próprias e fator de acoplamento. Por fim, o presente trabalho dimensiona e confecciona alguns sistemas IPT a partir de uma lista de especificações, usando uma metodologia de projeto baseada em fórmulas aproximadas e a valida experimentalmente.
Recently Wireless Power Transfer (WPT) is widely studied in order to efficiently feed many different kinds of loads using specific techniques, such as Capacitive Power Transfer (CPT) and Inductive Power Transfer (IPT). IPT system relies on large air gap and loosely coupled transformer which will be studied in this work. Due to the large separation between the primary and secondary coils, the absence of a magnetic core, or the presence of split cores the transformer presents large leakage inductances, resulting in poor voltage regulation against load variation. Moreover, the low magnetizing inductance results in high magnetizing currents, reducing the overall efficiency. In order to improve the WPT performance, capacitive compensation techniques are applied in both sides of the transformer. Series compensation is commonly used at the primary side of the WPT transformer while Series or Parallel compensation is eligible to the secondary side. In addition, the loosely coupled transformer must be designed, in spite of the complex relationship between the various electrical and geometrical parameters of the coils that complicates the transformer construction and its optimization. This work compares Series-Series and Series-Parallel compensation strategies based on a simple approach, comprehensively highlighting the pro and cons of each one. Also the open loop operation in voltage source and current source modes, and the effect of the gap length for both compensation strategies are discussed. Moreover, the elements that constitute an inductive power transfer system are modeled in order to achieve the required efficiency. This research also proposes some guidance to build the transformer with high figure-of-merit and coupling. Finally, the present work designs and builds few IPT systems that satisfies a set of specifications, based on a simplified design procedure. The proposed design methodology is experimentally validated.

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Mohammad, Mostak. "Optimization of Inductive Wireless Charging Systems for Electric Vehicles: Minimizing Magnetic Losses and Limiting Electromagnetic Field Emissions." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1564756659521461.

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Fernandes, Rodolfo Castanho. "Elementos magnéticos fracamente acoplados para aplicação em transferência indutiva de potência: procedimento e critérios de projeto, análise de sensibilidade e condições de bifurcação." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-28092015-164437/.

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Além da transferência de energia elétrica por meio de condutores sólidos que interligam carga e fonte elétrica, existem formas alternativas que, por não necessitarem de conexão mecânica, permitem maior mobilidade espacial para a carga e trazem inúmeras novas possibilidades de aplicação. Dentre estas formas alternativas está a Transferência Indutiva de Potência, que possui desafios claros no que diz respeito ao projeto do sistema magnético formado pelos indutores emissor e receptor, quando entre eles existe acoplamento magnético muito reduzido. A retirada do núcleo magnético sólido entre emissor e receptor confere a possibilidade de o receptor se mover em relação ao emissor, o que permite a transferência de potência a uma carga móvel. Contudo, o baixo coeficiente de acoplamento magnético torna o sistema fracamente acoplado sensível a variações tanto no circuito ressonante que o alimenta quanto na própria geometria magnética, onde pequenas modificações dimensionais resultam em significativos ganhos de potência no receptor. Esta tese apresenta inicialmente um conjunto de rotinas computacionais que agilizam o projeto de sistemas fracamente acoplados contendo emissores e receptores circulares ou espirais. Estas rotinas agem como pré e pós-processadores do Método dos Elementos Finitos, que por sua vez é solucionado por um aplicativo bidimensional gratuito. Com esta abordagem, é possível desenvolver rapidamente acopladores magnéticos com parâmetros realísticos, cuja montagem experimental demonstra excelente conformidade com os resultados teóricos. Um grupo de onze acopladores magnéticos diferentes é avaliado nesta tese como demonstração de que a otimização de parâmetros geométricos é relevante para a maximização de potência no receptor. Compara-se também o desempenho de acopladores Bipolar, Duplo D e Duplo D Quadratura. Após evidenciar relações geométricas e magnéticas para os diversos acopladores, verifica-se por meio de estudos de sensibilidade paramétrica, que não apenas a geometria do sistema fracamente acoplado influencia em seu desempenho, mas também a escolha dos parâmetros das malhas ressonantes conectadas ao emissor e ao receptor. Disto se conclui sobre a importância da Análise de Sensibilidade em Transferência Indutiva de Potência, pois, como demonstrado, certas malhas ressonantes são naturalmente mais tolerantes a variações do coeficiente de acoplamento magnético do que outras, por exemplo, aquelas em que há compensação do tipo paralelo no emissor. Por fim, o trabalho dedica-se ao estabelecimento de critérios para a ocorrência do fenômeno de bifurcação, segundo o qual múltiplas frequências de ressonância podem ocorrem em um conversor em frequência variável, a depender da carga conectada ao receptor e dos fatores de qualidade dos indutores. O equacionamento, obtido numericamente e que foi generalizado para casos em que existem múltiplos receptores, permite boa previsibilidade a respeito do comportamento dinâmico de sistemas variáveis em frequência.
In addition to the transfer of electrical energy by means of solid conductors that interconnect electrical source and load, there are alternative ways that does not require mechanical connection and allow spatial mobility to the load bringing numerous new application possibilities. Among these alternative forms is Inductive Power Transfer, which has clear challenges with respect to the magnetic system design formed by emitter and receiver inductors, since there is very little magnetic coupling between them. The removal of the solid magnetic core between emitter and receiver introduces the possibility of moving receivers. However, the low magnetic coupling coefficient makes the loosely coupled system sensitive to variations in both the resonant circuit parameters and the magnetic geometry, where small dimensional changes result in significant power gains in the receiver. This thesis initially presents a set of computing routines that allows the design of loosely coupled systems containing circular or spiral inductors. These routines act as pre- and post-processors for Finite Element Method, which in turn is solved by a free two-dimensional application. With this approach one can quickly develop magnetic couplers with realistic parameters, which is demonstrated by comparison between experimental and theoretical results. A group of eleven different magnetic couplers is evaluated as a proof that the optimization of geometric parameters is relevant to maximizing the power of the receiver. Moreover, the performance of Bipolar, Double D and Double D Quadrature couplers are studied. Later, it is verified by means of parametric sensitivity analysis that not only the geometry of the loosely coupled system influences its performance, but also the choice of the parameters of the resonant converters connected to emitter and receiver. The sensitivity analysis of Inductive Power Transfer converters was found to be of great importance because, as shown by a numerical example, certain resonant topologies can be naturally more tolerant to variations in the magnetic coupling coefficient than others. Finally, the work is dedicated to the establishment of precise criteria for the occurrence of bifurcation phenomenon whereby multiple resonant frequencies can occur in a converter under variable frequency excitation, depending on the load connected to the receiver and the quality factors of inductors. The equations obtained numerically were generalized for cases where there are multiple receivers and allow good predictability about the dynamic behavior of variable frequency systems.

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Lazaro, Orlando. "CMOS inductively coupled power receiver for wireless microsensors." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51874.

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This research investigates how to draw energy from a distant emanating and alternating (i.e., AC) magnetic source and deliver it to a battery (i.e., DC). The objective is to develop, design, simulate, build, test, and evaluate a CMOS charger integrated circuit (IC) that wirelessly charges the battery of a microsystem. A fundamental challenge here is that a tiny receiver coil only produces mV's of AC voltage, which is difficult to convert into DC form. Although LC-boosted diode-bridge rectifiers in the literature today extract energy from similar AC sources, they can do so only when AC voltages are higher than what miniaturized coils can produce, unless tuned off-chip capacitors are available, which counters the aim of integration. Therefore, rather than rectify the AC voltage, this research proposes to rectify the current that the AC voltage induces in the coil. This way, the system can still draw power from voltages that fall below the inherent threshold limit of diode-bridge rectifiers. Still, output power is low because, with these low currents, small coils can only extract a diminutive fraction of the magnetic energy available, which is why investing battery energy is also part of this research. Ultimately, the significance of increasing the power that miniaturized platforms can output is higher integration and functionality of micro-devices, like wireless microsensors and biomedical implants.

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Azambuja, Ricardo de. "Avanços no desempenho de circuitos acoplados indutivamente com compensação capacitiva e ajuste de frequência." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/75711.

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Neste trabalho, é apresentado um estudo sobre sistemas de transmissão de energia com o uso de bobinas fracamente acopladas magneticamente. A análise é feita levando-se em conta os efeitos parasitas dos componentes em um circuito equivalente considerando-se somente uma única frequência e o circuito já no regime estacionário. Esse circuito é alimentado por uma fonte de tensão senoidal e conectado a uma carga puramente resistiva por simplificação. São analisadas a potência de saída e a eficiência do circuito. Portanto um exercício de otimização dessas duas variáveis é desenvolvido ao longo desse trabalho com diferentes possíveis configurações. Um novo método de compensação do circuito utilizando quatro capacitores é apresentado. Além disso, é explorada a possibilidade de se melhorar ainda mais o resultado da compensação através do ajuste da frequência de ressonância. Inicialmente, o circuito básico sem compensação é analisado. A seguir, são desenvolvidas equações para as máximas eficiência e potência na saída para os circuitos contendo somente um capacitor de compensação. Também são demonstradas as configurações normalmente utilizadas para compensação com dois capacitores. Então a compensação de um circuito com quatro capacitores sem perdas é analisada. Finalmente, após serem adicionadas todas as perdas resistivas dos componentes do circuito, um método de busca é empregado para encontrar os valores ótimos (ou subótimos) dos capacitores que fazem o circuito alcançar a máxima eficiência ou potência na saída. Um algoritmo baseado no método Monte Carlo é apresentado de modo a obter boas soluções para o problema de otimização proposto e assim evitar a análise direta do intrincado sistema de equações resultantes da compensação com mais do que dois capacitores. Para verificar experimentalmente os resultados teóricos e das simulações foi construído um protótipo que possibilita uma variação linear e de maneira controlada do coeficiente de acoplamento entre as bobinas. Os resultados são comparados e, ainda, melhorados através do método da sintonia da frequência.
In this work, we present a study of power transmission systems using magnetically loosely coupled coils. The analysis is done taking into account the effects of parasitic components in an equivalent circuit considering only a single frequency and the circuit already in the steady state. This circuit is powered by a sinusoidal voltage source and connected to a purely resistive load for simplification. Improvements in the output power and efficiency of the circuit are the main topic. So an exercise in optimization of these two variables is developed throughout this work with different possible configurations. A new compensation method using four capacitors of the circuit is presented. Moreover, the possibility is exploited to further improve the result of compensation by adjusting the resonance frequency. Initially, the basic circuit without compensation is analyzed. The following equations are designed for maximum efficiency and output power for the circuits containing only one compensation capacitor. Also, the settings normally used to offset two capacitors are presented. So the compensation of a circuit with four capacitors lossless is analyzed. Finally, are added all the resistive losses of the circuit components, an search method is employed to find the optimal values (or suboptimal) capacitors that make the circuit to achieve maximum efficiency or power output. An algorithm based on Monte Carlo method is presented to solve the proposed optimization problem and thus avoid direct analysis of the intricate system of equations resulting from the clearing of more than two capacitors. To experimentally verify the theoretical results of simulations a prototype was constructed which allows for linear variation and a controlled coefficient of coupling between the coils. The results are compared and, moreover, improved by the method of tuning the frequency.

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Vigneau, Guillaume. "Etude et modélisation d’un système de transmission d’énergie et de données par couplage inductif pour des systèmes électroniques dans l’environnement automobile." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30281.

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Actuellement, les systèmes permettant de transférer de l’énergie dans le but de recharger les accumulateurs d’appareils électroniques sans l’emploi de câble se démocratisent davantage chaque jour. On comprend donc bien l’intérêt de tels systèmes dans des environnements embarqués et confinés tels que l’habitacle d’un véhicule. Le principe de l’induction magnétique réside dans un transfert de flux magnétique entre deux antennes inductives. Le champ magnétique servira de vecteur au transport d’une puissance électrique, puisque c’est au travers de cette création de flux magnétique que sera échangée ou transférée la puissance d’un émetteur vers un récepteur. Un tel système d’émission-réception de puissance utilisant le principe d’induction magnétique contient un émetteur, des antennes (bobines) inductives couplées et un récepteur. Un premier chapitre sera donc consacré à l’étude des antennes d’un point de vue théorique et technologique. Des modèles électromagnétiques d’antennes inductives seront développés, et après validation par corrélation avec des mesures électriques et électromagnétiques, ils seront employés au travers d’intenses simulations électromagnétiques. Ceci afin de montrer l’impact des paramètres définissant ces antennes inductives sur leurs comportements électrique et électromagnétique. Une fois les antennes inductives optimisées et leurs paramètres clés identifiés, on étudiera dans un deuxième temps les effets de l’induction magnétique lorsque qu’une antenne d’émission et une autre de réception sont présentées ensembles et mises en condition de transfert d’énergie. On mettra donc en évidence le principe de couplage magnétique entre les antennes ainsi que la notion de rendement de puissance appelé aussi efficacité de liaison. Les différents paramètres des antennes seront là aussi caractérisés afin d‘étudier leur influence sur le transfert d’énergie inductif. Le tout illustré de la même manière que précédemment, en s’appuyant sur d’intenses simulations électromagnétiques et des modèles validés par rapport à différentes méthodes de mesure. Ceci dans le but de comprendre les mécanismes de fonctionnement et d’optimisation d’un système de transfert d’énergie par induction magnétique ainsi que de proposer des règles générales de conception d’antennes inductives. Dans un troisième temps, on présentera les différents étages électroniques composant les systèmes de transfert d’énergie inductif. Une partie sera dédiée à la définition du point de vue système des éléments constituant la chaine complète d’émission et de réception. La conception, l’optimisation et la mesure des amplificateurs de puissance utilisés au niveau de l’émetteur seront également présentés. En effet, ces systèmes doivent être suffisamment performants afin de transférer des puissances capables d’alimenter des appareils électroniques de type téléphones tout en ayant un bilan de puissance efficace avec des pertes limitées. A partir de modèles de circuits émetteur et récepteur et en s’appuyant sur des simulations circuits, nous estimerons les bilans de puissances afin d’évaluer les performances et les limites des différents systèmes. Ces simulations une fois validées par mesures permettront de quantifier l’efficacité du transfert de puissance et proposer des voies d’optimisation. Ces systèmes et technologies sont de plus en plus utilisés pour l’électronique grand public et il existe actuellement plusieurs standards régissant le transfert d’énergie inductif. Les différentes études présentées dans cette thèse seront donc orientées vers ces différentes normes, et des analogies seront réalisées tout le long du mémoire afin de mettre en exergue leurs différents principes de fonctionnement
Nowadays there is a strong demand of systems allowing to transfer energy in a wirelessly way to small electronic devices. So we can well understand the interest of such systems in embedded environments such as vehicle cockpit. The principle of magnetic induction comes from a magnetic flux exchange between two inductive antennas. The magnetic field will be used to transport an electrical power from an emitter to a receiver. These systems using the magnetic induction to transfer energy contain an emitter, inductive antennas (coils) and a receiver. A first chapter will be dedicated to the antennas employed in inductive wireless power transfer systems on theoretical and technological points of views. An electromagnetic modeling of these inductive antennas will be realized and validated through correlation with measurements. Once the modeling process defined and the validations done, it will be used through intensive electromagnetic simulations in order to show the impact of antennas parameters on their electrical and electromagnetic performances. After the inductive antennas characterization and their key parameters identification done, we will study in a second time the magnetic induction effects when emission and reception antennas are placed together in order to realize an inductive power transfer. Notions of magnetic coupling which appears between inductive antennas and magnetic efficiency which characterizes how much quantities of power are transferred will be highlighted. In the same conditions as before, the impact of antennas parameters on the power transfer and magnetic coupling will be investigated through electromagnetic modeling of inductive antennas and the use of intensive electromagnetic simulations. Thus, we will have the opportunity to precisely understand the meaning of the inductive power transfer and the different ways of optimizations. By this way, we will also propose some general design guidelines for antennas employed in inductive wireless power transfer systems. A third chapter will be dedicated to the presentation of the different electronic stages used in inductive wireless power transfer systems. A part of it will be employed on the definitions of the different elements allowing the wireless power transfer on a system approach. The design, optimization and measurement of power amplifiers used on the emission stage will be presented too.. Indeed, it is necessary to have efficient power amplification in order to transfer the required power to different receivers such as phones at the same time to limit the power losses. From circuit modeling of different emitter and receiver and with circuit simulations, we will develop power budgets in order to evaluate the performances and limits of these systems. Once the simulation validated by measurement, we will be able to quantify the total power transfer efficiency and propose optimization ways. Because of the current existence of different inductive wireless power standards on the industrial market for electronic consumer, analogies with them will be done all along the different steps of this thesis in order to highlighted their different functioning principles

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Vogt, Johannes Paul, and Jana Kertzscher. "Induktives Ladesystem für den Einsatz in autonomen Verleihstationen." TU Bergakademie Freiberg, 2019. https://tubaf.qucosa.de/id/qucosa%3A38461.

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Der vorliegende Beitrag beschreibt das Konzept eines induktiven Ladesystems für autonome Verleihstationen. Unter Beachtung der Betriebsanforderungen wird im ersten Teil eine zweckmäßige Spezifikation des Ladesystems erarbeitet. Der zweite Teil beschreibt die Modellierung des Resonanzübertragers, welcher technisch als Prototyp realisiert wurde. Dazu erfolgt die analytische Berechnung der Parameter und Vergleich mit den experimentell bestimmten Parametern am Prototypen.
This article describes the concept of an inductive charging system for autonomous sharing stations. In accordance with the operational requirements, a suitable specification of the charging system is developed in the first part of this paper. The second part describes the modelling of the resonant transmitter, which was technically realized as a prototype. For this purpose, the analytical calculation of the parameters and their comparison with the experimentally determined parameters on the presented prototype are carried out.

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Abdelhameed, Mohamed Ahmed Saad. "On-chip adaptive power management for WPT-Enabled IoT." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/587158.

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Internet of Things (IoT), as broadband network connecting every physical objects, is becoming more widely available in various industrial, medical, home and automotive applications. In such network, the physical devices, vehicles, medical assistance, and home appliances among others are supposed to be embedded by sensors, actuators, radio frequency (RF) antennas, memory, and microprocessors, such that these devices are able to exchange data and connect with other devices in the network. Among other IoT’s pillars, wireless sensor network (WSN) is one of the main parts comprising massive clusters of spatially distributed sensor nodes dedicated for sensing and monitoring environmental conditions. The lifetime of a WSN is greatly dependent on the lifetime of the small sensor nodes, which, in turn, is primarily dependent on energy availability within every sensor node. Predominantly, the main energy source for a sensor node is supplied by a small battery attached to it. In a large WSN with massive number of deployed sensor nodes, it becomes a challenge to replace the batteries of every single sensor node especially for sensor nodes deployed in harsh environments. Consequently, powering the sensor nodes becomes a key limiting issue, which poses important challenges for their practicality and cost. Therefore, in this thesis we propose enabling WSN, as the main pillar of IoT, by means of resonant inductive coupling (RIC) wireless power transfer (WPT). In order to enable efficient energy delivery at higher range, high quality factor RIC-WPT system is required in order to boost the magnetic flux generated at the transmitting coil. However, an adaptive front-end is essential for self-tuning the resonant tank against any mismatch in the components values, distance variation, and interference from close metallic objects. Consequently, the purpose of the thesis is to develop and design an adaptive efficient switch-mode front-end for self-tuning in WPT receivers in multiple receiver system. The thesis start by giving background about the IoT system and the technical bottleneck followed by the problem statement and thesis scope. Then, Chapter 2 provides detailed backgrounds about the RIC-WPT system. Specifically, Chapter 2 analyzes the characteristics of different compensation topologies in RIC-WPT followed by the implications of mistuning on efficiency and power transfer capability. Chapter 3 discusses the concept of switch-mode gyrators as a potential candidate for generic variable reactive element synthesis while different potential applications and design cases are provided. Chapter 4 proposes two different self-tuning control for WPT receivers that utilize switch-mode gyrators as variable reactive element synthesis. The performance aspects of control approaches are discussed and evaluated as well in Chapter 4. The development and exploration of more compact front-end for self-tuned WPT receiver is investigated in Chapter 5 by proposing a phase-controlled switched inductor converter. The operation and design details of different switch-mode phase-controlled topologies are given and evaluated in the same chapter. Finally, Chapter 6 provides the conclusions and highlight the contribution of the thesis, in addition to suggesting the related future research topics.
Internet de las cosas (IoT), como red de banda ancha que interconecta cualquier cosa, se está estableciendo como una tecnología valiosa en varias aplicaciones industriales, médicas, domóticas y en el sector del automóvil. En dicha red, los dispositivos físicos, los vehículos, los sistemas de asistencia médica y los electrodomésticos, entre otros, incluyen sensores, actuadores, subsistemas de comunicación, memoria y microprocesadores, de modo que son capaces de intercambiar datos e interconectarse con otros elementos de la red. Entre otros pilares que posibilitan IoT, la red de sensores inalámbricos (WSN), que es una de las partes cruciales del sistema, está formada por un conjunto masivo de nodos de sensado distribuidos espacialmente, y dedicados a sensar y monitorizar las condiciones del contexto de las cosas interconectadas. El tiempo de vida útil de una red WSN depende estrechamente del tiempo de vida de los pequeños nodos sensores, los cuales, a su vez, dependen primordialmente de la disponibilidad de energía en cada nodo sensor. La fuente principal de energía para un nodo sensor suele ser una pequeña batería integrada en él. En una red WSN con muchos nodos y con una alta densidad, es un desafío el reemplazar las baterías de cada nodo sensor, especialmente en entornos hostiles, como puedan ser en escenarios de Industria 4.0. En consecuencia, la alimentación de los nodos sensores constituye uno de los cuellos de botella que limitan un despliegue masivo práctico y de bajo coste. A tenor de estas circunstancias, en esta tesis doctoral se propone habilitar las redes WSN, como pilar principal de sistemas IoT, mediante sistemas de transferencia inalámbrica de energía (WPT) basados en acoplamiento inductivo resonante (RIC). Con objeto de posibilitar el suministro eficiente de energía a mayores distancias, deben aumentarse los factores de calidad de los elementos inductivos resonantes del sistema RIC-WPT, especialmente con el propósito de aumentar el flujo magnético generado por el inductor transmisor de energía y su acoplamiento resonante en recepción. Sin embargo, dotar al cabezal electrónico que gestiona y condicionada el flujo de energía de capacidad adaptativa es esencial para conseguir la autosintonía automática del sistema acoplado y resonante RIC-WPT, que es muy propenso a la desintonía ante desajustes en los parámetros nominales de los componentes, variaciones de distancia entre transmisor y receptores, así como debido a la interferencia de objetos metálicos. Es por tanto el objetivo central de esta tesis doctoral el concebir, proponer, diseñar y validar un sistema de WPT para múltiples receptores que incluya funciones adaptativas de autosintonía mediante circuitos conmutados de alto rendimiento energético, y susceptible de ser integrado en un chip para el condicionamiento de energía en cada receptor de forma miniaturizada y desplegable de forma masiva. La tesis empieza proporcionando una revisión del estado del arte en sistemas de IoT destacando el reto tecnológico de la alimentación energética de los nodos sensores distribuidos y planteando así el foco de la tesis doctoral. El capítulo 2 sigue con una revisión crítica del statu quo de los sistemas de transferencia inalámbrica de energía RIC-WPT. Específicamente, el capítulo 2 analiza las características de diferentes estructuras circuitales de compensación en RIC-WPT seguido de una descripción crítica de las implicaciones de la desintonía en la eficiencia y la capacidad de transferencia energética del sistema. El capítulo 3 propone y explora el concepto de utilizar circuitos conmutados con función de girador como potenciales candidatos para la síntesis de propósito general de elementos reactivos variables sintonizables electrónicamente, incluyendo varias aplicaciones y casos de uso. El capítulo 4 propone dos alternativas para métodos y circuitos de control para la autosintonía de receptores de energía

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Pavlyuk, Yuri. "Application of static transfer switch for induction motor load transfer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0022/MQ51612.pdf.

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Anele, Amos onyedikachi. "Conception et l'amélioration de la structure de couplage magnétique pour des systèmes de transfert de puissance inductive localisées." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV038/document.

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Compte tenu du contexte économique du marché des hydrocarbures et les problématiques environnementales, le développement des véhicules électriques (VE) prend de l’ampleur car ils sont considérés comme plus écologiques. Aujourd’hui, les véhicules électriques sont considérés comme une solution favorable pour une énergie plus verte. L'électricité qu'ils consomment peut être générée à partir d'un large éventail de sources qui comprennent les combustibles fossiles, l'énergie nucléaire et les énergies renouvelables. Toutefois, les utilisateurs et les propriétaires de véhicules électriques ont encore des réticences car cela nécessite un stockage d'énergie électrique à bord pour assurer une bonne autonomie.Le système de transfert de puissance par effet inductif (LIPT en anglais) est une nouvelle technologie qui permet le transfert d'énergie électrique par champ magnétique et un système de bobines primaires et secondaires. Le champ magnétique est un champ haute-fréquence à plusieurs dizaines de kilohertz. Par rapport au système de câble conventionnel, le système LIPT est capable de fournir une recharge qui est pratique mais également efficace des véhicules électriques. Cependant, actuellement son principal facteur limitant est la mauvaise performance de sa structure de couplage magnétique (MCS). L’objectif de cette thèse est d'améliorer la performance des systèmes MCS pour les systèmes de LIPT afin de concevoir des systèmes à meilleur rendement.Dans un premier temps, sur la base de modèles mathématiques issus de la littérature, un code Matlab a été mis en œuvre pour calculer l'inductance mutuelle des systèmes de bobines mise en jeu dans le MCS. Puis, le calcul et la validation expérimentale des champs magnétiques entre le primaire et le secondaire a été effectué.Dans un second temps, un modèle d'un système LIPT pour la charge d’une batterie de véhicule électrique est présenté. Sur la base des spécifications techniques d’une Renault ZOE, les résultats obtenus montrent que, en adaptant la fréquence de la bobine primaire et en compensant avec un système série-série de condensateurs, un système à 3 kW et un système à 22 kW peuvent atteindre des performances permettant la recharge d’une Renault Zoe dans de bonnes conditions.Enfin, une analyse par éléments finis (FEA) sous COMSOL est développée pour la conception, le calcul et l’optimisation de systèmes MCS plus complexes de nouveaux LIPT. Les modèles de MCS conçus intègrent des bobines d'air évidées avec des configurations appropriées de noyaux magnétiques (par exemple en ferrite), avec des études également sur des parties couvrantes des bobines primaires et secondaires en acier. Les performances des modèles conçus sont déterminées par les valeurs de l'inductance mutuelle et la tension induite qui sont deux critères d’évaluations
Taking into account high oil prices and environmental awareness, the development of electric vehicles (EVs) is considered as a healthier mode of transportation. Amongst other eco-friendly vehicles, EVs are considered as a favourable solution for a greener energy because the electricity they consume can be generated from a wide range of sources which include fossil fuel, nuclear power and renewable energy. However, users and owners of EVs feel uncomfortable because EVs require sufficient electrical energy battery storage on-board to provide sufficient driving autonomy.Lumped inductive power transfer (LIPT) system is a new technology that allows the transfer of electric power between its air-cored primary and secondary coils via high frequency magnetic fields to a consuming device. Unlike the conventional plug-in system, LIPT system is capable of providing a safe, efficient and convenient overnight recharging of EVs. However, its main limiting factor is the poor performance of its magnetic coupling structure (MCS), which is intended to transfer power efficiently. Thus the problem statement of this thesis is to improve the performance of MCS models for LIPT systems.Firstly, based on a more efficient and relevant mathematical model available in the literature, MATLAB code is implemented to compute the mutual inductance between air-cored filamentary circular (FC) coils. Also, the computation and experimental validation of the magnetic fields between two FC coils are presented.Furthermore, computational models of an IPT system for EV battery charge are presented in this thesis. Based on the technical specifications of Renault ZOE, the results obtained show that by supplying a higher frequency AC voltage to the primary coil of the MCS and compensating the primary and secondary sides of the air-cored coils with series-series capacitors, the 3 kW single-phase and 22 kW three-phase IPT systems modelled using MATLAB/Simulink are capable of delivering the electricity needed to power the Renault ZOE.Finally, in order to recommend a suitable and cost-efficient MCS model that can help transfer electric power more efficiently for the battery charging of EVs and E-bikes, a 3-D finite element analysis (FEA) package called COMSOL multiphysics is used to design, compute and investigate a more complex and realistic MCS model of LIPT systems. The designed MCS models incorporate air-cored coils with proper configuration of magnetic cores (e.g. ferrite), structural steel covering for the bottom part of the primary coil and top part of the secondary coil and lastly, iron plate which serves as a covering for the primary coil installed underground and the chassis or underbody structure of EVs. The performance of the designed models are determined by the values of the mutual inductance and induced voltage obtained from COMSOL

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Jackson, Deron K. (Deron Keith). "Inductively-coupled power transfer for electromechanical systems." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9956.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.
Includes bibliographical references (p. 359-366).
by Deron Keith Jackson.
Ph.D.

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Shah, Raza. "Property inference decision-making and decision switching of undergraduate engineers : implications for ideational diversity & fluency through movements in a Cartesian concept design space." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/278700.

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Design fixation is a phenomenon experienced by professional designers and engineering design students that stifles creativity and innovation through discouraging ideational productivity, fluency and diversity. During the design idea and concept generation phase of the design process, a reliance on perceptual surface feature similarities between design artefacts increases the likelihood of design fixation leading to design duplication. Psychologists, educators and designers have become increasingly interested in creative idea generation processes that encourage innovation and entrepreneurial outcomes. However, there is a notable lack of collaborative research between psychology, education and engineering design particularly on inductive reasoning of undergraduate engineering students in higher education. The data gathered and analysed for this study provides an insight into property inference decision-making preferences and decision switching (SWITCH) patterns of engineering undergraduates under similarity-based inductive judgements [SIM] and category-based inductive judgements [CAT]. For this psychology experiment, property induction tasks were devised using abstract shapes in a triad configuration. Participants (N = 180), on an undergraduate engineering programme in London, observed a triad of shapes with a target shape more similar-looking to one of two given shapes. Factors manipulated for this experiment included category alignment, category group, property type and target shape. Despite the cognitive development and maturation stage of undergraduate engineers (adults) in higher education, this study identified similarity-based inductive judgements [SIM] to play a significant role during inductive reasoning relative to the strength of category-based inductive judgements [CAT]. In addition to revealing the property inference decision-making preferences of a sample of undergraduate engineers (N = 180), two types of switch classification and two types of non-switch classification (SWITCH) were found and named SIM_NCC, SIM-Salient, Reverse_CAT and CAT_Switching. These different classifications for property inference switching and non-switching presented a more complex pattern of decision-making driven by the relative strength between similarity-based inductive judgements [SIM] and category-based inductive judgements [CAT]. The conditions that encouraged CAT_Switching is of particular interest to design because it corresponds to inference decision switching that affirms the sharing of properties between dissimilar-looking shapes designated as category members, i.e., in a conflicting category alignment condition (CoC). For CAT_Switching, this study found a significant interaction between a particular set of conditions that significantly increased the likelihood of property inference decisions switching to affirm the sharing of properties between dissimilar-looking shapes. Stimuli conditions that combined a conflicting category alignment condition (where dissimilar-looking shapes belong to the same category) with category specificity, a causal property and a target shape with merged (or blended) perceptual surface features significantly increased the likelihood of a property inference decision switching. CAT_Switching has important implications for greater ideational productivity, fluency and diversity to discourage design fixation within the conceptual design space. CAT_Switching conditions could encourage more creative design transformations with alternative design functions through inductive inferences that generalise between dissimilar artefact designs. The findings from this study led to proposing a Cartesian view of the concept design space to represent the possibilities for greater movements through flexible and expanding category boundaries to encourage conceptual combinations, greater ideational fluency and greater ideational diversity within a configuration design space. This study has also created a platform for further research into property inference decision-making, ideational diversity and category boundary flexibility under stimuli conditions that encourage designers and design students to make inductive generalisations between dissimilar domains of knowledge through a greater emphasis on causal relations and semantic networks.

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Fernandes, Ricardo Dias. "Resonant wireless power transmission based on resonant electrical coupling." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16284.

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Doutoramento em Engenharia Eletrotécnica
Contained in this document are theoretical and experimental results related to the feasibility of resonant electrical coupling as a method of wirelessly transferring power across non-negligible distances. As shown, resonant electrical coupling is remarkably similar to resonant magnetic coupling in several aspects. However, while resonant magnetic coupling is currently a method of wirelessly transferring power with a very strong presence in the literature, resonant electrical coupling is not. The lack of material related to resonant electrical coupling, together with the potential of achieving a balanced trade-off between critical features such as efficiency, distance, simplicity, size and power transfer capability, were the main motivations for considering this specific topic. The possibility of constructively combining resonant electrical coupling and resonant magnetic coupling is also addressed. A review of the state of the art of wireless power, not only in terms of scientific publications but also in terms of market adoption and international standards, is included in this document.
Contidos neste documento estão resultados teóricos e experimentais relacionados com a viabilidade do uso de acoplamento elétrico ressonante como um método de transferência de energia sem fios através de distâncias não negligenciáveis. Conforme mostrado, o acoplamento elétrico ressonante é notavelmente semelhante ao acoplamento magnético ressonante em vários aspetos. No entanto, enquanto que o acoplamento magnético ressonante é atualmente um método de transferência de energia sem fios com uma presença muito forte na literatura, o acoplamento elétrico ressonante não é. A ausência de material relacionado com acoplamento elétrico ressonante, em conjunto com o potencial de atingir um compromisso equilibrado entre características críticas, tais como eficiência, distância, simplicidade, tamanho e capacidade de transferência de potência, foram as principais motivações para considerar este tóptico específico. A possibilidade de combinar de forma construtiva acoplamento elétrico ressonante e acoplamento magnético ressonante é também abordada. Uma revisão do estado da arte da transferência de energia sem fios, não só em termos de publicações científicas, mas também em termos de adoção do mercado e normas internacionais, é incluída neste documento.

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Bednařík, Josef. "Návrh a realizace bezdrátového nabíjení pro vestavěné systémy." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417755.

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This thesis deals with the design and realization of wireless power charging circuit for embedded systems. The research section focuses on the various ways and technologies used in applications of wireless power transfer. The theoretical part also briefly characterizes resonant inductive coupling and critical parameters of the transfer. This is followed by realization of various variants of transfer coils and electromagnetic oscillators. Wireless power charging prototype system is created and used for testing purposes to find optimal configuration of resonator. The hardware unit presented in the final part of the thesis exploits microcontroller and implemented software is extended by foreign object detection algorithm along with method to monitor battery charging state.

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Barba, Rossa Guillaume. "Modélisation multiphysique de l'élaboration de verre en creuset froid." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI050/document.

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La vitrification des déchets radioactifs de haute activité et vie longue permet d'assurer leur confinement à long terme grâce à l'intégration à l'échelle atomique des radioisotopes au sein d'une matrice vitreuse. Parmi les différents procédés de vitrification, celui basé sur l'utilisation d'un creuset froid à induction électromagnétique directe présente de nombreux avantages. Il est à ce titre en fonctionnement depuis 2010 à l'usine française de retraitement de la Hague. Affiner la compréhension et la modélisation des phénomènes en jeu dans un creuset froid lors de l'élaboration de verre constitue un enjeu décisif pour le soutien industriel et l'appui des démarches d'optimisation du procédé. Dans cette optique, nos travaux proposent un modèle multiphysique ainsi qu'une simulation numérique prédictive prenant en compte l'ensemble des phénomènes couplés régissant le comportement de la charge de verre lors de son élaboration en creuset froid, en termes de convection, de flux thermiques et d'interactions électromagnétiques. Dans un premier temps sont formulées les hypothèses de travail permettant la modélisation mathématique du système magnéto-thermo-hydraulique avec un degré d'approximation contrôlé. Nous mettons notamment en place une approche multi-échelle pour la prise en compte de la nature diphasique du verre nucléaire, constitué d'une matrice homogène présentant des particules métalliques micrométriques de platinoïdes en suspension. La résolution numérique du modèle couplé est alors assurée par le développement et l'utilisation de codes de simulation précis, stables et optimisés, en proposant des schémas numériques et des méthodes de couplage adaptés. Une grande part de nos travaux est dédiée à l'analyse des phénomènes physiques caractéristiques de la fusion du verre, liés de manière générale aux propriétés physico-chimiques variables du matériau (viscosité, masse volumique, conductivité électrique...). Sont notamment étudiés deux grands axes qui constituent des apports applicatifs importants : le transport, la réponse à l'induction et la sédimentation des particules de platinoïdes ainsi que les échanges thermiques entre le verre en fusion et les parois refroidies du creuset. Des lois d'échelle pour l'évaluation de l'intensité respective de ces phénomènes sont dérivées de l'analyse du modèle couplé. Enfin, des comparaisons expérimentales précises, à la fois à petite échelle et à l'échelle industrielle, permettent de valider l'approche choisie et les résultats obtenus
The vitrification of high-level nuclear waste ensures their long-term confinement through atomic integration of radioisotopes within a vitreous matrix. Among the various vitrification processes, the one based on the use of a cold crucible with direct electromagnetic induction shows many advantages. Thus it has been in operation since 2010 at the French reprocessing plant at La Hague. Refining the understanding and the modeling of the phenomena involved during glass melting inside a cold crucible constitutes a decisive stake for industrial support and process optimization. In this context, our work presents a multiphysics model as well as a predictive numerical simulation taking into account all the coupled phenomena governing the behavior of the glass melt, in terms of convection, heat fluxes and electromagnetic interactions. The working hypotheses are first formulated, allowing the mathematical modeling of the magneto-thermo-hydraulic system with a controlled degree of approximation. In particular, we design a multi-scale approach to take into account the diphasic nature of nuclear glass, consisting of a homogeneous matrix seeded with micrometric particles mostly made of platinum-group metals. The numerical resolution of the coupled model is then assured by the development and use of precise, stable and optimized simulation codes, by proposing numerical schemes and adapted coupling methods. A large part of our work is dedicated to the analysis of the physical phenomena characteristic of glass melting, generally related to the variable physicochemical properties of the material (viscosity, density, electrical conductivity...). In particular, two main axes are studied here with important applications: transport, response to the induction and settling of the platinum-group metal particles and heat transfers between the molten glass and the cooled walls of the crucible. Scaling laws for the evaluation of the respective intensity of these phenomena are derived from the coupled model analysis. Finally, precise experimental comparisons, both on a small scale and on an industrial scale, make it possible to validate the chosen approach and the outcoming results

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39

Linn, Linsey Margaret. "Heat transfer in mixing vessels using induction heated impellers." Thesis, University of Bradford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253836.

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40

Omeich, Maher. "Étude et expérimentation d'un dispositif de transfert inductif séquentiel." Paris 6, 1989. http://www.theses.fr/1989PA066379.

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Le transfert inductif d'énergie a été l'objet d'une étude approfondie au laboratoire d'électrochimique d'Orsay. Cette étude a abouti a l'élaboration d'un dispositif destine a valider le principe du transfert inductif d'énergie non dissipatif. Dans la première partie de ce travail nous avons étudie le transfert inductif: son principe de fonctionnement, les quantités électriques mises en jeu tels que les courants et les tensions, les grandeurs physiques essentielles engagées tel que le flux, l'état énergétique du système et l'optimisation du fonctionnement. Cependant, la deuxième partie présente une étude constructive d'un dispositif destine a la validation du principe et la modélisation de ce dernier faite par le biais d'un micro-ordinateur. La dernière partie de ce rapport a pour objet l'étude expérimentale du système. Nous avons décrit la maquette choisie pour valider le transfert inductif non dissipatif ainsi que son système de commande. Les résultats obtenus et une discussion des problèmes rencontres sont aussi un sujet de cette partie. L'étude et l'expérimentation du système nous ont conduit a la validation du principe de transfert inductif d'énergie non dissipatif

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Low, Zhen Ning. "High efficiency loosely coupled wireless power transfer system via magnetic induction." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024707.

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Yring, Malin. "Textile Integrated Induction : Investigation of Textile Inductors for Wireless Power Transfer." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-10264.

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This research has its basis in developments within the field of inductive powering and wireless power transfer, WPT, and more specifically one the branch within this field, which is called magnetic resonance coupling. This principle enables efficient power transfer from a transmitting unit to a receiving unit at a distance of some times the unit diameter. The developments within magnetic resonant coupling are together with the possibilities and challenges of today’s smart textile industry the starting point to investigate a novel textile-based product concept for WPT by combining both technologies. Multiple textile samples, consisting of cotton and electrically conductive copper yarns, were produced by weaving technique, additional assembling of electronic components were performed manually and several measurements were carried out to investigate the sample characteristics and the sample performance in terms of power transfer. The produced samples showed to behave similarly to conventional inductors and were able to transfer power over some distance.

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Chevasson, Vincent. "Dyades à base d’oligoprolines pour un transfert d’énergie directionnel." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAF055.

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Au cours de cette thèse, des dyades chromophoriques à base d’oligoprolines ont été développées afin d’étudier les transferts d’énergies au sein de système hélicoïdaux. L’étude préliminaire de ces dyades n’a pas permis d’obtenir l’étude de transfert d’énergie souhaitée. La présence conjointe de deux conformères, ainsi que des problèmes de pureté, semblent en être la cause. C’est pourquoi dans un second temps, plusieurs modèles d’oligoprolines ayant une conformation largement majoritaire ont été conçus. Basés sur un blocage de conformation via des effets stériques cumulés, les modèles présentés conservent une unique conformation dans des solvants favorisant les deux types d’hélice. Pour finir, une propagation de la conformation a été étudiée à partir des composés modèles afin de créer une dyade chromophorique induite. L’étude photo-physique de celle-ci permet d’en étudier le transfert d’énergie
During this thesis, chromophoric dyads based on oligoprolines have been developed in order to studyEnergy transfer within helical systems. Preliminary studies of these dyads were unsuccessful to study thedesired energy transfer. The presence of two conformers and purity problems seems to be responsible. This iswhy, in a second step, several oligoproline models with a major conformation were designed. Based on aconformation induction via cumulative steric effects, the models presented maintain a unique conformation insolvents favoring both types of helices. Finally, a propagation of the conformation will be studied based on themodel compounds in order to create an induced chromophoric dyad. The photo-physical study show anefficient energy transfer

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Patel, Bhakti. "The induction of mating ability for genetic analysis in industrial yeasts." Thesis, London South Bank University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245133.

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Davis, Aaron Patrick. "Apoptotic and Epigenetic Induction of Embryo Failure Following Somatic Cell Nuclear Transfer." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1941.

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Somatic cell nuclear transfer (SCNT) is a useful tool for selective breeding, conservation, and production of transgenic animals. Despite the successful cloning of several species, high rates of embryo failure following SCNT prevent the wide-scale use of the technique. Embryos produced through cloning have a higher incidence of developmental arrest, decreased developmental potential, frequent implantation failures, and increased incidence of abortion. The objective of this dissertation research was to characterize the factors that lead to SCNT failures by examining epigenetic and apoptotic pathways that can negatively influence the development of cloned preimplantation embryos. Aberrant genome reprogramming is generally considered to be a key factor in the failure of SCNT embryo development. Therefore, we used bisulfite pyrosequencing technology to compare DNA methylation patterns of several genes critical for embryonic development (POU5F1, NANOG, SOX2, and KLF4) in SCNT and in vitro fertilized (IVF) blastocyst stage embryos. The methylation profiles obtained from these experiments indicate that methylation patterns of the POU5F1 gene were undermethylated compared to IVF embryos, suggesting reprogramming did occur, but that the reduced methylation was inappropriate for the blastocyst stage. Furthermore, aberrant methylation profiles were detected for SOX2 and NANOG, suggesting that problems of genome reprogramming following SCNT can be gene-specific or localized. Because high rates of apoptosis are associated with failure of preimplantation embryos, we compared the activation of the P53-mediated apoptosis pathway in individual IVF and SCNT preimplantation embryos at multiple developmental stages. This pathway is activated in response to cell stress and genomic instability, and in response to the expression of genes associated with somatic cell reprogramming. Evidence from gene expression and immunohistochemistry analyses suggests that the P53 pathway is frequently active in SCNT embryos. Also, we detected expression of several factors known to induce apoptosis more frequently and at higher levels in SCNT embryos. Collectively, the work presented here illuminates some of the molecular consequences of incomplete or inappropriate genome reprogramming in cloned embryos. The identification of these factors may lead to interventions that target the apoptosis pathway during preimplantation development and increase SCNT success rates.

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Buchanan, Carrie C. "Micronuclei induction in AG01522 cells is independent of temperature and linear energy transfer." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44848.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2008.
Includes bibliographical references (p. 42-44).
The bystander effect describes radiation-induced biological effects in nonirradiated cells that have received signals from irradiated cells. In a co-culture experiment, the bystander signaling is proposed to occur via the medium. Using a co-culture setup, the work in this thesis investigates the effects of temperature as an experimental parameter and linear energy transfer (LET) dependence on the bystander effect. Using the micronucleus assay and primary human AG01522 fibroblast cells co-cultured as both the target and bystander cells, the incidence of micronuclei in both X-ray irradiated and alpha particle irradiated bystander experiments were ~2 fold over control averages. In the temperature experiment, there were no significant differences between bystander cells co-cultured with cold (4°C) target cells and those co-cultured with warm control target cells. These results have shown, for AG01522 fibroblasts, that the bystander effect is independent of temperature and LET.
by Carrie C. Buchanan.
S.B.

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Kamotesov, Sergkei. "Transmission d’énergie par induction électromagnétique en plastronique 3D." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1353.

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L’objectif de la thèse est d’évaluer l’intérêt de la plastronique 3D dans le domaine de la transmission d’énergie à distance par induction électromagnétique (TEDIM). En effet, la TEDIM est actuellement basée sur des inductances planes, qui n’autorisent un transfert d’énergie entre émetteur et récepteur que sur une courte à moyenne distance, à condition de plus qu’elles soient alignées. Dans ce manuscrit est étudié le cas particulier de récepteurs de forme 3D disposés à l’intérieur d’une boite émettrice de 50 cm de côté comportant 4 inductances émettrices. Différents récepteurs avec des inductances plastroniques ont été étudiés en abordant les questions suivantes : résonance des inductances plastroniques à 6,78 MHz, dimensionnement et forme en 3D. Ainsi, un récepteur en plastronique de forme quasi-sphérique (Ø 8 cm) a été fabriqué par impression 3D, structuration laser directe, métallisation autocatalytique et électrodéposition. Celui-ci a été doté de 3 inductances réceptrices solénoïdes en plastronique et disposées orthogonalement sur les équateurs ayant chacune un facteur de qualité supérieur à 129 ±10. Les résultats expérimentaux sont les suivants : (1) le récepteur reçoit jusqu'à 4,33 W avec un rendement de 15,8 % au centre de la boite, et (2) lorsque l’on fait varier la position et l’orientation du récepteur dans la boite, la disposition des inductances permet, dans une large mesure, de moyenner la puissance reçue. En conclusion, la plastronique permet d’intégrer, relativement aisément, des inductances autorisant une TEDIM, dans les habillages d’appareils électroniques, à la manière des antennes électromagnétiques intégrées par plastronique dans les téléphones intelligents. Ces inductances peuvent épouser la forme 3D de ces habillages, ce qui permet de concevoir des récepteurs et émetteurs omnidirectionnels
The objective of this thesis is to evaluate the interest of 3D molded interconnect devices technologies 3D-MID for wireless power transfer (WPT) through electromagnetic induction. WPT systems mostly uses planar coils that allows transfer between receiver and emitter at low and mid-range distance, at the condition that they are well aligned. We studied a specific case with a 3D receiver enclosed in a half meter box with 4 emitting inductors on 4 sides. Three questions were examined: the magnetic resonance of 3D-MID inductors at 6.78 MHz, their dimensions and their 3D shape. The nearly spherical shape 3D-MID receiver (Ø 8 cm) was 3D printed, activated with laser direct structuring (LDS), autocatalytic metallization and electroplating. It has 3 solenoid receiving inductors, each with quality factor above 129 ±10, placed orthogonally on the equators. The experimental results show: (1) the receiver is able to receive 4.33 W at 15.8 % efficiency in the middle of the box and (2) that we can change position and orientation of the receiver in the box, the placement of the inductors allows, in a widely meaning, to mean the received power. In conclusion 3D-MID allows to integrate, relatively easily, inductors for WPT, in the casing of electronics devices, in the same way as for 3D-MID electromagnetic antennas in smartphones. These inductors can 3D-shape the casing, which will allow the design of omnidirectional receivers

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48

Delmas, Alain. "Le transfert inductif d'énergie : caractéristiques générales et élaboration de l'élément de commutation." Paris 6, 1988. http://www.theses.fr/1988PA066187.

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Degenbeck, Helmut. "Transfer of chirality in new supramolecular complexes as design principle for future asymmetric catalysts." Doctoral thesis, Universitat Rovira i Virgili, 2011. http://hdl.handle.net/10803/37353.

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En el curso de esta Tesis Doctoral, se sintetizaron librerías de (1,2)-diaminas enantiopuras y 2,2’-bifenoles pro-quirales. La transferencia de quiralidad desde la diamina al bifenol, mediante puentes de hidrógeno o coordinación a un metal (ZnII, CuII), fue demostrada por dicroísmo circular (DC). El comportamiento en disolución de los complejos supramoleculares (usando puentes de hidrógeno), así como sus constantes de asociación, fue estudiado mediante valoraciones de RMN, UV-vis y ITC. La determinación de las configuraciones absolutas de los complejos de ZnII se consiguió mediante la resolución de las estructuras de rayos-X y los estudios de DC, tanto a un nivel teórico como experimental. Un nuevo ligando fosforado, potencialmente catalítico, fue preparado a partir de 2,2’-bifenol, mostrando el camino para el desarrollo de nuevos catalizadores supramoleculares.
During the course of the thesis libraries of chiral (1,2)-diamines and prochiral 2,2’-biphenol derivatives were synthesised. The transfer of chirality from the diamine to the biphenol moiety mediated either by hydrogen bonding or coordination to a metal centre (ZnII, CuII) was demonstrated by CD (circular dicroism). The behaviour in solution of the hydrogen bonded complexes was investigated by NMR spectroscopy, UV-vis and ITC titrations (determination of association constants. The determination of absolute configurations of the ZnII complexes was achieved by X-ray structure determination and CD analyses both on the experimental and theoretical level. Last but not least, a new potentially catalytic phosphane ligand was derived from a dynamically racemic 2,2’-biphenol derivative.

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50

Le, Guen Valentin. "Induction de la tolérance allogénique par transfert de gène dans le foie." Nantes, 2016. https://archive.bu.univ-nantes.fr/pollux/show/show?id=b85ec169-3bd5-4aa3-867c-0d702ddbe083.

Full text

Abstract:

L'induction de la tolérance immune spécifique du donneur est une bonne alternative à la prise d'immuno-suppresseurs au long terme, classiquement utilisés pour limiter le rejet de greffe. Les molécules de Complexe Majeur d'Histocompatibilité du Donneur (CMH) sont les principales cibles de la réponse allogénique chez le receveur en transplantation. Le transfert de gène ciblant le foie à l'aide de vecteurs viraux induit la tolérance au produit du transgène. Pour déterminer si l'expression d'un alloantigène par les hépatocytes induit la tolérance et favorise l'acceptation de la greffe, des souris C57Bl/6 (H-2b) ont été traitées à l'aide d'un vecteur AAV (pour Adeno Associated Virus) permettant l'expression du CMH I H-2Kd par les hépatocytes. Les souris sont tolérantes à l'alloantigène et l'expriment à leur membrane à long terme, même après vaccination à l'aide d'un adénovirus. Après induction d'un diabète, des souris traitées avec l'AAV rejettent plus tardivement des greffes d'îlots pancréatiques de souris Balb/c (H-2d), et 40% d'entre elles sont tolérantes (survie >100 jours). L'expression de H-2Kd dans le foie induit l'expansion localement de LT CD8+ allospécifiques et suppresseurs. Leur transfert adoptif chez des souris naïves diabétiques améliore la survie de greffe allogéniques d'îlots pancréatiques. Nous avons démontré pour la première fois que l'expression à long terme d'une molécule de CMH I induit la génération d'un sous-type de LTreg CD8+ allospécifiques favorisant la tolérance à des allogreffes. Le transfert de gène dans le foie est une stratégie prometteuse pour l'induction de la tolérance spécifique du donneur in vivo
Induction of donor-specific immune tolerance is a good alternative to chronic life-long immunosuppression for the avoidance of allograft rejection. Donor major histocompatibility complex (MHC) molecules represent the main targets of the allogeneic immune response of transplant recipients. Liver-targeted gene transfer with viral vectors induces tolerance toward the encoded antigen. To determine whether alloantigen gene transfer to hepatocytes induces tolerance and promotes graft acceptance, C57Bl/6 (H-2b) mice were treated with adeno-associated viral (AAV) vector targeting the expression of the MHC I molecule H-2Kd to hepatocytes. AAV H-2Kd treated mice were tolerant to the alloantigen, as demonstrated by its long-term expression at the membrane of the hepatocytes, even after a highly immunogenic challenge with an adenoviral vector. In addition, after induction of diabetes, the AAV treated mice had significantly delayed rejection of fully allogeneic pancreatic islet grafts from Balb/c mice (H-2d), with more than 40% recipients tolerant (>100 days). AAV mediated expression of H-2Kd in the liver induced the local expansion of CD8+ T lymphocytes with allo-specific suppressive properties. The adoptive transfer of these liver-generated CD8+ Tregs into naive diabetic mice promoted the long-term survival of allogeneic pancreatic islet grafts. We demonstrate for the first time that AAV-mediated long-term expression of a single MHC I molecule in the liver induces the generation of a subset of allospecific CD8+ Treg cells, which promotes tolerance toward fully allogeneic graft. Liver gene transfer represents a promising strategy for in vivo induction of donor-specific tolerance

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