Dissertations / Theses: 'Inductive coupling'

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Voranantakul, Suwan 1962. "CONDUCTIVE AND INDUCTIVE CROSSTALK COUPLING IN VLSI PACKAGES." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/277037.

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Svensson, Andreas. "Design of Inductive Coupling for Powering andCommunication of Implantable Medical Devices." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105112.

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Technological advances over the years have made it possible to reduce the size and power consumption of electronics. This has led to significant advances for biomedical sensors. It is now possible to reduce the size enough to create implantable sensors. This type of sensors can for instance be used to measure the glucose level of diabetes patients. An implantable sensor can significantly simplify the measurement procedure. Taking a measurement can be as simple as turning on a device, capable of receiving the data sent by the sensor. Unfortunately, the lifetime of this type of sensors can be limited by the battery of the implanted sensor. To improve the lifetime, the battery has to be replaced. Instead of a battery, energy harvesting can be used. One promising such method is to transfer power from outside the body to the implanted sensor. This thesis focuses on one such way, inductive coupling. Inductive coupling, can be used both to transfer power from an external device to the sensor, and to transfer data from the sensor to the external device. In this thesis a system for wireless power transfer has been proposed. The system is based on state of the art circuits for inductive powering and communication, for implantable devices. The system is adapted for powering an implantable biomedical sensor including a PIC16LF1823 microcontroller. The system includes asynchronous serial communication, from the microcontroller in the implantable device to the external reader device using load shift keying. The external device of the system, has been implemented in two different versions, one using a printed circuit board (PCB), and one simplified version using a breadboard. The implantable device has been implemented in three different versions, one on a PCB, one simplified version using a breadboard and finally one application specific integrated circuit (ASIC). All three implementations of the implantable devices use a resistor to simulate the power consumption of an actual biomedical sensor. The ASIC implementation contains only the parts needed for receiving power and transmitting data. The ASIC was designed using a 150nm CMOS process. The PCB implementations of both devices have been used to measure the system performance. The maximum total power consumption was found to be 107 mW, using a 5 V supply voltage. The maximum distance for powering the implantable device was found to be 4.5 cm in air. The sensor, including the microcontroller, is provided with 648 μW of power at the maximum distance. A raw data rate of 19200 bit/s has been used successfully to transfer data. Additionally, oscilloscope measurements indicates that a data rate close to 62500 bit/s could be possible. Simulations of the proposed ASIC show that the minimum total voltage drop from the received AC voltage to the regulated output voltage is 430 mV. This is much smaller than for the PCB implementation. The reduced voltage drop will reduce the power dissipation of the implantable device and increase the maximum possible distance between the external device and the implanted devices. The ASIC can provide 648 μW of power at a coupling coefficient k=0.0032. Tekniska framsteg genom åren har gjort det möjligt att minska storleken och effektforbrukningen hos elektronik. Detta har lett till stora framsteg för biomedicinska sensorer. Det är nu möjligt att tillverka elektronik liten nog att användas i sensor implantat. En sådan sensor skulle till exempel kunna användas for att mäta glukos värden i blodet hos diabetes patienter. Ett sådant Implantat kan forenkla mätningar, genom att endast en mottagare behövs for att kunna få mätvarden från sensorn. Livslängden för denna typ av sensor kan forbättras genom att undvika att använda ett batteri som energikalla. Istället kan energin överföras från en apparat utanför kroppen till implantatet. Denna rapport handlar om ett sadant sätt, namligen induktiv energiöverföring. Denna teknik kan användas både till att överfora energi till implantatet, och till att överfora data från implantatet till den externa enheten. I den har rapporten beskrivs ett system for tradlös energiöverforing. Systemet ar baserat på den senaste tekniken for induktiv överforing, och har anpassats for att förse en sensor som inkluderar en PIC16LF1823 mikrokontroller. Systemet inkluderar också asynkron seriell kommunikation från mikrokontrollern i implantatet till den externa enheten genom att använda lastmodulering. Den externa enheten har implementerats i två versioner. En full version på ett kretskort, samt en förenklad version pa ett kopplingsdäck. Tre versioner av kretsarna for implantatet har använts, en förenklad version på ett kopplingsdäck, en version på kretskort och en applikations specifik integrerad krets. Den applikations specifika integrerade kretsen har simulerats med modeller från en 150 nm CMOS tillverkningsprocess, medans de andra versionerna har konstruerats av diskreta komponenter och använts för mätningar. Mätresultat från kretskortsimplementationen visar på en maximal räckvidd pa cirka 4,5 cm i luft, med en total effektforbrukning pa 107 mW. Vid det maximala rakvidden mottags 648 μW. En dataöverföringshastighet pa 19200 bitar/s har uppnåtts med kretskorts versionen. Mätningar med oscilloskop visar att det kan vara möjligt att öka överforingshastigheten till 62500 bitar/s. Simuleringsresultat for den integrerade kretsen visar att det lägsta spänningsfallet från den mottagna växelspanningen till den reglerade likspänningen är 430 mV. Detta ar betydligt mindre for den integrerade kretsen än för kretskorts versionen, vilket resulterar i en lagre effektforbrukning och troligen en längre räckvidd för systemet. Den integrerade kretsen kan leverera 648 μW vid en kopplingsfaktor pa k=0.0032.

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Prasad, Rao Pasupuleti Krishna. "Investigation and Study of Crosstalk." Thesis, Linköpings universitet, Fysik och elektroteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-114536.

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Crosstalk is defined as an unwanted coupling between the conductors. By this it is meant that signals from one of the signal conductors (a generator in this case) are coupled to another signal conductor (receptor), or conductors (receptors), depending on the number of conductors in the vicinity of the generator. Crosstalk in this way affects the signal level on the receptor and thereby affects the total system performance within the system. This can happen in several ways, one of which is through edge coupling. Edge coupling is a process where two signal conductors are placed beside each other in the same layer while the ground conductor could have been placed either under these conductors, in a separate layer like Mclin (Microstrip coupled lines) and Sclin (Coupled striplines), or beside the signal conductors as in Cpwcpl2 (Coplanar wave guide coupled lines). This then means that edge coupling occurs through the sides where the generator and the receptor are facing each other. Broadside coupling is another way, where it occurs when the signal conductors are broadside faced to each other in different layers with reference planes above and below these signal conductors. Coupling of the signals from the generator to the receptor can occur through capacitive coupling or inductive coupling. Capacitive coupling, also known as electrical coupling, occurs due to the difference in the characteristic impedance of the generator (usually 50 or 100 §Ù) and its heavy load (1 k§Ù or more) which results in high voltage difference between the generator and the reference conductor (ground). This leads to the creation of a charge across the generator and the receptor-facing sides and finally results in the electric field coupling between them. On the other hand, inductive coupling, also known as magnetic coupling, occurs when the load is less than the characteristic impedance of the generator, and this thereby results in a heavy current flow through the generator which in return results in a strong magnetic field around itself and so leads to magnetic coupling to the receptor. The aim in this thesis is to measure both the capacitive and inductive coupling load¡¯s impacts on both the edge coupling and the broadside coupling models through crosstalk on the receptor. This thesis starts with the background and corresponding theory and equations to the crosstalk coupling. Later on it tests both the edge- and broadside coupling models with different physical properties exploitation. Inductive and capacitive loads are used to measure the resulting crosstalk coupling. Particularly to see the effect of capacitive and inductive coupling in reality in multi layered PCB, a Sbclin (Broadside coupled striplines) model has been used with different angular placement of the generator. Finally mclin physical models are compared with the simulated models and corresponding differences are discussed. It can be concluded that crosstalk effect increases or decreases with physical properties exploitation. Crosstalk also increases with the wrong termination of the load.

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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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Murtaza, Ghulam <1988&gt. "Wireless Power Link Design for Both High-Power Inductive Coupling and Smart Metasurfaces Exploitation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10260/1/ThesisGM.pdf.

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As future technologies are going to be autonomous under the umbrella of the Internet of things (IoT) we can expect WPT to be the solution for intelligent devices. WPT has many industrial and medical applications both in the near-field and far-field domains. Considering the impact of WPT, this thesis is an attempt to design and realize both near-field and far-field WPT solutions for different application scenarios. A 27 MHz high frequency inductive wireless power link has been designed together with the Class-E switching inverter to compensate for the efficiency loss because of the varying weak coupling between transmitter and receiver because of their mutual misalignment. Then a system of three coils was introduced for SWIPT. The outer coil for WPT and the inner two coils were designed to fulfil the purpose of communication and testing, operating at frequencies different from the WPT coil. In addition to that, a trapping filter technique has also been adopted to ensure the EM isolation of the coils. Moreover, a split ring resonator-based dual polarization converter has been designed with good efficiency over a wide frequency range. The gap or cuts have been introduced in the adjacent sides of the square ring to make it a dual-polarization converter. The converter is also stable over a wide range of incident angles. Furthermore, a meta-element based intelligent surface has been designed to work in the reflection mode at 5 GHz. In this research activity, interdigital capacitors (IDCs) instead of ICs are introduced and a thin layer of the HfZrO between substrate and meta elements is placed whose response can be tuned and controlled with the applied voltage to achieve IRS.

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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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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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Albesa, Querol Joan. "Monitoring switch-type sensors and powering autonomous sensors via inductive coupling: application to removable seats in vehicles." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/101400.

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This thesis explores the feasibility of using inductive links for a vehicle application where wiring an electronic control unit (ECU) to the sensors or detectors become unfeasible or unpractical. The selected application is occupancy and belt detection in removable vehicle seats. Two ways of using inductive links are considered: 1) passive detection of the state of the seat detectors from a readout unit and 2) remote power transmission to a detection unit and subsequent data transmission by a wireless transceiver. Inductive links have been widely proposed for sensors placed in harsh or inaccessible environments, where wiring is unpractical. Usually, the sensor forms part of an LC resonant network. The resonant frequency is dependent on the quantity to be measured and is estimated from a coupled reader. We propose the use of inductive links for switch-type sensors. First, a comprehensive analysis for an arbitrary number of sensors is presented. Secondly, we show the feasibility of using inductive links for occupancy and belt detection in removable vehicle seats. The state (open or closed) of the related sensors was attained by first measuring the equivalent resistance of the readout inductor and then estimating its resonant frequency. Commercial ferrite-core coils were used to increase the detection distance. Experimental tests were carried out using an impedance analyzer connected to the readout coil and commercial seat detectors connected to the resonant network. The detection of the sensors¿ state was feasible at all tested distances, from 0.5 cm up to 3 cm. The second proposed alternative consists on remote powering, via an inductive link, the electronic device where the seat detectors are connected. Resonant coupled coils were used in order to increase the powering distance range and the power efficiency. Working frequency was restricted to 150 kHz. Commercial small-size magnetic-core coils were selected and their resistance and quality factor over frequency measured. At the receiving network, a rectifier and a voltage regulator were required to provide a DC voltage supply to the autonomous sensor. Four type of voltage regulators were compared from the point of view of the system power efficiency. Both a theoretical analysis and experimental results are presented. Results showed that shunt regulators provide the best power efficiency over the other alternatives, which are linear series and switching buck and boost regulators. On the other hand boost regulators led to an unstable behavior of the system in most of the cases. The use of rechargeable batteries was also considered in order to increase the power efficiency. Achieved power efficiencies were around 40%, 25% and 10% for coil distances of 1 cm, 1.5 cm and 2 cm respectively. Experimental tests also showed that the autonomous sensor was properly powered up to coil distances of 2.5 cm. Finally, different types of coils were assessed and the effect of metallic structures analyzed for the intended application. The final aim is, on the one hand, to increase the powering distance and, on the other hand, to minimize the influence of the metallic structures. Three different coil types, two with ferrite-core coils and one with an air-core coil were used. Numerical results showed that ferrite-core coils are less affected by the presence of metallic structures. Experimental results showed that the air-core coils provided a larger powering distance thanks to its much larger winding diameter. However, when approaching a metallic plate, the transferred power with the air-core coils to the load was insufficient for the intended application. On the other hand, ferrite-core coils barely noticed the presence of the metallic plate. As for the passive detection, the presence of a metallic plate below the primary air-core coil slightly affected the measured resistance values but detection for the four possible states of the seat detectors was still possible. Algunes aplicacions a l'entorn de l'automòbil no són possibles si no és mitjançant la connexió sense fils dels seus dispositius a causa que el cablejat és difícil o inviable. Alguns exemples els trobem en el monitoratge de sensors situats en parts rotatòries, com les rodes, o en elements extraïbles, com els seients. Els sistemes de monitoratge de la pressió de l'aire en les rodes (TPMS) són d'obligat compliment als EUA i ho seran en breu també als països membres de la UE per als vehicles de categories M1 o N1 aprovats a partir de l'1 de novembre de 2012 o per als vehicles matriculats a partir de l'1 de novembre de 2014. Actualment, els sistemes TPMS existents al mercat estan alimentats per piles. Amb tot, la vida útil exigida per a les bateries és d'uns 10 anys, esdevenint el seu ús un autèntic repte. Un altre element en contra de l'ús de bateries és la directiva 2006/66/CE que limita el nombre màxim permès en els vehicles. D'altra banda, moltes furgonetes o mini furgonetes i vehicles familiars incorporen seients extraïbles amb l'objectiu d'aprofitar al màxim l'espai interior. Alguns models comercials incorporen en el seient extraïble el detector de cinturó de seguretat. Per evitar el cablejat, existeixen sistemes de detecció passiva mitjançant acoblament inductiu. A partir del present any 2012, una regulació de la agència nord-americana NHTSA requereix de l'ús de coixins de seguretat intel·ligents per minimitzar els riscos en nens. Aquests seients intel·ligents haurien de detectar si el passatger és un adult, una cadira infantil o si està lliure per evitar problemes ocorreguts en anterioritat amb els sistemes coixí de seguretat. Els sensors usats per a aquests coixins de seguretat intel·ligents requeririen d'energia per operar. Una opció per als seients extraïbles és la transmissió de potència via acoblament inductiu des del terra del xassís del vehicle fins al seient. També és possible usar l'acoblament inductiu per detectar l'estat de diversos sensors existents en els seients extraïbles mitjançant detecció passiva. Precisament, la detecció d'ocupació i de cinturó de seguretat en seients extraïbles ha estat seleccionada per aplicar la investigació present que consisteix, d'una banda, en el monitoratge de sensors de tipus commutat (dos possibles estats) via acoblament inductiu i, per una altra, en la transmissió mitjançant el mateix principi físic de la potència necessària per alimentar els sensors autònoms remots. En els dos casos, una primera bobina es fixaria en el seient extraïble, connectada als sensors, i una segona bobina se situaria sota la primera, en el terra del vehicle.

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Hanusaik, Linda Irene. "An evaluation of user performance with inductive coupling of hearing aids and telephone receivers incorporating receiver amplification." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29863.

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Previous research has shown the benefit obtained by hard of hearing people when using inductive means (T-switch) to couple their hearing aids to telephone receivers. Benefit provided by receiver amplification in the telephone handset has also been shown. Informal surveys of hard of hearing people indicate that many of them use telephones having a dual capability: magnetic coupling and receiver amplification. The objective of this investigation was to study user performance with this dual capability. In particular, the effect of receiver amplification on the speech perception ability (as measured by R-SPIN test items) of 10 hard of hearing subjects using inductive means to couple their hearing aid to a telephone receiver was examined under both good and poor telephone line conditions. The influence of the predictability of the speech material presented was also investigated by noting any difference between the subjects' performance on high predictability items and performance on low predictability items (of the R-SPIN test). Results showed that the use of receiver amplification in conjunction with inductive coupling significantly improved the subjects' speech perception scores. Not surprisingly, good telephone line conditions also significantly improved the subjects' scores. Improvement due to receiver amplification was noted, irrespective of line conditions. Similarly, improvement due to good line conditions was observed, irrespective of whether amplification was used or not. Both receiver amplification and good line conditions had significant and positive effects on both low predictability and high predictability scores. We conclude that with speech either in or out of context, receiver amplification will be of benefit to those who use inductive coupling. Clinical implications and recommendations are discussed. Medicine, Faculty of Audiology and Speech Sciences, School of Graduate

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Canales, Sebastian Nerea. "Full-wave analysis and design of a realistic rail-track circuit based on loosely-coupled inductive loops." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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This Master Thesis approaches the analysis and design of a novel solution for the “Circuito di binario (CdB”) i.e., a railway track circuit, that is used as a detection system of the trains for track management and is integrated into the signalling and safety systems on board. The presented CdB exploits an inductive loop system coupled to an S-shaped joint (replacing the previously used mechanical joints) in the audio-frequency range (from 8 to 16 kHz). The tracks, therefore, constitute a transmission route similar to a transmission line equipped with a Transmitter (Tx) and a Receiver (Rx), and can be used to transmit information. As a starting point, different electromagnetic simulations of a prototype system of the CdB (scale 1:4), realized in the ARCES laboratories of the University of Bologna, have been carried out. A 3D replica of the CdB has been realized in CST and electromagnetically analysed. Afterward, the Rail Trak with its actual dimension (scale 1:1) has been simulated and the length of the S joint has been optimized in such a way that that the loops that are not in the Tx-Rx circuit are highly decoupled, whereas the coupling of those that are part of the communication circuit is maximum. Subsequently, with the purpose to lighten the whole CdB electromagnetic simulations, the rail-track has been analysed alone in order to extract an equivalent circuit to be used in AWR together with the outputs (scattering matrices) of the electromagnetic simulations of the S joint with loop (both Tx and Rx). The agile obtained optimization tool has allowed the design of the two matching networks with lumped components (one between the transmitting circuit and the Tx loop, the other between the Rx loop and the receiving circuit) for the maximization of the received power: the highest challenge of this project has been the satisfaction of the matching over such a broad frequency band (equal to one octave).

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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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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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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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Canturk, Mehmet. "Modeling Of Helically Applied Current To The Inductively Coupled Radio Frequency Plasma Torch In Two Dimensions." Phd thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12604691/index.pdf.

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The electrodeless plasma discharge is typically driven by radio frequency (RF) power supply within the range (0.2 &iexcl 40 MHz). The applied power is coupled into the plasma inductively called inductively coupled plasma (ICP). RF ICP technique has achieved significance importance in a diversity of research and industrial applications for over the last threes decades. It is still required to undertake both theoretical and experimental research. In this work, RF ICP technique is applied on the torch modeling in 2D. Based on extended electromagnetic vector potential representation, an axisymmetric model in 2D is proposed for the calculations of the electromagnetic fields in an RF ICP torch. The influence of axial vector potential is included to the vector potential formulations. This is achieved by imposing a helical current carrying wire configuration. The corresponding governing equations are solved numerically by applying finite element method (FEM) using commercial partial differential equation solver (Flex PDE3). Based on this model, the plasma behavior and properties are examined in terms of plasma parameters. Besides, a comparative iii analysis is made between proposed model called helical configuration and the one currently available in the literature called circular configuration. This study shows relatively little difference between temperature fields predicted by two models. However, significant difference is observed between corresponding flows and electromagnetic fields. Especially, tangential flow which is observed in helical configuration vanishes in circular configuration. The proposed model offers an effective means of accounting for the variations of the helical coil geometry on the flow and temperature fields and achieving a better representation of the electromagnetic fields in the discharge. Finally, it is concluded that minimum number of turns (n = 2) yields significant difference between two models whereas, maximum allowable number of turns yield no distinctions on the results of two models in terms of azimuthally applied current. However, axial effect of current still exists but very small with respect to the result obtained with minimum number of turns.

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Nguyen, Thanh Trung. "Méthode PEEC inductive par élément de facette pour la modélisation des régions conductrices volumiques et minces." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT049/document.

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La méthode PEEC est connue comme une bonne méthode pour la modélisation des interconnexions électriques dans les domaines de l’électronique de puissance et l’électrotechnique. Elle s'applique à une large gamme de dispositifs : circuits imprimés, bus-barres, conducteurs massifs. Elle est particulièrement bien adaptée pour la modélisation de régions conductrices du type filaire. Cependant, elle est requise d’un maillage structuré(discrétisation des géométries en quadrangles) et l’approche est limitée en fréquence (grande épaisseur de peau). Enfin, il semble actuellement difficile d’envisager la modélisation de conducteurs volumiques dans une formulation PEEC standard.Cette thèse développe des formulations intégrales en utilisant des éléments de facette afin d’lever des verrous de la méthode PEEC standard évoqués ci-dessus. Elle constitue de fait une généralisation de la méthode PEEC standard par la prise en compte de maillages non structurés (volumique et surfacique) et la prise en compte de notion de régions minces à faible épaisseur de peau.Les applications visées sont la modélisation de systèmes de conducteurs complexes (des régions non simplement connexes) en prenant en compte des connexions entre des régions (volumique/filaire, surfacique/filaire,volumique/surfacique et surfacique/surfacique) The PEEC method is known as a good method for modeling electrical connections in the domains of powerelectronics and electrical engineering. It applies to a wide range of devices: printed circuits, bus-bars, solidconductors. It is particularly well adapted for modeling the wire type conductive regions. However, it is requireda structured mesh (discretization geometries quadrangles) and this approach is limited in frequency (high skindepth). Finally, it now seems difficult to envisage modeling of the volume conductors in standard PEECformulation.This thesis develops integrals formulations using facet elements to improve the above mentioned limitations ofthe standard PEEC method. It is in fact a generalization of the standard PEEC method by taking into accountunstructured meshes (volume and surface) and taking into account the notion of thin region with a small skindepth.The applications are the modeling of complex systems of conductors (non-simply connected regions) taking intoaccount the connections between regions (volume / wireframe, surface / wired volume / surface and surface /surface)

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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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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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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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Arkeholt, Simon. "Induction in Printed Circuit Boards using Magnetic Near-Field Transmissions." Thesis, Linköpings universitet, Teoretisk Fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-148788.

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In 1865 Maxwell outlined the theoretical framework for electromagnetic field propagation. Since then many important developments have been made in the field, with an emphasis on systems using high frequencies for long-range interactions. It was not until recent years that applications based on short-range inductive coupling demonstrated the advantages of using low frequency transmissions with magnetic fields to transfer power and information. This thesis investigates magnetic transmissions in the near-field and the possibility of producing induced voltages in printed circuit boards. A near-field magnetic induction system is designed to generate a magnetic flux in the very low frequency region, and used experimentally to evaluate circuit board induction in several interesting environments. The resulting voltages are measured with digital signal processing techniques, using Welch’s method to estimate the spectrum of the received voltage signal. The results show that the amount of induced voltage is proportional to the inverse cube of the transmission distance, and that the system is able to achieve a maximum induced voltage of 65 \micro V at a distance of 2.5 m and under line-of-sight conditions. It is also concluded that conductive obstructions, electromagnetic shielding and background noise all have a large impact on the obtained voltage, either cancelling the signal or causing it to fluctuate.

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Nerone, Mariano. "Design and development of an embedded system for electric motor data acquisition." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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This thesis regards the design and implementation of an embedded system for electric motor data acquisition. In particular, it has been realised an embedded system capable to acquire temperatures inside the rotor of an electric motor. Two prototypes has been designed: one features an innovative NFC data over power technology, the other one uses an inductive coupling system for powering up a microcontroller alongside a BLE module onboard.

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Kureekkal, Tony Sabu. "Designing a Wireless Charger for Smartphones." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industridesign, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-46964.

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The wireless charging market has seen exponential growth in recent years and wireless charging is quickly becoming the standard in consumer electronic devices to eliminate inconveniences of wired chargers. The adoption of wireless charging technology is most visible in the smartphone industry. This thesis report elicits the process involved in designing a Wireless charger that complies with the Qi- Wireless Standards set by the Wireless Power Consortium. The drawbacks of current product offerings and user needs are identified, and conceptual solutions that could strengthen the wireless charging experience are explored. The most promising solution is developed upon which results in a full-scale functional prototype.

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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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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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Eid, Elie. "Caractérisation et modélisation électrique des phénomènes de couplage par les substrats de silicium dans les empilements 3D de circuits intègrés." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENT021.

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Afin d’améliorer les performances électriques dans les circuits intégrés en 3D, une large modélisation électromagnétique et une caractérisation haute fréquence sont requises. Cela a pour but de quantifier et prédire les phénomènes de couplage par le substrat qui peuvent survenir dans ces circuits intégrés. Ces couplages sont principalement dus aux nombreuses interconnexions verticales par unité de volume qui traversent le silicium et que l’on nomme « Through Silicon Vias » (TSV).L’objectif de cette thèse est de proposer des règles d’optimisation des performances, à savoir la minimisation des effets de couplage par les substrats en RF. Pour cela, différentes configurations de structures de test utilisées pour analyser le couplage sont caractérisées.Les caractérisations sont effectuées sur un très large spectre de fréquence. Les paramètres d’analyse sont les épaisseurs du substrat, les architectures des vias traversant (diamètres, densités, types de barrières), ainsi que la nature des matériaux utilisés. Des modèles électriques permettant de prédire les phénomènes de couplage sont extraits. Différents outils pour l’analyse de ces effets, sont développés dans notre laboratoire. Parallèlement un important travail de modélisation 3D est mené de façon à confronter mesure et simulation et valider nos résultats. Des stratégies d’optimisation pour réduire ces phénomènes dans les circuits 3D ont été proposées, ce qui a permis de fournir de riches informations aux designers In order to improve the electrical performance in 3D integrated circuits, a large electromagnetic modeling and a high frequency characterization are required. This has for goal to quantifiy and predicts the substrate coupling phenomena that can occur in these integrated circuits. These couplings are mainly due to the numerous vertical interconnections existing in a small volume and passing through the silicon, and so called “Through Silicon Vias” (TSV). The objective of this thesis is to propose rules for electrical performance optimization, in order to minimize the coupling effects in RF substrates. For this reason, different test structures configurations used to analyze the coupling are characterized.The characterizations are performed on a very wide frequency spectrum. The analysis parameters are the thicknesses of the substrate, the TSV architectures (diameters, densities, types of barriers), and the nature of the used materials. Electrical models for predicting the coupling phenomena are extracted. Different tools for the analysis of these effects are developed in our laboratory. At the same time, a considerable amount of 3D modeling is conducted to compare measurements with simulations and validate our results. Optimization strategies to reduce coupling phenomena in 3D circuits have been proposed; this has provided a wealth of information to designers

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Bhadra, Sharmistha. "Electrode-based wireless passive pH sensors with applications to bioprocess and food spoilage monitoring." IEEE, 2011. http://hdl.handle.net/1993/30366.

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This thesis purposes and develops inductively coupled LC (inductive-capacitive) pH sensors based on pH-sensitive electrode pair. The LC resonator circuit is based on a varactor and measures the low frequency potential difference. For wireless pH monitoring, the resonator circuit is integrated with a pH-sensitive electrode pair. This sensor demonstrates a linear response over 2 to 12 pH dynamic range, 0.1 pH accuracy and long-term stability. Accurate measurement of pH using electrode-based sensors is affected by temperature variation. A technique of simultaneously measuring two parameters, pH and temperature, with a single RLC resonator based sensor is presented. An algorithm is developed, which applies both pH and temperature measurement to incorporate temperature compensation in pH measurement. For in-fluid applications, an encapsulation method is applied to the LC resonator based sensor to reduce the influence of medium permittivity and conductivity on the sensor measurement. Non-invasive way to obtain reliable pH information from bacterial culture bioprocesses is demonstrated with the fluid embeddable sensor. The pH sensor is remodeled to an acidic and basic volatile sensor by embedding the electrodes in a hydrogel host electrolyte. Tests demonstrate that the volatile sensor has a detection limit of 1.5 ppm and 2 ppm for ammonia and acetic acid vapor, respectively. Application of the volatile sensor to fish spoilage monitoring shows that the sensor is capable of detecting the product rejection level with good sensitivity in real-time. It is important to develop low cost wireless passive pH sensor technologies for embedded applications such as bioprocess and food spoilage monitoring. The electrode-based passive LC sensor approach employed in this thesis overcomes drawbacks of some of the early developed passive pH sensors and can lead to an inexpensive implementation using printed electronics technology.

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Soares, Jaqueline dos Santos. "O acoplamento indutivo com bobinas On-Chip." Universidade Federal de Viçosa, 2007. http://locus.ufv.br/handle/123456789/4268.

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Made available in DSpace on 2015-03-26T13:35:22Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1377074 bytes, checksum: 9d0bcaa0daae6ad97072fe3a335f2cad (MD5) Previous issue date: 2007-02-26 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The quantum Hall effect (QHE) remains the target of an immense research effort twenty six years after its discovery. In fact this phenomenon has been a source of fundamental questions. Among the open problems in the field is the spatial distribution of the electric current in the quantum Hall effect. This question has been in debate since its discovery. Some experimental and theoretical results indicate the Hall current is distributed uniformly across the width of a Hall bar. Contradictorily, other results suggest the current flows mostly in a narrow region along the device s edges. Prominent works by Yahel et al. [PRL 76, 2149 (1996) and PRL 81, 5201 (1998)] shed new lights on the subject by using an experimental technique that came to known as inductive coupling . This method is based on the measurement of the nanovoltage signal induced by an alternating Hall current in a compact coil, carefully positioned above one edge of a Hall bar. It is perhaps the least invasive method available to study the current distribution in the QHE. It remained nonetheless a challenging experiment, as regards the positioning and making of the coil and the measurement of the minute induced voltage. We showed with calculations that it is possible to greatly simplify the aforementioned technique and make it more sensitive and useful by fabricating the coil on the chip containing the Hall bar. The concept was tested experimentally replacing the semiconductor Hall bar with a metal strip whose current distribution is known to be uniform from the electrodynamics. The voltage induced by the current in the metal strip in a nearby coil fits was measured. It fits in precisely, in magnitude and phase, with the values calculated. As our most important contribution, we found out that the presence of a two dimensional electron gas (2DEG), located 200 nm underneath the coil, increases the induced signal by thirty times. The magnitude and phase of the signal indicate it comes mostly from the current induced in the 2DEG by the alternating Hall current. This amplification effect renders a stronger signal with a sample containing a milimetric size Hall bar and a coil with ten turns, conveniently fabricated by simple optical lithography, than the signal measured by Yahel, using a ten times larger Hall bar and a handcrafted coil with 3,000 turns. We speculate that the effect of the 2DEG shall allow the use of our technique to map the current distribution in the QHE and also to study nanoscopic magnetic systems. O efeito Hall quântico (EHQ) permanece como foco de um imenso esforço de pesquisa vinte e seis anos após sua descoberta. De fato este fenômeno tem levantado uma série de questões fundamentais. Entre os problemas em aberto nesse campo está a distribuição espacial de corrente elétrica durante o efeito Hall quântico. Esta questão tem sido continuamente debatida desde a sua descoberta. Alguns experimentos e modelos teóricos indicam que a corrente se distribui uniformemente pela largura da ponte Hall. Contraditoriamente, outros resultados sugerem que a corrente flui predominantemente nas bordas do dispositivo. Trabalhos importantes de Yahel et al. [PRL 76, 2149 (1996) e PRL 81, 5201 (1998)] trouxeram novas pistas sobre o assunto usando a técnica experimental que ficou conhecida como "acoplamento indutivo . O método é baseado na medida da tensão induzida (da ordem de dezenas de nanovolts) por uma corrente Hall alternada em uma bobina compacta, cuidadosamente posicionada acima de uma das bordas da ponte Hall. Ele é talvez o método menos invasivo disponível para estudar a distribuição de corrente no EHQ. Entretanto, trata-se de uma técnica experimentalmente desafiadora no que se refere ao posicionamento e a fabricação da bobina e a medida tênue da tensão induzida. Mostramos com cálculos que é possível simplificar grandemente a técnica mencionada e fazê-la mais sensível e útil fabricando a bobina no mesmo chip da ponte Hall. O conceito foi testado experimentalmente substituindo a ponte Hall semicondutora por uma tira metálica cuja distribuição de corrente é conhecida a priori da eletrodinâmica. Medimos a tensão induzida pela corrente na tira metálica na bobina vizinha. O resultado ajusta-se perfeitamente, em magnitude e fase, aos valores calculados. Como nossa contribuição mais importante, descobrimos que a presença de uma gás bidimensional de elétrons (2DEG), localizado a 200 nm abaixo da bobina, aumenta o sinal induzido por um fator de trinta. A magnitude e a fase do sinal indicam que ele tem origem na corrente induzida no 2DEG pela corrente Hall alternada. O efeito de amplificação fornece um sinal mais forte em uma amostra contendo uma ponte Hall com dimensão milimétrica e com uma bobina com dez voltas, convenientemente fabricada por litografia óptica, do que o sinal medido por Yahel, usando uma ponte Hall dez vezes maior e uma bobina manufaturada com 3000 voltas. Especulamos que o efeito do 2DEG poderá permitir que a nossa técnica seja usada para mapear a distribuição de corrente no EHQ e também no estudo de sistemas magnéticos com dimensões nanométricas.

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Farnsworth, Bradley David. "Wireless Implantable EMG Sensing Microsystem." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1276263665.

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Laouamer, Rachid. "Chargeur de batteries à couplage inductif pour véhicule électrique." Grenoble INPG, 1998. http://www.theses.fr/1998INPG0062.

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Les travaux de cette thèse concernent les chargeurs à couplage inductif développés pour les flottes de véhicule électriques en libre service tel qu'envisagé dans l'opération PRAXITELE de EDF. L'objectif général était la définition de l'ensemble convertisseur-coupleur magnétique adapté à ce type de recharge. Les outils et les méthodes développés dans ce mémoire ont fait progresser la compréhension du couplage par induction, et éclairé le choix de la structure adaptée. L'étude méthodique des différentes structures à trois et à quatre éléments de stockage a fait ressortir quelques montages dignes d'intérêt. Les avantages et les inconvénients de chacun de ces montages ont été soulignés et une méthode de dimensionnement a été proposée. La structure choisie permet d'exploiter au mieux le transformateur à faible couplage que constitue le coupleur magnétique, d'alléger la partie embarquée et d'améliorer les caractéristiques de sortie du chargeur. Elle s'avère également être celle qui conduit au meilleur rendement énergétique de l'ensemble convertisseur-coupleur. Le schéma équivalent du coupleur, développé au laboratoire, nous a permis de simuler le comportement de l'ensemble convertisseur-coupleur, en prenant en compte tous les aspects utiles de son comportement. Cela a mené, en particulier, à l'évaluation des pertes de ce composant. Une vérification expérimentale soigneuse a confirmé cette évaluation avec une précision honorable The work presented in this thesis deals with inductive charging for electrical vehicle intended to self-service fleet as planned in EDF Praxitele project. The aim of this work was the definition of a converter-coupler set well adapted to this kind of charge. The methods developed in this report have improved the knowledge of inductive coupling, and clarified the selection of an adequate converter. After a survey of different topologies with three and four storage elements, we have brought out some interesting topologies. Both advantages and drawbacks of each topology have been emphasized and a design method has been proposed. The selected converter allows the use of parasitic coupler elements. It reduces the inboard weight and improves charger characteristics. Moreover it improves the global converter-oupler efficiency. The coupler equivalent circuit developed in our laboratory has been used to to simulate the whole converter-coupler set behavior, leading to losses evaluation. Careful measurements lead to the same value within a correct accuracy

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MORANDO, ANDREA. "EXPERIMENTAL AND MODELING ANALYSIS OF ELECTRIC SYSTEMS WITH HIGH CAPACITIVE AND INDUCTIVE COUPLINGS." Doctoral thesis, Politecnico di Torino, 2012. http://hdl.handle.net/11583/2496995.

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The present doctoral thesis Experimental and Modeling Analysis of Electric Systems with High Capacitive and Inductive Couplings investigates several kinds of electromagnetic coupling which inuence strongly the electric system operation. The electromagnetic coupling is a fundamental phenomenon that governs the behaviour of many electrical devices, but on the other hand can produce detrimental effects on their performances. In particular, electrical devices are frequently dominated by non-ideal parameters, attributable to circuital, geometrical or environmental issues. Electrical engineering deals with the possibility to reduce non-ideality as much as possible through appropriate design solutions and modelling analysis.

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Conejeros, Espíndola Sergio. "Estructura Electrónica de Sólidos Inorgánicos." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/131399.

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Los sulfuros de metales de transición exhiben una amplia variedad de propiedades eléctricas y magnéticas que los hacen interesantes tanto en el ámbito científico como en el de las aplicaciones tecnológicas. En este trabajo se estudia, utilizando cálculos ab intio, la estructura electrónica y las propiedades de un conjunto de calcogenuros, la mayoría sulfuros de cobre complejos, para intentar relacionar su estructura electrónica con las propiedades de transporte electrónico y magnéticas. En el primer capítulo se presenta una metodología muy simple para asignar estados de oxidación de metales de transición en compuestos cristalinos que consiste en el análisis conjunto de las energías de los orbitales de core y la población de la capa d de valencia obtenidas en un cálculo de bandas. El método se ha aplicado con éxito a los sulfuros de cobre para los cuales es difícil establecer estados de oxidación de manera fiable a partir de datos experimentales y se ha extendido a compuestos de plata, en particular para elucidar los estados de oxidación de los metales en algunos óxidos mixtos de cobre y plata. Paralelamente se han estudiado también las propiedades magnéticas y electrónicas de CuFeS2 y CuS, dos sulfuros de cobre con propiedades eléctricas y magnéticas complejas para los que se encuentran ciertos datos contradictorios en la literatura. En particular, para la covelina, CuS, se han estudiado aspectos de su estructura electrónica con la finalidad de analizar si las interacciones débiles d10-d10 juegan un papel importante o no en la transición estructural que sufre este compuesto a baja temperatura y para CuFeS2 el trabajo se ha centrado en la determinación de las constantes de acoplamiento magnético para intentar explicar la curva compleja de susceptibilidad magnética que se encuentra para este compuesto. En la presente tesis también se incluye un estudio en el que se intenta predecir si los sulfuros cuaternarios laminares AFeCuS2 con estructura tipo ThCr2Si2 son capaces de soportar litio, tal como lo hacen los sulfuros cuaternarios con estructura CaAl2Si2. En este estudio también se explica porqué no es estable la estructura de tipo CaAl2Si2 cuando se elimina todo el litio de la fase laminar LiFeCuS2. Por último, se presenta un estudio de la estructura electrónica de los calcogenuros TaS3, NbSe3 y TaSe3. El compuesto NbSe3 es un conductor metálico para el cual hay cierta controversia en la literatura sobre si en su estructura de bandas hay cuatro o cinco bandas cruzando el nivel de Fermi. A raíz de un experimento reciente mediante la técnica ARPES en el que se muestra, sin lugar a dudas, que este compuesto presenta cuatro bandas que cruzan el nivel de Fermi hemos realizado un estudio pormenorizado de sus estructura electrónica junto a la de TaS, y TaSe3 en el que se pone de manifiesto que realmente solo hay cuatro bandas cruzando el nivel de Fermi pero que, debido a la importancia de las interacciones débiles Se•••Se que no se describen correctamente en la teoría del funcional de la densidad en algunos cálculos puede llegar a aparecer una quinta banda cruzando el nivel de Fermi. In this thesis we have applied first principles electronic structure methods to study the electronic structure of several transition metal chalcogenides in order to establish the relation between their electronic structure and their electrical and magnetic properties. In the first chapter we develop a new strategy based on the simultaneous use of core orbital energies and valence d shell populations to establish oxidation states of transition metal atoms in complex solid state compounds. As a test case we have successfully applied this new method to copper sulfides and mixed copper-silver oxides. The second and third chapters are devoted to the study of the electronic structure of two copper sulphides, CuS and CuFeS2. For the first one, our analysis focuses on the role that weak d10•••d10 interactions may play in the structural phase transition exhibited by this compound, while for the latter our study deals with the evaluation of exchange coupling constants in order to understand its complex magnetic susceptibility curve. The thesis finishes with a chapter devoted to TaS3, NbSe3 y TaSe3, three pseudo 1D transition metal chalcogenides that have been extensively studied both from the theoretical and experimental points of views. Our main motivation has been the presentation of a recent ARPES study for NbSe3 where it is shown that there are only four bands crossing the Fermi level, a question that is unclear in the literature where in some cases the presence of a fifth band is suggested. Our study shows that indeed there are only four bands crossing the Fermi level, but that the weak Se•••Se interactions present in this structure, which are poorly described in DFT lead in some calculations to a fifth band crossing erroneously the Fermi level.

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Souley, Madougou Abdoul Majid. "Contribution à l'étude et à la commande d'un système de chauffage par induction polyphasé." Phd thesis, Toulouse, INPT, 2011. http://oatao.univ-toulouse.fr/18601/1/souley_madougou_partie_1_sur_2_2.pdf.

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Le chauffage par induction est un procédé qui consiste à plonger un matériau conducteur d’électricité dans un champ magnétique variable, ayant ainsi pour effet, la création de FEM donc de courants de Foucault dont la circulation élève la température du matériau par effet Joule. Ce mode de chauffage est déjà implanté industriellement dans de nombreux secteurs parmi lesquels des fonderies et s’intègre bien dans les processus de traitement des matériaux en raison de ses divers avantages. Il permet notamment, l’atteinte de densités de puissances très élevées dont la distribution peut être contrôlée. Il est ainsi possible d’obtenir des chauffages localisés ou de l’ensemble du matériau suivant le traitement désiré. Cette souplesse du contrôle des profils de chauffe et une forte puissance de chauffe requièrent traditionnellement l’usage de systèmes comportant plusieurs bobines. Leur caractérisation aussi précise que possible et le contrôle des courants des inducteurs sont nécessaires. L’étude présentée ici recense dans un premier temps, les quelques solutions existantes dont la puissance est réglée en déplaçant des culasses et/ou des écrans magnétiques, permettant de mieux répartir les champs magnétiques produits, afin de disposer du profil de chauffe souhaité mais pour une faible gamme de tôles. Les rares solutions qui s’intéressent au contrôle électrique sont orientés vers du chauffage monophasé. La transposition directe de ces commandes aux cas multi-bobines ne suffit pas à résoudre le problème dans son intégralité car les inducteurs se perturbent mutuellement. Nous nous sommes donc orientés vers une solution ambitieuse qui permet de s’affranchir de pièces mobiles et rend le système plus fiable, plus précis et lui confère plus de souplesse pour s’adapter à différents profils de chauffe et différentes largeurs de matériaux. Cette solution se base sur une méthode qui consiste à contrôler les profils de chauffe par la seule action sur les courants d’alimentation des inducteurs tout en maitrisant les échanges d’énergie entre les inducteurs fortement couplés. Cette solution est appliquée sur un prototype construit par EDF. Dans un premier temps, nous avons modélisé le système dans son ensemble tant du point de vue électrique et magnétique que thermique, afin de disposer d’un modèle global simplifié qui permet de mieux en étudier le comportement. Une procédure d’optimisation permet de générer les amplitudes et les phases des courants inducteurs pour différents profils de chauffe. Après une étape d’identification paramétrique, nous avons défini et implanté un modèle simplifié dans le logiciel PSim, qui nous fournit des délais de simulation relativement courts. Les résultats obtenus ont été ensuite comparés à des expérimentations en boucle ouverte tout d’abord, qui nous ont conduits à une étude de sensibilité des grandeurs du système aux variations paramétriques. Il nous a été possible de commander le système grâce à un FPGA dans lequel nous avons implanté une commande numérique pour le contrôle des courants des inducteurs en vue du chauffage en statique d’un disque de tôle pour différents profils de consigne. Nous avons ensuite amélioré nos modèles dans différentes directions, par la prise en compte du rayonnement et de la conduction thermique, en les transposant à un système plus complexe à six phases et avec une prise en compte du défilé des matériaux. L’extension du principe de l’induction multi-bobines de 3 à 6 phases a révélé de fortes perturbations harmoniques des courants des inducteurs. Notre travail a permis de maîtriser les harmoniques en choisissant judicieusement les angles de commande et de caractériser les pertes dans les onduleurs.

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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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Al, Sayari Naji Mohammed Awn sulaiman. "Dynamic analysis of cage rotor induction motor using harmonic field analysis and coupling inductances method." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/dynamic-analysis-of-cage-rotor-induction-motor-using-harmonic-field-analysis-and-coupling-inductances-method(8c0aebfc-2d74-427e-9448-f9667a6ca099).html.

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The work presented in this thesis involves the development of a new analytical method for predicting the transient behaviour of squirrel cage induction motors subjected to pulsating mechanical loads such as a reciprocating compressor. The objective of this project is to develop analysis that will better inform the subsequent design method for determining the rating of industrial induction motors driving an oscillatory load. The analytical approach used to determine the transient response of the motor is based upon the harmonic coupling inductance method which is capable of accommodating any stator winding arrangement used in industrial motor designs. The analytical work described in this thesis includes the response of an induction motor subjected to a general oscillating load in terms of the damping and synchronous torque components. These torque components can be used to determine the additional system inertia required to limit the motor speed and current oscillations to predetermined levels. The work further identifies the motor-load natural resonant frequency and demonstrates the potential issues when driving a general oscillatory load at or close to this frequency. The analytical model was cross-checked using software modelling in Matlab for an industrial squirrel cage induction motor driving a selection of compressor loads. The simulation results were finally correlated with a detailed experimental validation in the laboratory using a squirrel cage induction motor connected to a permanent magnet synchronous motor controlled electronically to simulate general oscillatory load.

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Jeong, Seung Hee. "Soft Intelligence : Liquids Matter in Compliant Microsystems." Doctoral thesis, Uppsala universitet, Mikrosystemteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-281281.

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Soft matter, here, liquids and polymers, have adaptability to a surrounding geometry. They intrinsically have advantageous characteristics from a mechanical perspective, such as flowing and wetting on surrounding surfaces, giving compliant, conformal and deformable behavior. From the behavior of soft matter for heterogeneous surfaces, compliant structures can be engineered as embedded liquid microstructures or patterned liquid microsystems for emerging compliant microsystems. Recently, skin electronics and soft robotics have been initiated as potential applications that can provide soft interfaces and interactions for a human-machine interface. To meet the design parameters, developing soft material engineering aimed at tuning material properties and smart processing techniques proper to them are to be highly encouraged. As promising candidates, Ga-based liquid alloys and silicone-based elastomers have been widely applied to proof-of-concept compliant structures. In this thesis, the liquid alloy was employed as a soft and stretchable electrical and thermal conductor (resistor), interconnect and filler in an elastomer structure. Printing-based liquid alloy patterning techniques have been developed with a batch-type, parallel processing scheme. As a simple solution, tape transfer masking was combined with a liquid alloy spraying technique, which provides robust processability. Silicone elastomers could be tunable for multi-functional building blocks by liquid or liquid-like soft solid inclusions. The liquid alloy and a polymer additive were introduced to the silicone elastomer by a simple mixing process. Heterogeneous material microstructures in elastomer networks successfully changed mechanical, thermal and surface properties. To realize a compliant microsystem, these ideas have in practice been useful in designing and fabricating soft and stretchable systems. Many different designs of the microsystems have been fabricated with the developed techniques and materials, and successfully evaluated under dynamic conditions. The compliant microsystems work as basic components to build up a whole system with soft materials and a processing technology for our emerging society.

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Huhn, Richard A. (Richard Andrew). "Computational study on the origins of asymmetric induction in Pd-catalyzed cross-coupling reactions and suggestions for improvements thereupon." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/42916.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2008. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. Includes bibliographical references. The origins of asymmetric induction in the Suzuki-Miyaura cross coupling reaction are investigated computationally with density functional theory. Monophosphine-bound palladium complexes are analyzed in the context of oxidative addition to aryl halides, and ligands are explored in terms of steric and electronic effects relevant to oxidative addition. As one of the most successful ligands to date for the asymmetric Suzuki reaction, KenPhos is given substantial attention and subjected to detailed structural analysis. The analysis leads to proposals for new ligands that may enhance the asymmetry of oxidative addition, and some initial synthetic work in that capacity is presented Thesis Supervisor: Professor Stephen L. Buchwald by Richard A. Huhn. S.M.

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Richer, Susanne [Verfasser], David P. [Akademischer Betreuer] DiVincenzo, and Christoph [Akademischer Betreuer] Stampfer. "Design of an inductively shunted transmon qubit with tunable transverse and longitudinal coupling / Susanne Richer ; David P. DiVincenzo, Christoph Stampfer." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1185442006/34.

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KANNAMKUMARATH, SASI S. "TRACE ELEMENTAL SPECIATION USING CHROMATOGRAPHY/CAPILLARY ELECTROPHORESIS COUPLED TO INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY FOR FOOD, PHARMACEUTICAL AND ENVIRONMENTAL ANALYSIS." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1085673299.

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Caillierez, Antoine. "Etude et mise en oeuvre du transfert de l'énergie électrique par induction : application à la route électrique pour véhicules en mouvement." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLC010/document.

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La transmission d’énergie par induction est devenue un sujet extrêmement porteur compte tenu du contexte géopolitique et environnemental du moment ; ainsi que des possibilités technologiques. Les enjeux de l’alimentation électrique d’un véhicule en roulant sont importants : réduction de la taille de la batterie embarquée, du poids et du coût du véhicule, limitation des importations de cellules de batteries et réduction des importations pétrolières au profit d’investissements locaux et extension du rayon d’action des véhicules électriques voire hybrides rechargeables pouvant aller d’un simple bonus à un rayon d’action infini selon le dimensionnement de l’infrastructure.La solution développée utilise le vecteur magnétique. Elle fait donc appel à des bobines faiblement couplés qui impliquent de fortes inductances de fuite et des chutes de tensions associées hors du commun. Un nouveau type de convertisseur « continu-continu » a été imaginé afin de répondre à ces contraintes. Celui-ci se fonde sur le concept de symétrie ; l’analyse détaillée basée sur les diagrammes de Fresnel, a conduit à l’élaboration d’un fonctionnement particulier qui a été appelé la « recopie de tension ». Le prototype réalisé fonctionne avec un entrefer réaliste de 15 centimètres, une tolérance au décentrage de +/-50% sur l’axe longitudinal, une tension de sortie stable avec de faibles pertes malgré d’importantes variations de couplage. Le tout sans aucune communication entre la partie au sol et la partie mobile. Ces résultats permettent d’envisager sérieusement un fonctionnement en roulant.Celui-ci nécessite de pouvoir séquencer l’alimentation d’une multitude de bobines de petite taille enfouies sous la chaussée, au bon moment et à la bonne position. La mise en court-circuit résonnant des bobines inactive permet d’utiliser la mesure des courants pour déterminer précisément l’instant d’activation de la bobine suivante. Cette solution originale, qui s’affranchi de tout capteur de position, conserve la propriété de recopie de tension et le principe de dimensionnement développés dans la première partie Inductive power transfer has become a flourishing subject, considering the current geopolitical and environmental situation and the new technological possibilities. The electric road may lead to important and valuable consequences: extended range for electric vehicles and even hybrids, from a simple bonus to an infinite range, depending on the infrastructure set up, down-sized on-board batteries, reduction of the weight and cost of the vehicle and lowered importations of both battery cells and oil for the benefit of local investments .The solution developed uses a magnetic medium for the transfer. Therefore, it involves loosely coupled coils, implying inevitably strong leakage inductances and outstanding associated voltage drops. A new type of DC-DC converter was imagined to answer those issues. It is based on the concept of symmetry; a detailed analysis conducted with phasor diagrams leads to a specific working principle, which has been named the “voltage copying”. Thus, the DC/DC converter designed works with a realistic air-gap of 15 centimeters, a longitudinal tolerance to displacement up to +/-50% and a stable output voltage with low losses despite large coupling variations. And it all works without any communication between the ground part and the mobile part. These results make a dynamic charging seriously worth investigating.It requires to sequence the power supply of a multitude of small coils buried beneath the road surface, at the right time and for the right position. Putting inactive coils in a resonant short-circuit mode enables to use current measures to precisely detect the switching time from one coil to the next. This original solution, free of any position sensor, does not prevent the specific “voltage copying” property and the design principles developed in the first part

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Haider, Syed. "Enhanced gel electrophoresis (GE) and inductively coupled plasma-mass spectrometry (ICP-MS) based methods for the identification and separation of proteins and peptides." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/10279.

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The main focus of the PhD study was to develop new gel electrophoresis and ICP-MS based methods to analyze a wide variety of the bio-molecules such as proteins, phosphoproteins and metalloproteins etc. The tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (tricine-SDS-PAGE) method is commonly used to resolve low molecular mass proteins, however, it requires a high percentage gel and a very complicated procedure to achieve this separation. This study describes a modification to tricine-SDS-PAGE to make it more effective for the separation of smaller proteins and for coupling to ICP-MS. The modified method employs low percentage PAGE gels and low reagent concentrations that provide efficient separations, good quantitation and low matrix levels that are compatible with ICP-MS. This modified method was applied to analyze phosphopeptides. Phosphopeptides are very small in size and difficult to separate using the other techniques such as Laemmli SDS-PAGE, original tricine-SDS-PAGE, immobilized metal affinity chromatography (IMAC), size exclusion chromatography (SEC) etc. In this study a simplified procedure is described based on modifying the original tricine-SDS-PAGE method. A comparative study showed that this modified method successfully resolved a digest mixture of very low to high molecular mass phosphopeptides/peptides. In off-line coupling of this method with ICP-MS, much better recoveries of the peptides from the gel were obtained as compared to traditional methods which indicate the compatibility of this modified method for quantitative studies. An on-line coupling of the modified system with ICP-MS was also demonstrated and it was applied for the separation, detection and quantification of phosphopeptides. Another application of this modified system was the separation of serum proteins. Blood serum contains five major protein groups i.e., albumin, alpha-1 globulin, alpha-2 globulin, beta globulin and gamma globulin. The separation of these five major proteins in a single gel is difficult to achieve using traditional methods. The modified system was shown to be superior for the separation of these serum proteins in a 7% (m/v) native-PAGE gel and a cellulose acetate membrane. A further study was carried out into controlling the factors that cause metal loss and protein fragmentation in SDS-PAGE. Using a reducing sample buffer, and heating to high temperatures (90-100ºC) in alkaline or acidic conditions may cause protein fragmentation and decrease the metal binding affinity. 70ºC was found suitable to prepare the sample at neutral, alkaline or acidic pH as no fragmentation observed. To prevent metal loss, the binding constant (log K) values of metal-amino acids, play the major role. Those metals which have high binding affinities with the amino acids in proteins can also be affected by the variation of the pH so prior information about pH to maintain the binding constant values is essential to minimize metal loss. This was observed in the loss of zinc, and to a lesser extent copper from human serum albumin (HSA) as measured by inductively coupled plasma mass spectrometry (ICP-MS). The method described above was applied for the separation and quantification of the serum proteins obtained from age-related macular degeneration (AMD) patients (where the AMD patients were from Moorfields Eye Hospital, London). Zn and Cu were quantified employing external calibration. Zn concentration showed variation whilst Cu did not show any significant variations in samples from AMD patients. A brief study of the interaction of cisplatin and oxaliplatin with HSA and transferrin was also performed. Cisplatin bound much faster than oxaliplatin with HSA. After 24 hours incubation, cisplatin showed a decrease in signal intensity which indicates that cisplatin binding decreases with time. Cisplatin binding with transferrin as compared to HSA was not significant, which could be the result of unstable Pt-transferrin complex formation. Oxaliplatin did not show high binding to either protein, perhaps due to the presence of the bulky, non polar DACH ligand.

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Eustache, Patrick. "Utilisation d'un environnement éléments finis (S. I. C. ) pour le traitement couple en magnéto-thermique." Grenoble INPG, 1995. https://hal.science/tel-01570156.

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L'objectif de cette étude est de développer dans l'environnement éléments finis S. I. C. (Système Interactif de Conception), des outils informatiques permettant le traitement de phénomènes physiques couplés. Nous avons étudié en particulier les spécificités du couplage magnéto-thermique. Nous présentons les problèmes posés, puis en nous appuyant sur une application de magnéto-formage, nous justifions les solutions que nous avons programmées. En effet, ce type de couplage comporte de nombreuses difficultés. Tout d'abord, il faut disposer de tous les outils et les modèles permettant une représentation des lois de comportement magnétiques et thermiques. Ensuite, la modélisation des déplacements de pièces avec contact requiert l'utilisation de méthodes adaptées. Pour le déplacement, nous utilisons différentes méthodes de remaillages ou "assimilées" et pour le contact thermique, nous avons développé une méthode originale d'échanges entre éléments linéiques. Afin de faire coexister et communiquer différents modèles physiques, nous avons opté pour une méthode de "couplage indirect" (où les résolutions éléments finis de chaque discipline sont enchaînées successivement). Cette méthode permet de conserver les acquis de chaque discipline et de respecter leurs exigences et évolutions. De plus, nous montrons qu'elle est bien adaptée à une structuration des données sous forme d'objets. Les outils génériques ainsi réalisés ont permis le développement d'un module magnéto-themique. Nous l'avons utilisé pour étudier un procédé industriel complexe de formage de tubes d'acier chauffés par induction The aim of this study is to develop software tools allowing the treatment of coupled physical phenomena in a finite élément environment called S. I. C. (interactive design system). The specificities of the magnéto-thermal coupling in particular are studied. First the encountered problems are presented and then the chosen and programmed solutions are justified through an application of shaping by magnetic heating. Indeed, such a coupling involves many difficulties. First of ail, the tools and the models allowing the représentation of the magnetic and thermal phenomena need to be at one's disposai. Then, the modelling of moving parts with contacts requires the use of well adapted methods. For the movement, différent kinds of re-mesh or "assimilated" are used, while for the thermal contact, an original method of exchange between line éléments has been developed. In order to make différent physical models coexist and communicate among themselves, a "direct coupling" method is used (in such a method, the finite élément solving of each field are successively chained). This method allows to keep the vested interests of each field and to respect their needs and évolutions (This method allows to respect the partieularities of each field as well as their needs and évolutions). Moreover, this method has proved to be well adapted to an object data structuring. The generic tools thus realised hâve allowed the development of a magnéto-thermal module. This module has been used to study a sophisticated industrial process of shaping iron tubes by magnetic heating

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Hudák, Ondřej. "Laboratorní soustrojí s asynchronním a stejnosměrným motorem." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219757.

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The work addresses the design and implementation of a universal laboratory workstation designed to teach a course on electrical drives. Workplace will be formed sets consisting of DC motor with permanent magnet on a 400W power supply voltage of 24V and induction motor with 180W power on 3x24V. The engines are connected through a flexible shaft coupling. The asynchronous motor is located on the extended shaft resolver for scanning speed and rotor position. Both engines will be supplied from the transistor inverters. The workplace will be designed for maximum clearness and resistance to damage by improper handling.

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Dolisy, Bastien. "Étude d’un moteur supraconducteur à flux axial avec une transmission magnétique supraconductrice intégrée." Electronic Thesis or Diss., Université de Lorraine, 2015. http://www.theses.fr/2015LORR0079.

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Nous proposons l’étude d’une machine supraconductrice à flux axial composée d’un stator bobiné en cuivre et d’un inducteur avec des solénoïdes supraconducteurs à hautes températures critiques (HTc). Ce type de machine est adapté pour des applications de fortes puissances (plusieurs MW) avec de faibles vitesses de rotation (quelques centaines de tr/min), comme la propulsion de navire. Un accouplement magnétique, intégré au moteur, est utilisé pour transmettre le couple de l’inducteur supraconducteur vers la charge à température ambiante sans contact. On peut ainsi se passer des « torques tubes » qui sont habituellement présents dans les moteurs supraconducteurs pour relier mécaniquement l’inducteur à la charge et ainsi réduire les pertes thermiques par conduction. De plus, les accouplements magnétiques offrent une protection naturelle contre les surcharges mécaniques. Pour évaluer les performances de la solution proposée, nous avons développé un modèle analytique en 3D prenant en compte le comportement non linéaire des supraconducteurs en fonction du champ magnétique appliqué et de la température de fonctionnement. Ce modèle est ensuite intégré dans un processus de dimensionnement utilisant un algorithme génétique multi objectifs. Les résultats de cette optimisation montrent un gain en compacité (machine avec accouplement magnétique) 2 à 3,5 fois plus importants par rapport à des machines conventionnelles. Un prototype de machine supraconductrice à flux axial avec accouplement magnétique intégré est aussi réalisé. La conception, la fabrication et les tests sont présentés dans ce manuscrit. Tous les résultats sont validés par des calculs par éléments finis The study of an axial-field high temperature superconducting (HTS) motor for applications requiring high torque densities is proposed. The HTS motor consists of a stator with copper winding and an inductor with superconducting coils. A HTS magnetic coupler is used as a part of the system, to transmit the torque from the HTS motor to the load. This solution is a good alternative to the usually used torques tubes as it results in the reduction of conduction thermal losses and offers an intrinsic protection against overloads. To evaluate the performance of the studied device, a 3D electromagnetic analytical model has been developed. This model takes into account the dependence on the applied magnetic field and temperature of the HTS material. Finally, a genetic algorithms optimization of the studied device is carried out to find the optimum geometric dimensions. The results show that the proposed solution (machine with magnetic coupling) is about 2 to 3,5 times more compact than a conventional machine drive solution. An axial-field HTS motor with integrated magnetic coupling has been also designed, constructed and tested. The test results have been checked by 3D finite element computations

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Dolisy, Bastien. "Étude d’un moteur supraconducteur à flux axial avec une transmission magnétique supraconductrice intégrée." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0079/document.

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Nous proposons l’étude d’une machine supraconductrice à flux axial composée d’un stator bobiné en cuivre et d’un inducteur avec des solénoïdes supraconducteurs à hautes températures critiques (HTc). Ce type de machine est adapté pour des applications de fortes puissances (plusieurs MW) avec de faibles vitesses de rotation (quelques centaines de tr/min), comme la propulsion de navire. Un accouplement magnétique, intégré au moteur, est utilisé pour transmettre le couple de l’inducteur supraconducteur vers la charge à température ambiante sans contact. On peut ainsi se passer des « torques tubes » qui sont habituellement présents dans les moteurs supraconducteurs pour relier mécaniquement l’inducteur à la charge et ainsi réduire les pertes thermiques par conduction. De plus, les accouplements magnétiques offrent une protection naturelle contre les surcharges mécaniques. Pour évaluer les performances de la solution proposée, nous avons développé un modèle analytique en 3D prenant en compte le comportement non linéaire des supraconducteurs en fonction du champ magnétique appliqué et de la température de fonctionnement. Ce modèle est ensuite intégré dans un processus de dimensionnement utilisant un algorithme génétique multi objectifs. Les résultats de cette optimisation montrent un gain en compacité (machine avec accouplement magnétique) 2 à 3,5 fois plus importants par rapport à des machines conventionnelles. Un prototype de machine supraconductrice à flux axial avec accouplement magnétique intégré est aussi réalisé. La conception, la fabrication et les tests sont présentés dans ce manuscrit. Tous les résultats sont validés par des calculs par éléments finis The study of an axial-field high temperature superconducting (HTS) motor for applications requiring high torque densities is proposed. The HTS motor consists of a stator with copper winding and an inductor with superconducting coils. A HTS magnetic coupler is used as a part of the system, to transmit the torque from the HTS motor to the load. This solution is a good alternative to the usually used torques tubes as it results in the reduction of conduction thermal losses and offers an intrinsic protection against overloads. To evaluate the performance of the studied device, a 3D electromagnetic analytical model has been developed. This model takes into account the dependence on the applied magnetic field and temperature of the HTS material. Finally, a genetic algorithms optimization of the studied device is carried out to find the optimum geometric dimensions. The results show that the proposed solution (machine with magnetic coupling) is about 2 to 3,5 times more compact than a conventional machine drive solution. An axial-field HTS motor with integrated magnetic coupling has been also designed, constructed and tested. The test results have been checked by 3D finite element computations

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Adabi, Firouzjaee Jafar. "Remediation strategies of shaft and common mode voltages in adjustable speed drive systems." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/39293/1/Jafar_Adabi_Firouzjaeel_Thesis.pdf.

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AC motors are largely used in a wide range of modern systems, from household appliances to automated industry applications such as: ventilations systems, fans, pumps, conveyors and machine tool drives. Inverters are widely used in industrial and commercial applications due to the growing need for speed control in ASD systems. Fast switching transients and the common mode voltage, in interaction with parasitic capacitive couplings, may cause many unwanted problems in the ASD applications. These include shaft voltage and leakage currents. One of the inherent characteristics of Pulse Width Modulation (PWM) techniques is the generation of the common mode voltage, which is defined as the voltage between the electrical neutral of the inverter output and the ground. Shaft voltage can cause bearing currents when it exceeds the amount of breakdown voltage level of the thin lubricant film between the inner and outer rings of the bearing. This phenomenon is the main reason for early bearing failures. A rapid development in power switches technology has lead to a drastic decrement of switching rise and fall times. Because there is considerable capacitance between the stator windings and the frame, there can be a significant capacitive current (ground current escaping to earth through stray capacitors inside a motor) if the common mode voltage has high frequency components. This current leads to noises and Electromagnetic Interferences (EMI) issues in motor drive systems. These problems have been dealt with using a variety of methods which have been reported in the literature. However, cost and maintenance issues have prevented these methods from being widely accepted. Extra cost or rating of the inverter switches is usually the price to pay for such approaches. Thus, the determination of cost-effective techniques for shaft and common mode voltage reduction in ASD systems, with the focus on the first step of the design process, is the targeted scope of this thesis. An introduction to this research – including a description of the research problem, the literature review and an account of the research progress linking the research papers – is presented in Chapter 1. Electrical power generation from renewable energy sources, such as wind energy systems, has become a crucial issue because of environmental problems and a predicted future shortage of traditional energy sources. Thus, Chapter 2 focuses on the shaft voltage analysis of stator-fed induction generators (IG) and Doubly Fed Induction Generators DFIGs in wind turbine applications. This shaft voltage analysis includes: topologies, high frequency modelling, calculation and mitigation techniques. A back-to-back AC-DC-AC converter is investigated in terms of shaft voltage generation in a DFIG. Different topologies of LC filter placement are analysed in an effort to eliminate the shaft voltage. Different capacitive couplings exist in the motor/generator structure and any change in design parameters affects the capacitive couplings. Thus, an appropriate design for AC motors should lead to the smallest possible shaft voltage. Calculation of the shaft voltage based on different capacitive couplings, and an investigation of the effects of different design parameters are discussed in Chapter 3. This is achieved through 2-D and 3-D finite element simulation and experimental analysis. End-winding parameters of the motor are also effective factors in the calculation of the shaft voltage and have not been taken into account in previous reported studies. Calculation of the end-winding capacitances is rather complex because of the diversity of end winding shapes and the complexity of their geometry. A comprehensive analysis of these capacitances has been carried out with 3-D finite element simulations and experimental studies to determine their effective design parameters. These are documented in Chapter 4. Results of this analysis show that, by choosing appropriate design parameters, it is possible to decrease the shaft voltage and resultant bearing current in the primary stage of generator/motor design without using any additional active and passive filter-based techniques. The common mode voltage is defined by a switching pattern and, by using the appropriate pattern; the common mode voltage level can be controlled. Therefore, any PWM pattern which eliminates or minimizes the common mode voltage will be an effective shaft voltage reduction technique. Thus, common mode voltage reduction of a three-phase AC motor supplied with a single-phase diode rectifier is the focus of Chapter 5. The proposed strategy is mainly based on proper utilization of the zero vectors. Multilevel inverters are also used in ASD systems which have more voltage levels and switching states, and can provide more possibilities to reduce common mode voltage. A description of common mode voltage of multilevel inverters is investigated in Chapter 6. Chapter 7 investigates the elimination techniques of the shaft voltage in a DFIG based on the methods presented in the literature by the use of simulation results. However, it could be shown that every solution to reduce the shaft voltage in DFIG systems has its own characteristics, and these have to be taken into account in determining the most effective strategy. Calculation of the capacitive coupling and electric fields between the outer and inner races and the balls at different motor speeds in symmetrical and asymmetrical shaft and balls positions is discussed in Chapter 8. The analysis is carried out using finite element simulations to determine the conditions which will increase the probability of high rates of bearing failure due to current discharges through the balls and races.

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Calet, Serge. "Chimie organometallique d'heterocycles a trois chainons (carbonylation, desulfuration, couplage)." Paris 6, 1987. http://www.theses.fr/1987PA066292.

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Beckstein, Pascal. "Methodenentwicklung zur Simulation von Strömungen mit freier Oberfläche unter dem Einfluss elektromagnetischer Wechselfelder." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-232474.

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Im Bereich der industriellen Metallurgie und Kristallzüchtung treten bei zahlreichen Anwendungen, wo magnetische Wechselfelder zur induktiven Beeinflussung von leitfähigen Werkstoffen eingesetzt werden, auch Strömungen mit freier Oberfläche auf. Das Anwendungsspektrum reicht dabei vom einfachen Aufschmelzen eines Metalls in einem offenen Tiegel bis hin zur vollständigen Levitation. Auch der sogenannte RGS-Prozess, ein substratbasiertes Kristallisationsverfahren zur Herstellung siliziumbasierter Dünnschichtmaterialien, ist dafür ein Beispiel. Um bei solchen Prozessen die Interaktion von Magnetfeld und Strömung zu untersuchen, ist die numerische Simulationen ein wertvolles Hilfsmittel. Für beliebige dreidimensionale Probleme werden entsprechende Berechnungen bisher durch eine externe Kopplung kommerzieller Programme realisiert, die für Magnetfeld und Strömung jeweils unterschiedliche numerische Techniken nutzen. Diese Vorgehensweise ist jedoch im Allgemeinen mit unnötigem Rechenaufwand verbunden. In dieser Arbeit wird ein neu entwickelter Methodenapparat auf Basis der FVM vorgestellt, mit welchem sich diese Art von Berechnungen effizient durchführen lassen. Mit der Implementierung dieser Methoden in foam-extend, einer erweiterten Version der quelloffenen Software OpenFOAM, ist daraus ein leistungsfähiges Werkzeug in Form einer freien Simulationsplattform entstanden, welches sich durch einen modularen Aufbau leicht erweitern lässt. Mit dieser Plattform wurden in foam-extend auch erstmalig dreidimensionale Induktionsprozesse im Frequenzraum gelöst.

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chao, heng-sheng, and 趙恆生. "Design and Study of Coupling Circuit for Inductive Charger." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/47298050921957360884.

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碩士 中原大學 電機工程研究所 89 Abstract The main purpose of this thesis is to study a wireless power transmission of inductive charger utilizing inductive coupling theorem. Inductive charging technology offers a safe and reliable method for battery charging. With inductive charging, the energy is transferred via magnetic induction rather than ohmic contact. In such a system, one core is in charging side and the other is in battery side. This thesis first studies how to select converter circuits and how to design input and output components, and then, coupling efficiencies for different transformer core configurations and the effects of gaps between the primary core and the secondary core are studied. Finally, the inductive charger is analyzed and discussed.

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Liu, Yu-Hsiu, and 劉禹秀. "Inductive Coils Coupling and Circuit Analysis of Wireless Recharging." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/48976959476583191551.

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碩士 國立臺灣大學 光電工程學研究所 99 Safety and convenience become one of the considering factors of consumption with the prevalence of portable electrical products nowadays. Besides disorderliness and inconvenience, traditional recharging devices with cables still have many problems such as electrocution, fire caused by electricity, etc. In order to solve these problems, development of wireless recharging technology brings in a brand new design concept. We can recharge portable electrical devices safely and conveniently by just putting them on the recharging platform. However, the main difficulty is the low efficiency of electric power transfer without cables as transferring media. Therefore, in the thesis, we analyze the inductive circuits of wireless recharging device proposed by Wireless Power Consortium, and derive the efficiency of effective power transfer between each circuit layer and use electromagnetic simulation software—Maxwell 3D—to simulate coupling coefficients of two inductive coils, which are key points of electric power transfer. The part of circuit analysis is about transmitting and receiving circuit, we analyze the power transfer efficiency of two resonant circuits which have complex impedances in the frequency domain. Then we simulate two coil structures—vertical helix coils and horizontal helix coils, incorporated with additionally auxiliary magnetic shieldings to improve coupling coefficients, to compare effects of electromagnetic coupling analyzed by Maxwell 3D software. Finally, we wind two structures made by coils mentioned above to measure the coupling coefficients and calculate the power transfer efficiency of simplified inductive circuit for coils with magnetic shieldings.

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Je-BinSu and 蘇哲彬. "Contactless Inductive Power Transmission Track for ElectricVehicles: Implementation of Interlaced-Winding Weaving-TypeArray Block Inductive Coupling System." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/83408167873602761433.

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碩士 國立成功大學 電機工程學系碩博士班 98 This thesis investigates the inductive coupling system of contactless inductive power transmission track, and the main feature is utilizing interlaced-winding weaving-type coupling structure to build a power transmission track for vehicles. At first, this thesis will present different coupling structures and to explore feasibility of interlaced-winding weaving- type coupling structure. In order to improve the efficiency of power transmission, the system will use double-winding selective mechanism. The microcontroller sending message to primary side via RF module depends on energy of secondary side picked up. According to the message, the primary side will choose correct coil mode. At the same time, the host can communicate with microcontroller by RS-485 communications architecture. Finally, experimental results show that the highest power transmission efficiency of the power transmission track is 53.6% under 6.5mm air-gap.

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Huang, Po-Han, and 黃柏翰. "Wireless Power Transmission Traverses Metal Tubular using Capacitive and Inductive Coupling." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/r45q6g.

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碩士 國立臺灣科技大學 電機工程系 107 This thesis applied a wireless measure to transfer power across a tube-shape metal barrier by combining with electric field coupling and magnetic field coupling. The electric field coupling is set up by two copper films with isolated layers which round at the top and bottom parts of the metal tube. The tube wall between the top and bottom ends acts as the primary side of the magnetic field coupling and a receiving coil with high-permeability core deployed inside the tube acts as the secondary winding. The wireless power transfer is accomplished by an H-bridge dc/ac converter and a series-series resonant structure which contains the mentioned coupling mechanism. Compared to previous study in which plate mental barrier was under considered, the tube application is not suffered from skin effect due to the round wall construction. A magnetic field analysis method is proposed for metal tube, and relative equations are derived as well. In order to consider the skin effect of the mental tube wall, the Electromagnetic field of the tube wall is analyzed with ANSYS Maxwell 3D simulation software, and the drive circuit is also simulated with MATLAB/SIMULINK simulation software to evaluate the performance of the proposed system. Two metal tubes with different diameters and one metal plate are used as the barriers for testing, and a prototype based on digital signal processor (TMS320F28069) is set up to demonstrate the experimental results of this study.

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Dissertations / Theses on the topic 'Inductive coupling'

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