Dans ce travail, nous avons réalisé et validé le fonctionnement d’une nouvelle structure de moteur supraconducteur composé d’un inducteur supraconducteur et d’un induit en cuivre. La structure originale de ce moteur est basée sur le principe de modulation de flux par l’utilisation d’un écran supraconducteur massif. Après avoir modélisé la machine par éléments finis, la construction du moteur a été achevée avec succès, une étape très délicate présentant de nombreuses difficultés. Les résultats montrent, non seulement la faisabilité technique de la machine, mais également son bon fonctionnement. Les essais, à vide, en court-circuit et en charge nous ont permis de déterminer les éléments d’un modèle de Ben-Eschenburg de ce moteur. En conclusion l’objectif de ce projet a été atteint avec succès / In this work, we have achieved and validated a new superconductor motor structure, consisting of a superconducting inductor and of an armature of copper. The original structure of this motor is based on the principle of flux modulation by the use of a bulk superconductor screen. After modeling the machine by finite elements, the construction of the engine has been achieved successfully, a very delicate stage with many difficulties. The results show not only the technical feasibility of the machinery, but also its good operation. The experiments with and without load, and the one under short circuit, allowed to determine the elements of the Ben-Eschenburg model for this machine. As conclusion, the aim of the project was successfully achieved

The work described in this thesis is aimed at developing a novel piezoelectric cantilever energy harvesting circuit, so that more energy can be obtained from a particular piezoelectric harvester than is possible using conventional circuits. The main focus of the work was to design, build and test a proof of principle system, and not a commercial version, so as to determine any limitations to the circuit. The circuit functions by cancelling the capacitive output reactance of the piezoelectric harvester with a simulated inductance, and is based on an idea proposed by Qi in 2011. Although Qi's approach demonstrated that the circuit could function, the system proved too lossy, and so a less lossy version is attempted here. Experimental and software simulations are provided to verify the theoretical predictions. A prototype amplified inductor circuit was simulated and tested. From the simulation results, although harmonic current losses were found in the circuit, it was found that the circuit should produce an amplified effective inductance and a maximum output power of 165mW. The effective inductance is derived from the voltage across the 2H inductor, and this voltage is amplified and applied to the circuit via an inverter, to provide an extra simulated inductance, so that the overall inductance can be resonated with the piezoelectric harvester output capacitance. Hence the capacitive impedance of the harvester is nearly cancelled. The study and analysis of the amplified inductor circuit was carried out for a single cantilever harvester. Both open loop and closed loop testing of the system were carried out. The open loop test showed that the concept should function as predicted. The purpose of the closed loop test was to make the system automatically adjust for different resonance frequencies. The circuit was tested at 52Vpp inverter output voltage, and demonstrated a harvested power of 145.5mW. Experimental results show that the harvester output power is boosted from 8.8mW as per the manufacturer data sheet to 145.5mW (16.5 times). This is approximately double the power available using circuits described in the literature.

Objetivando reduzir o manejo em protocolos de inseminação artificial em tempo fixo (IATF), quatro experimentos foram realizados para avaliar a dinâmica folicular (Experimentos 1A e 1B) e a taxa de concepção (TC; Experimentos 2, 3 e 4) em vacas de corte tratadas com Cipionato (CE) ou Benzoato (BE) de estradiol como indutores da ovulação. No Experimento 1A, 51 animais receberam 2mg de BE e um dispositivo intravaginal de progesterona (DIB) novo no D0. No D8, os animais foram distribuídos entre quatro tratamentos (G-BE8, G-BE8,5, G-BE9 e G-CE8). Neste dia, o dispositivo foi removido, 0,530mg de Cloprostenol e 300UI de eCG foram administrados [manhã (M) no G-BE8, G-CE8 e G-BE9; tarde (T) no G-BE8,5]. As vacas do G-CE8 receberam 1,0mg de CE, as do G-BE8 e G-BE8,5 receberam 1,0mg de BE na retirada do DIB, e aquelas do G-BE9 receberam 1,0mg de BE 24 horas após. Análises ultra-sonográficas foram realizadas a cada 12 horas, da retirada do dispositivo até a ovulação. Foram utilizados os PROC GLM e GLIMMIX do SAS para análise estatística. Nos experimentos não foram observadas interações. Os resultados para G-BE8, G-CE8, G-BE8,5 e G-BE9 foram, respectivamente: diâmetro do folículo ovulatório (FO;11,9±0,4b; 14,3±0,4a; 12,3±0,4b; e 13,3±0,abmm; P=0,01), taxa de ovulação (TO;100%; 90,0%; 100% e 91,7%; P=0,99] e intervalo retirada/ovulação (IRO;58,3±2,1b; 72,0±2,0a; 57,6±1,3b e 72,0±0,0ah; p<0,001). No Experimento 1B (n=35), foi utilizado arranjo fatorial 3x3 [números de uso do DIB vs protocolos de indução da ovulação (PIO)]. No D0, os animais foram divididos em três grupos [DIB novo (DIBN), usado 8 (DIB8) e 16 dias (DIB16)]. Na retirada do DIB, os animais foram redistribuídos para os PIOs descritos no Experimento 1A (exceto G-BE8). Os resultados para G-CE8, G-BE8,5 e G-BE9 foram, respectivamente: FO (14,0±0,6; 13,8±0,6 e 13,6±0,5mm; P=0,88), TO [81,8%; 83,3% e 83,3%; P=0,93] e IRO (72,0±2,0a; 59,6±1,6b e 73,2±1,2ah; p<0,01). Os resultados para DIBN, DIB8 e DIB16 foram respectivamente: FO (13,8±0,7; 13,5±0,6 e 13,9±0,5mm; P=0,99), TO [90,9%; 83,3% e 75,0%; P=0,93] e IRO (74,4±1,6a; 72,0±0,0ab e 68,0±2,0bh; P=0,02). No Experimento 2, 584 animais foram alocados em fatorial 3x2 [PIO (CE8, BE8,5 e BE9) e período de IATF (IATF-M ou IATF-T)], utilizando DIBN. Não houve diferença na TC: CE8 (57,5%), BE9 (59,9%) e BE8,5 (49,5%; P=0,09) e IATF M (56,6%) ou T (54,8%; P=0,66). No Experimento 3, 521 vacas foram divididas como no Experimento 2, porém com DIB8. Não houve diferença na TC nos PIOs: CE8 (47,3%), BE9 (53,3%) e BE8,5 (55,2%; P=0,10). Porém, houve diferença na TC para IATF-M (60,7%) ou IATF-T (48,3%; P=0,01). No Experimento 4, 1192 vacas foram distribuídas em fatorial 2x3x2 (DIBN e DIB8; BE8,5, BE9 e CE8; IATF-M e IATF-T). Não houve diferença na TC para: IATF-M (64,6%) ou IATF-T (59,5%; P=0,06) e PIOs; CE8 (65,8%), BE9 (61,8%) e BE8,5 (58,6%; P=0,12). Entretanto, houve diferença na TC (P=0,04) para uso do DIB; DIBN (65,0%) e DIB8 (59,4%). Esses resultados indicam que os PIOs apresentam mesma eficiência. Com DIB8, a IATF-T apresentou menor TC e o uso de DIB8 resultou em menor TC do que DIBN. / Aiming to minimize the number of handling during protocols for fixed-time artificial insemination (FTAI), four experiments were performed to evaluate the follicular dynamics (Experiments 1A and 1B) and conception rate (CR; Experiments 2, 3 e 4) in beef cows treated with estradiol cypionate (EC) or benzoate (EB) as ovulation inducers. In Experiment 1A, 51 animals received 2mg of EB and a new intravaginal progesterone device (DIB) on D0. On D8, animals were assigned into four treatments (G-EB8, G-EB8.5, G-EB9 and G-EC8). On the same day, the device was removed, 0.530mg of Cloprostenol and 300UI of eCG were administered [morning (AM) - G-EB8, G-EC8 and G-EB9; afternoon (PM) - G-EB8.5]. Cows of G-EC8 received 1.0mg of EC, while G-EB8 and G-EB8.5 received 1.0mg of EB at DIB removal, and those of G-EB9 received 1.0mg of EB 24h later. Ultrasonography was performed every 12h from DIB removal until ovulation. Statistical analysis was performed using PROC GLM and PROC GLIMMIX (SAS). No interactions were observed between treatments. Results of G-EB8, G-EC8, G-EB8.5 and G-EB9 were, respectively: diameter of ovulatory follicle (OF;11.9±0.4b; 14.3±0.4a; 12.3±0.4b; and 13.3±0.6abmm; P=0.01), ovulation rate (OR; 100%; 90.0%; 100% and 91.7%; P=0.99) and interval between device removal-ovulation (IRO; 58.3±2.1b; 72.0±2.0a; 57.6±1.3b and 72.0±0.0ah; p<0.001). Experiment 1B (n=35) was performed using a fatorial design 3x3 [DIB reutilization and ovulation inducer (OI)]. On D0, animals were allocated into three groups [new DIB (DIBN), used 8 (DIB8) and 16 days (DIB16)]. At DIB removal, animals were reallocated into the same OIs described on Experiment 1A, except by the G-EB8. The results of G-EC8, G-EB8.5 and G-EB9 were, respectively: OF (14.0±0.6; 13.8±0.6 and 13.6±0.5mm; P=0.88), OR [81.8%; 83.3% and 83.3%; P=0.93], and IRO (72.0±2.0a; 59.6±1.6b and 73.2±1.2ah; p<0.01). Results of DIBN, DIB8 and DIB16 were, respectively: OF (13.8±0.7; 13.5±0.6 and 13.9±0.5mm; P=0.99), OR (90.9%; 83.3% and 75.0%; P=0.93), and IRO (74.4±1.6a; 72.0±0.0ab and 68.0±2.0bh; P=0.02). At Experiment 2, 584 animals were allocated into a 3x2 fatorial design [OI (EC8, EB8.5 and EB9) and FTAI period (FTAI-AM or FTAI-PM)], being treated with DIBN. There was no difference on CR: EC8 (57.5%), EB9 (59.9%) and EB8.5 (49.5%; P=0.09) and IATF AM (56.6%) or PM (54.8%; P=0.66). On Experiment 3, 521 cows were allocated into the same experimental design of Experiment 2, however using DIB8. There was no difference on CR between different OIs: EC8 (47.3%), EB9 (53.3%) and EB8.5 (55.2%; P=0.10). However, there was difference on CR between FTAI-AM (60.7%) and FTAI-AM (48.3%; P=0.01). On Experiment 4, 1192 cows assigned into a 2x3x2 fatorial design (DIBN and DIB8; EB8.5, EB9 and C8; FTAI-AM and FTAI-PM). No differences were found on CR between FTAI-AM (64.6%) or FTAI-PM (59.5%; P=0.06), and OIs; EC8 (65.8%), EB9 (61.8%) and EB8.5 (58.6%; P=0.12). Cows treated with DIBN showed higher CR when compared to those treated with DIB8 (65.8 vs. 59.4%, respectively; P=0.04). These results indicate a similar efficiency using different OIs. Using DIB8, the FTAI-PM showed lower CR. Also the protocol using DIB8 resulted in lower CR than using DIBN.

This dissertation addresses the design of monolithically integrated phase shifters at S- and L- frequency bands using a commercially available GaAs process from Triquint. The focus of the design is to operate over a wide bandwidth with full 360° phase shift capability, 50 Ω input/output impedance match and low RMS phase and gain errors. The first version of the design is based on passive all-pass phase shifters integrated with wideband amplifiers to compensate for insertion loss. This design uses a 4-bit system to achieve the required phase shift and each bit consists of 3 sections of all-pass filters designed at separate frequencies within the 0.8 – 3 GHz band. Simulation results show a complete 360° phase shift with RMS gain error of less than 0.6 dB and RMS phase error of less than 2.5°. The system is also shown to achieve good input and output impedance matching characteristics. However, the fabricated prototype fails to perform with full functionality due to the excessive number of passive inductors in the design and the resulting mutual coupling. The mutual coupling issue could be solved by spacing out the layout to allow more separation among the inductors. Unfortunately, in the S- and L-bands, this is not an option for this research work as the fabricated design already uses the maximum allowed chip size as determined by the foundry. In addition, larger chip sizes considerably increase the cost in practical applications. To address the challenging needs of small size, wide bandwidth and low frequency applicability, the second design introduced in this dissertation proposes a novel phase shifter implementation that utilizes tunable active differential inductors within all-pass networks. The inductor tuning is used to achieve phase shifts up to 180⁰. A switchable active balanced to unbalanced transition circuit (balun) is included in front of the all-pass network to complement its phase shift capability by another 180°. In addition, the all-pass network is followed by a variable gain amplifier (VGA) to correct for gain variations among the phase shifting states and act as an output buffer. Although active inductors have been previously used in the design of various components, to the best of our knowledge, this is the first time that they have been used in an all-pass phase shifter. The approach is demonstrated with an on-chip design and implementation exhibiting wideband performance for S and L band applications by utilizing the 0.5 µm TriQuint pHEMT GaAs MMIC process. Specifically, the presented phase shifter exhibits 1 × 3.95 mm2 die area and operates within the 1.5 GHz to 3 GHz band (i.e. 2:1 bandwidth) with 10 dB gain, less than 1.5 dB RMS gain error and less than 9° RMS phase error. Comparison with the state-of-the-art MMIC phase shifters operating in S and L bands demonstrates that the presented phase shifter exhibits a remarkable bandwidth performance from a very compact footprint with low power consumption. Consequently, it presents an important alternative for implementation of wideband phase shifters where all-passive implementations will consume expensive die real estate.

<p>This thesis deals with the study and comparison of on-chip LC Oscillators, used in energy recovery clocking, in terms of Power, Area of Inductor and change in load capacitance. Simulations show how the frequency of the two oscillators varies when the load capacitance is changed from 5pF to 105pF for a given network resistance. A conventional driver is used as a reference for comparisons of power consumptions of the two oscillators. It has been shown that the efficiency of the two oscillators can exceed that of a conventional driver provided the distribution network resistance is low and the on-chip inductor has a high enough Q value. Conclusions drawn from the simulations, using network resistances varying from 0Ω to 4Ω, show that the selection of the oscillator would depend on the network resistance and the amount of area available for the inductors.</p>

A multilevel Space Vector PWM (SVPWM) technique is developed for a 3-level 3-phase PWM Voltage Source Inverter using a 3-phase coupled inductor to ensure high performance operation. The selection of a suitable PWM switching scheme for the Coupled Inductor Inverter (CII) topology should be based on the dual requirements for a high-quality multilevel PWM output voltage together with the need to minimize high frequency currents and associated losses in the coupled inductor and the inverter switches. Compared to carrier-based multilevel PWM schemes, the space vector techniques provide a wider variety of choices of the available switching states and sequences. The precise identification of pulse placements in the SVPWM method is used to improve the CII performance. The successful operation of the CII topology over the full modulation range relies on selecting switching states where the coupled inductor presents a low winding current ripple and a high effective inductance between the upper and lower switches in each inverter leg. In addition to these requirements, the CII operation is affected by the imbalance inductor common mode dc current. When used efficiently, SVPWM allows for an appropriate balance between the need to properly manage the inductor winding currents and to achieve harmonic performance gains. A number of SVPWM strategies are developed, and suitable switching states are selected for these methods. Employing the interleaved PWM technique by using overlapping switching states, the interleaved Discontinuous SVPWM (DSVPWM) method, compared to other proposed SVPWM methods, doubles the effective switching frequency of the inverter outputs and, as a result, offers superior performance for the CII topology by reducing the inductor losses and switching losses. The inverter operation is examined by means of simulation and experimental testing. The experimental performance comparison is obtained for different PWM switching patterns. The inverter performance is affected by high-frequency inductor current ripple; the excessive inductor losses are reduced by the DSVPWM method. Additional experimental test results are carried out to obtain the inverter performance as a variable frequency drive when operated in steady-state and during transient conditions. The CII topology is shown to have great potential for variable speed drives. / Power Engineering and Power Electronics

Magnetic components, such as inductors and transformers, have important effects on the efficiency and performance of switching power supplies; their parasitic properties directly impact the high frequency properties which can cause lot-to-lot variation or unanticipated and non-ideal operation. They are also amongst the most problematic components to design, often requiring numerous design-prototype-test interactions. The electrostatic and electromagnetic analysis of wound components has become more important recently to predict their performance and frequency behavior. Accurate prediction and design of winding parasitic parameters of leakage inductance and winding capacitance for high frequency inductors and transformers in switching power supplies is fundamental to improve performance, lower cost, and speed time to market. This thesis presents a methodology and process to obtain accurate prediction of the inter- and intra-winding capacitances of high frequency magnetic components. Application examples considered are a single-winding choke, a coupled inductor filter, and a multi-winding transformer. Analytical approach for determination of parasitic capacitances in high frequency magnetic components will be covered also. Comparison of the FEA results using JMAG with experimental and empirical formula results show good agreement, supporting the method as a model-based design tool with the potential to significantly reduce the design-prototype-test cycle commonly needed with sophisticated magnetic designs.

En la tesis, se estudian máquinas eléctricas de flujo axial con rotor conductor sin elementos ferromagnéticos. Se pretende construir un motor de flujo axial, que se alimente con densidades de corriente elevadas para arrastrar un rotor conductor en forma de disco de 30 cm de diámetro. Se estudia el comportamiento térmico de un motor comercial de flujo axial y se comprueba el aumento de potencia que es capaz de suministrar el motor, siempre que se puedan disipar las pérdidas por efecto joule y se eviten daños en los bobinados.Se realiza un trabajo de desarrollo de materiales composites a base de polvo de hierro para evitar las pérdidas en el núcleo de hierro. También se determinan los límites de la densidad de corriente alcanzable al refrigerar directamente por agua.Paralelamente se ensaya un motor comercial trifásico de flujo axial de cuatro pares de polos con rotor de aluminio, para estudiar las conexiones más favorables entre fases que provoquen el mejor desplazamiento del rotor.Se construye un primer prototipo, de cuatro pares de polos, formado por dos semiestátores de doce espiras cada uno (una espira por polo y fase). Se prueba con y sin núcleo ferromagnético. Los conductores son tubo de cobre hueco con una sección importante. Esta segunda parte de la tesis, consiste en la construcción de una serie de prototipos que consiguen la inyección eficaz de fuertes densidades de corriente en el estátor metálico. Se escoge un sistema que trabaja como transformador de intensidad. A partir de un núcleo de transformador y con una relación de transformación adecuada, se generan las corrientes adecuadas para hacer girar el rotor. Son los llamados inductores primarios (alimentación de red) y el inductor secundario (transformación a fuente de corriente, que interacciona directamente con el rotor).Se escogen varias geometrías, máscaras y disposiciones para optimizar la eficacia de los planos activos. Los planos activos son caminos definidos por cortes sobre la pieza de cobre, de formasimilar a las pistas de los circuitos integrados. Se estudia la casuística a temperatura ambiente ya temperatura de nitrógeno líquido. Se construyen 6 prototipos que presentan diferentes estructuras, formas y planos activos entre sí. La finalidad de estos prototipos es la obtención de un campo magnético rotativo credo por las corrientes que circulan por los planos activos.En el tercero de estos prototipos se obtiene un mapa de campo magnético con sonda Hall a diferentes temperaturas (ambiente y temperatura de nitrógeno líquido) para verificar, o no, la obtención de desfases de forma similar a los obtenidos en algunas máquinas con las espiras de sombra. Los mapas de campo magnético permiten obtener el orden de magnitud de las intensidades que pasan por el inductor secundario. Se contrastan estos valores con otros obtenidos mediante espiras exploradoras y registros en osciloscopio.En los prototipos siguientes se realizan conexiones de dos núcleos inductores a la vez que trabajan en monofásico con un desfase de 90º eléctricos entre ellos. Se obtiene un resultado aceptable en el prototipo 7. / This work analyzes electric axial flux motors without ferromagnetic elements and a conductor rotor. We build different prototypes whit a magnetic axial flux and very high currents densities.After different experiments for perform the system, it build a first prototype whit height twelve poles and aluminium rotor. The conductor is a pipe of copper.Then it build the prototypes, whit one only inductor or two inductors, that work in monofasic and with higher currents densities, like a intensity transformer. The rotor has a conductor disc. They are defined the "primary inductors" and "secondary inductor". The secondary inductor is the "active plain". The active plain is a conductor when they are defined different ways for theinduced current by de primary inductor. The purpose of these actives plains is to obtain a rotatory magnetic field.We perform the behaviour at ambient and liquid nitrogen temperature. It obtains the magnetic map in these temperatures and permits to have information about the magnitude of the currents induced in the prototypes. In a prototype with two inductors we have acceptable results.

This thesis deals with the study and comparison of on-chip LC Oscillators, used in energy recovery clocking, in terms of Power, Area of Inductor and change in load capacitance. Simulations show how the frequency of the two oscillators varies when the load capacitance is changed from 5pF to 105pF for a given network resistance. A conventional driver is used as a reference for comparisons of power consumptions of the two oscillators. It has been shown that the efficiency of the two oscillators can exceed that of a conventional driver provided the distribution network resistance is low and the on-chip inductor has a high enough Q value. Conclusions drawn from the simulations, using network resistances varying from 0Ω to 4Ω, show that the selection of the oscillator would depend on the network resistance and the amount of area available for the inductors.

This thesis includes the study of hybrid microwave integrated circuits (HMIC), miniaturization techniques applied on HMICs and its application on a frequency modulated continuous wave (FMCW) range sensor transceiver. In the scope of study, hybrid and monolithic microwave integrated circuits (HMIC and MMIC) are introduced, advantages and disadvantages of these two types are discussed. Large size of HMICs is the main disadvantage especially for military and civil applications requiring miniature volumes. This thesis is mainly devoted on miniaturization work of HMICs in order to cope with this problem. In this scope, miniaturization techniques of some HMICs such as 3 dB hybrid couplers and stubs are examined and analyzed. Their simulation and measurement results cohere with original circuit results. Nevertheless, considerable size reduction up to 80% is achieved. Moreover, planar interdigital capacitors (IDC), spiral inductors (SI) and their equivalent circuit models are introduced. Design technique is discussed with illustrative electromagnetic (EM) simulations. Furthermore, FMCW radar is introduced with its basic operation principles, brief history and usage areas. In addition, FMCW range sensor transceiver is designed with its sub&amp / #8208 / parts / power amplifier, low noise amplifier (LNA), coupler and front end. Multi technology based on chip transistors, interdigital capacitors, spiral inductors and hybrid couplers with wire&amp / #8208 / bond connections is used in the design. As the result of using hybrid miniaturized components small layout size is achieved for the transceiver system with its all components.