Dissertationen zum Thema „Contactless control“
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Gorreta, i. Mariné Sergi. „Dielectric charge control in contactless capacitive MEMS“. Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/460765.
Der volle Inhalt der QuelleLos sistemas micro-electromecánicos, conocidos como MEMS, constituyen una alternativa tecnologíca que ha experimentado un gran crecimiento en las últimas décadas. Desde que en 1959, cuando el físico teórico Richard Feynman introdujo el concepto de nanotecnología en su famosa conferencia "There is plenty of room at the bottom", multitud de investigadores y empresas se han dedicado al desarrollo y la mejora permanente de este tipo de dispositivos. Las principales ventajas del uso de MEMS frente otras tecnologías más clásicas radican en su menor tamaño, su reducido coste y su bajo consumo. En tanto MEMS se refiere habitualmente a tecnologías micrométricaa de dispositivos que presentan partes móbiles, éstos son extensamente utilizados en aplicaciones tanto de detección como de actuación. Así, se ha desarrollado un gran número de microsensores MEMS, cubriendo prácticamente todas las modalidades de detección, incluyendo presión, fuerzas inerciales, sustancias químicas, campos magnéticos, etc. Hoy en día, se utilizan dispositivos MEMS en aplicaciones de mercados como automoción, industria, medicina, telecomunicaciones, defensa, etc. Sin embargo, existen aún problemas de fiabilidad que limitan el uso de los MEMS en determinadas aplicaciones. Los fenómenos mecánicos y eléctricos que se producen en estas estructuras micrométricas han sido objeto de estudio durante los últimos años, siendo el más destacado el producido por la carga eléctrica acumulada en las capas dieléctricas que forman parte de los MEMS actuados electrostáticamente. Esta acumulación de carga altera la distribución de campo eléctrico en el dispositivo, afectando el comportamiento y las prestaciones de éste y causando efectos no deseados, como desplazamientos de la característica Capacidad-Tensión (C-V) e incluso colapsos indeseados de las partes móviles, que pueden conllevar daños permanentes. En consecuencia, la detección y el control de la carga acumulada en dieléctricos de MEMS son temas de vital importancia, debido a su enorme impacto en el rendimiento y la fiabilidad de los dispositivos. Esta Tesis aborda este desafío, primero estudiando y modelizando la dinámica de la acumulación de carga dieléctrica cuando el dispositivo se actúa con tensiones bipolares, y, a continuación, proponiendo y evaluando estrategias de control de dicha carga. Se han demostrado estrategias que, por primera vez, permiten mantener un nivel de carga prefijado en dispositivos MEMS que operan en estado abierto, como varactores, posicionadores electrostáticos o micrófonos MEMS. Además, estos controles han permitido realizar la primera demostración de compensación activa de carga generada por radiaciones ionizantes en dispositivos MEMS. El primer control propuesto consistía en alternar la polaridad de la tensión de actuación, dependiendo del valor de capacidad del dispositivo medido periódicamente. Con el uso de este método se demostró la factibilidad de compensar desplazamientos horizontales de la C-V mediante la inyección de carga debida a la actuación y se abrió el camino para la concepción de un segundo método mejorado. Para la implementación de este segundo método, que fue patentado más tarde, se propusieron dos formas de onda para actuar el dispositivo, que permiten tanto la monitorización como el control de la carga atrapada. Este método se basa en la modulación sigma-delta de primer orden y permite, por primera vez, controlar la carga neta atrapada en el dieléctrico. Finalmente, se han propuesto dos métodos de control más, con el objetivo de introducir mejoras sobre los ya comentados. El primero de ellos implementa una modulación sigma-delta de segundo orden, mientras que en el segundo se introducen algunas modificaciones en el lazo de ralimentación que permiten el control de la capacidad del dispositivo al mismo tiempo que el control de la carga neta atrapada.
Schultz, Aaron M. „Digital control of contactless battery charging system“. Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/37031.
Der volle Inhalt der QuelleIncludes bibliographical references (leaves 230-234).
by Aaron M. Schultz.
Ph.D.
Moghaddami, Masood. „Design Optimization of Inductive Power Transfer Systems for Contactless Electric Vehicle Charging Applications“. FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3853.
Der volle Inhalt der QuelleKong, Cher Rong Matthew. „Contactless liquid flow control for miniaturised analytical techniques on continually rotating centrifugal microfluidic platforms“. Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117150.
Der volle Inhalt der QuelleDans notre société industrielle, la conception de techniques pour la quantification d'espèces chimiques dans l'environnement, les humains et les dérivés de la production manufacturière est primordiale. Au départ, ces techniques avaient été élaborées à partir d'instruments sophistiqués et se basaient sur des procédures complexes. Il serait donc avantageux de pouvoir réduire les coûts d'analyse et simplifier les procédures expérimentales, tout en maintenant un niveau élevé de la qualité des données recueillies. De plus, il est souvent souhaitable de pouvoir effectuer ces mesures rapidement, et si possible sur le site où l'échantillon à analyser est recueilli. Toutes ces caractéristiques bénéfiques des méthodes analytiques peuvent être obtenues, dans certains cas, à travers la miniaturisation. L'intérêt pour la miniaturisation a mené à une croissance rapide des systèmes microfluidiques, un domaine d'études qui se concentre sur l'utilisation de petits volumes de liquide et des systèmes de détection spécialement adaptés à ces volumes réduits. Tout système microfluidique doit intégrer une méthode de transfert des liquides à travers différentes étapes de traitements chimiques ou physiques. Une méthode de pompage particulièrement intéressante utilise la force centrifuge, ce qui permet d'éliminer l'utilisation de pompes ou connections externes au système où s'effectue l'analyse chimique. Jusqu'à présent, les systèmes employant la force centrifuge ont été limités par le nombre d'étapes analytiques consécutives, le liquide ne pouvant se déplacer que dans une seule direction définie par la force centrifuge appliquée.Pour cette thèse, plusieurs techniques de manipulation des liquides sur un système microfluidique à base de force centrifuge ont été dévelopées et caractérisées. Ces techniques ont été utilisées pour miniaturiser les méthodes analytiques classiques pour ensuite les intégrer à des plateformes microfluidiques à base de force centrifuge, l'objectif final étant la surveillance d'espèces chimiques dans l'environnement. Une technique de pompage par déplacement de deux phases liquides et une technique de pompage pneumatique à base de force centrifuge sont démontrées. La technique pneumatique à base de force centrifuge qui a été développée augmente de façon significative les capacités de la boîte à outils des systèmes microfluidiques à base de force centrifuge. Ce nouveau système permet d'effectuer simultanément des opérations essentielles dans les systèmes microfluidiques telles que le transfert de liquides sans valves, les dosages, la commutation du débit des liquides, les micromélanges par agitation ainsi que la recirculation des liquides. Cette technique se base sur l'application sans contact d'une pression pneumatique en utilisant de l'air comprimé sur un système microfluidique à base de force centrifuge en rotation constante. Ceci permet un contrôle complet du débit des liquides en combinant les effets de la pression pneumatique et de la force centrifuge. Le processus de fabrication de ce nouveau système est grandement simplifié par l'ajout du système pneumatique car cela diminue le nombre de valves à intégrer dans le système. De plus, son efficacité est accrue grâce à la possibilité d'effectuer des analyses de façon automatisée. Cette approche pneumatique a été appliquée à des mesures spectrophotométriques par la méthode des additions connues effectuées directement sur le disque. Dans le même ordre d'idées, un autre système employant la fonction pneumatique a été développé pour effectuer des extractions liquide-liquide entre une phase liquide et une phase organique. Ceci a démontré que la plateforme centrifuge est capable non seulement d'effectuer des réactions chimiques complexes en plusieurs étapes, mais aussi de répéter les cycles de réactions et autres processus.
Fabbri, Gabriele. „Control of Five Phase Doubly Fed Induction Machines for Motion and Contactless Power Transmission“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14233/.
Der volle Inhalt der QuelleWestlund, Johan. „Design and construction of a contactless excitation and response measurement system“. Thesis, KTH, Industriell produktion, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-246324.
Der volle Inhalt der QuelleDagens tillverkningsindustri arbetar för att utrsutningens totala effiktivitet ska höjas genomatt öka hastigheten och minska material- och verktygsanvändningen vid bearbetningen utan att minska kvalitén på slutprodukten. För att öka hastigheten krävs en god kännedom om maskinens egenskaper för att maskinen ska arbeta under stabila förhållanden där också verktygets slitage minskas. Att ta fram modeller över maskinen är därför viktigt och inom skärande bearbetning är frekvensresponsmätning ett sätt att få ut de dynamiska egenskaperna av det skärandeverktyget. En vanlig testmetod är att med en hammare exitera verktyget och mäta responsen. Problemet är dock att hammaren bara kan mäta vid stillastående maskin. Vid MMS har en testmetod för kontaktlös exitering tagits fram där elektromagneter användsför exiteringen. På så sätt kan testet utföras på roterande verktyg utan att man behöver förbruka material. I detta arbete har ett nytt testsystem för denna testmetod designats och konstruerats för att testa om det är möjligt med testning på flera storlekar på maskiner för skärandebearbetning. Resultaten för prototypen presenteras och utvärderas.
Krimi, Soufiene [Verfasser]. „Non-Destructive Terahertz Sensor for In-line Contactless Thickness Measurement and Quality Control of Multi-Layered Structures / Soufiene Krimi“. München : Verlag Dr. Hut, 2016. http://d-nb.info/1103872869/34.
Der volle Inhalt der QuelleNěmec, Radek. „Systém pro ovládání počítačové prezentace s využitím gest“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442497.
Der volle Inhalt der QuelleVeron, Baptiste. „Modélisation et commande des systèmes de manipulation sans contact. : Vers l'amélioration du diagnostic en endoscopie digestive“. Thesis, Besançon, 2014. http://www.theses.fr/2014BESA2048/document.
Der volle Inhalt der QuelleDiagnostic techniques currently used in gastrointestinal endoscopy do not allow a completeand accurate observation of the small bowel. Endoscopic capsules were designed to solvethis problem, but the doctor cannot control their movement once they are swallowed bypatients. In that context, the work developed in this thesis focuses on the use of magneticfields to manipulate an object (such as a capsule) without contact, on a large workspace.For this, we study magnetic systems with mobile electromagnets. We study first how tomodel the magnetic field created by an electromagnet. We develop an analytical modeltaking into account the ferromagnetic core of electromagnets. Then, we study a genericsystem composed of n electromagnets which can move throughout space. We develop amodel of the system, integrating the mobility of each of the electromagnets. This modelis then linearized, allowing us to introduce a linearizing control. This command allowsindependent management of the movement of each of the electromagnets, and the currentflowing in it. Finally, the model and the command are tested in simulation and on anexperimental device.Keywords: Magnetism
Archenti, Andreas. „A Computational Framework for Control of Machining System Capability : From Formulation to Implementation“. Doctoral thesis, KTH, Maskin- och processteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48824.
Der volle Inhalt der QuelleQC 20111123
Vidal, Denis Tadeu Rajh. „Elaboração de um sistema de controle externo do fluxo eletrosmótico para eletroforese capilar com detecção condutométrica sem contato“. Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-21072008-151809/.
Der volle Inhalt der QuelleThis work presents the implementation, in an equipment for capillary electrophoresis (CE) with contactless conductivity detection (C4D), of a system for external control of the electroosmotic flow (EOF) via external radial voltage (Vrad). Through external potential, directly applied to the capillary, the electroosmotic flow can be controlled, because this practice couples the applied external potential to the zeta potential through the buffer solution within the capillary. The use of the technique allowed the baseline resolution of two amino acids (Leucine and Isoleucine), whose mobilities differ only by 0,12 cm2.V-1.s-1, using acetic acid 500 mmol.L-1 at pH = 2,55 as the running electrolyte. The approach, called \"infinite capillary column\", consists in successive reversals in the direction of the EOF, trapping species within the capillary column with electrophoretic mobility smaller than the EOF mobility. Thus, the two amino acids were retained by a period of approximately 120 minutes in the capillary that was enough to promote the baseline resolution. Previous works describe that the reversion of the EOF becoming more difficult as pH increases. In order to achieve a more effective control of EOF at high pH values (limiting the technique to a narrow performance band), tests were carried out in electrolytes containing flow reversing agents such as CTAB, CaCI2 and BaCI2. These additives were used at very low concentrations, which kept the normal direction of EOF, and the use of such agents had only the purpuse of reducing the density of silanolate groups in solutions of pH above 6,0. This approach allowed the reversion of the EOF using MES/HIS buffer, which pH was 6,1. Finally, this research has generated an interesting perspective about the possibility of finding combinations of electrolytes and surfactants aiming the Vrad range´s extension at high pH values.
Delettre, Anne. „Conception, modélisation et commande d’une surface de manipulation sans contact à flux d’air induit“. Thesis, Besançon, 2011. http://www.theses.fr/2011BESA2037/document.
Der volle Inhalt der QuelleThis thesis presents the design, the modeling and the control of a pneumatic manipulatorbased on an original aerodynamic traction principle. An horizontal air flow is induced by strongvertical air jets in order to manipulate objects without contact. The objects are maintained inconstant levitation on an air cushion. Three degrees of freedom positioning of the objects canbe realized thanks to the right combination of distributed air jets. The design of an originalmanipulator using this aerodynamic principle is detailed. The device has been integrated in anexperimental setup in order to validate the manipulation principle : objects can reach velocityof 180 mm/s. Several models of the system have been established. A first model, based on experimentaldata, gives the evolution of the 1 DOF-position of an object on the device. Twoother models, based on a fundamental aerodynamic study, respectively give the evolution of the2- and 3-DOF position of the objet. The three models have been validated experimentally. Inorder to control the position of the object, different controllers have been designed : a PID oneand a robust H1 one. The control of one and two degrees of freedom of the device gives goodperformances : settling time of around 2 s and overshoot less than 5% in most of the cases. Wehave also studied a micro-manipulator that is able to position millimetric sized objects, in twodirections, thanks to inclined air jets. Objects can reach velocity of 123 mm/s, and the resolutionof the positioning is less than 0.4 μm
Mejzlík, Jiří. „Návrh jednoúčelového stroje pro měření průhybu“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232101.
Der volle Inhalt der QuelleSarti, Luca. „Analisi e controllo di un convertitore LLC per il trasferimento contactless dell'energia“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Den vollen Inhalt der Quelle findenVoiry, Matthieu. „Étude et conception d'un système automatisé de contrôle d'aspect des pièces optiques basé sur des techniques connexionnistes“. Thesis, Paris Est, 2008. http://www.theses.fr/2008PEST0077/document.
Der volle Inhalt der QuelleIn various industrial fields, the problem of diagnosis is of great interest. For example, the check of surface imperfections on an optical device is necessary to guarantee its operational performances. The conventional control method, based on human expert visual inspection, suffers from limitations, which become critical for some high-performances components. In this context, this thesis deals with the design of an automatic system, able to carry out the diagnosis of appearance flaws. To fulfil the time constraints, the suggested solution uses two sensors working on different scales. We present one of them based on Normarski microscopy, and the image processing methods which allow, starting from issued data, to detect the defects and to determine roughness in a reliable way. The development of an operational prototype, able to check small optical components, validates the proposed techniques. The final diagnosis also requires a classification phase. Indeed, if the permanent defects are detected, many “false” defects (dust, cleaning marks. . . ) are emphasized as well. This complex problem is solved by a MLP Artificial Neural Network using an invariant description of the defects. This representation, resulting from the Fourier-Mellin transform, is a high dimensional vector, what implies some problems linked to the “curse of dimensionality”. In order to limit these harmful effects, various dimensionality reduction techniques (Self Organizing Map, Curvilinear Component Analysis and Curvilinear Distance Analysis) are investigated. On one hand we show that CCA and CDA are more powerful than SOM in terms of projection quality. On the other hand, these methods allow using more simple classifiers with equal performances. Finally, a modular neural network, which exploits local models, is developed. We proposed a new classification problems decomposition scheme, based on the intrinsic dimension concept. The obtained data clusters of homogeneous dimensionality have a physical meaning and permit to reduce significantly the training phase of the classifier, while improving its generalization performances
Liang, Chih-cheng, und 梁志誠. „Contactless Li-Mn Battery Charger with Intelligent Control“. Thesis, 2014. http://ndltd.ncl.edu.tw/handle/74845785019760903496.
Der volle Inhalt der Quelle國立中央大學
電機工程學系在職專班
102
A digital signal processor (DSP)-based TSK-type probabilistic fuzzy neural network with asymmetric membership function (TSKPFNN-AMF) is proposed in this study to control a contactless battery charger. The half-bridge series resonant converter (SRC) is employed in the power stage while the designed charger adopts constant-current and constant-voltage (CC-CV) charging strategy to charge a Li-Mn battery pack. In order to improve the inferior electromagnetic induction and efficiency of the U-shape ferrite core transformer, the U-shape ferrite core transformer is replaced by the circular pad couplers. As a result, the air gap distance of two circular pads can reach 20mm and the efficiency is 80% at the rated output power. Moreover, to improve the transient of voltage regulation during load variation and the tracking of current command change, a TSKPFNN-AMF controller is proposed to replace the traditional proportional-integral (PI) controller. The proposed TSKPFNN-AMF is incorporated into the CC-CV charging strategy in order to overcome the current ripple that comes after the transition from CC to CV charging. The network structure and the online learning algorithms of the TSKPFNN-AMF controller are introduced in detail. Furthermore, the control performances of the proposed TSKPFNN-AMF control system for CC-CV charging are evaluated by some experimental results.
王佩瑛. „The Sensor Control Module Contactless of Instant Electric Water Heater“. Thesis, 2013. http://ndltd.ncl.edu.tw/handle/00207537024064029425.
Der volle Inhalt der Quelle國立彰化師範大學
電機工程學系
101
With the industry development, the application of water heating is progressed from firewood to natural gas and electricity as heating sources. Because of the feature of fast heating and high efficiency, electronic heater is widely utilized in household to improve the living convenience. However, the temperature of tankless water heater cannot be changed with minor adjustment, which has been compensated by digital thermostat water heater in literature. Also, traditional metal contacting, utilized to control the signal of temperature, might cause electric leakage and rusted metal. Therefore, a sensor control module is proposed in this study to avoid above shortages and reach the purpose of contactless control through ultrared ray sensor. The system of sensor control module for instaneous water heater is to control water temperature without touching the water heater. In the system, a microprocessor control unit is utilized to control the relay and then adjust the heating condition of contactless sensor. The experiment applies reflective sensor of ultrared rays to be the temperature controller with an operating frequency between 2 kHz to 5 kHz. The signal is evaluated as effective while the sensing period is more than 30 ms. The result proves the proposed system achieves the function of contactless temperature control and the advantage of maintenance-free to extend product life.
CHE, TSAI WEI, und 蔡維哲. „The Investigation and Implementation in Contactless Programmable PWM Control Systems“. Thesis, 2014. http://ndltd.ncl.edu.tw/handle/14570395803174571533.
Der volle Inhalt der Quelle大葉大學
電機工程學系
102
The goal of this thesis is to develope a kind of contactless way in order to control sustainable energy device power system. The implemented system can match most sustainable energy, such as solar energy or wind power. The system called as PWM(Pulse Width Modulation) control system which can automatically switch to the best way to control sustainable energy power system and fit in some other devices charging with green energy too. Because single chip is highly customized and it also can transfer power instantly to drive device up, like charge a smartphone with a current driver circiut. With the control system, traditional sustainable energy deivces can in work longer lifetime and much stable. Through adjustable wireless protocols, bluetooth, PWM, low-power multi-purpose regulator circuit and instant feedback display, can optimize most sustainable energy devices. The control system is built up by a 8051 single chip microcontroller as the integration of the control core of a circuit, voltage feedback monitor at the same time.
Chang, Chun-Chieh, und 張俊傑. „Contactless Bidirectional Charging and Discharging System Positioning Control for Parking Lot using GMR Sensor“. Thesis, 2015. http://ndltd.ncl.edu.tw/handle/82409268415310760379.
Der volle Inhalt der Quelle國立中興大學
電機工程學系所
103
Implementation of a novel multifunctional contactless sensor based on the giant magneto resistance (GMR) effect combined with a bidirectional charging and discharging system positioning control scheme for parking lot’s vehicles is proposed. Traditional Hall effect sensors detect magnetic flux changes, however, if the changes are not significant enough to induce interference voltage level there will be leading to error judgment. On the other hand, a GMR sensor may detect tiny changes in the magnetic field which will produce a larger change in resistance; this resistance is less susceptible to external noise influence while producing a relatively stable output signal level. As a novel application, our research combines the GMR sensor, a flexible magnetic stripe, a microprocessor and a bidirectional charging and discharging system to fulfill a positioning control system for the parking lot’s vehicles. Real-world experiments are conducted to verify the proposed approach.
Yeh, Chao-Wang, und 葉朝旺. „Contactless Bidirectional Charging and Discharging System Positioning Control for Car Parking Using GMR Sensor“. Thesis, 2015. http://ndltd.ncl.edu.tw/handle/02889845709858791980.
Der volle Inhalt der Quelle國立中興大學
電機工程學系所
104
Implementation of a novel multifunctional contactless sensor based on the giant magneto resistance (GMR) effect combined with a bidirectional charging and discharging system positioning control scheme for parking lot’s vehicles is proposed. Traditional Hall effect sensors detect magnetic flux changes, however, if the changes are not significant enough to induce interference voltage level there will be leading to error judgment. On the other hand, a GMR sensor may detect tiny changes in the magnetic field which will produce a larger change in resistance; this resistance is less susceptible to external noise’s influence while producing a relatively stable output signal level. As a novel application, our research combines the GMR sensor,a flexible magnetic stripe,a microprocessor and a bidirectional charging and discharging system to fulfill a positioning control system for the parking lot’s vehicles.Real-world experiments are conducted to verify the proposed approach.
Chien, Tsung-Shih, und 簡宗石. „Design and Implementation of the Planar Contactless Battery Charging System with Primary Side Current Feedback Control“. Thesis, 2010. http://ndltd.ncl.edu.tw/handle/91381960284316915623.
Der volle Inhalt der Quelle國立彰化師範大學
電機工程學系
98
Contactless power transmission (CPT) has been widely applied in recent year. One common methodology of contactless power transmission control is to add the converter in primary or secondary side of contactless transformer and capitalize the load voltage and current feedback signal to control the converter power switches to adjust the output power with PWM. Nonetheless, this method is less suitable for the occasion where feedback circuit cannot be placed in the secondary side, such as human body, small electronic products, batteries and other equipment. Hence, this study presents a contactless power transmission system with the characteristics of constant current output, in which the output current of secondary side can be controlled by the feedback circuit of primary side to reach the purpose of supplying the load by constant current. The PIC30F6010 is selected as core controller in the system and structured by half bridge inverter with compensation circuit of primary and secondary series compensation. The Pspice circuit simulation software is used for analyzing and verifying the feasibility of circuit. The experimental result shows when resistance is from 20 Ω~30 Ω, the ouput current has better range of linear control. With the proposed method of feedback control in primary side, the result shows 75.9 % of overall efficiency while the air gap is 5mm, the output power is 15.5 W.