Dissertations / Theses on the topic 'High frequency transformers'
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Shen, Wei. "Design of High-density Transformers for High-frequency High-power Converters." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/28280.
Full textPh. D.
Imdad, Kashif. "High frequency modeling of power transformers under transients." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/457774.
Full textEsta tesis presenta los resultados relacionados con el modelado en alta frecuencia de transformadores de potencia. Primero, un transformador de distribución de 25 kVA es ensayado a perturbaciones tipo rayo y se propone un modelo de alta frecuencia. El método de la función de transferencia es utilizado para estimar sus parámetros. En segundo lugar, se introduce un modelo avanzado de alta frecuencia. El modelo resulta de la investigación y modificación de los modelos de resonancia dual introducido por Sabiha y el de resonancia única introducido por Piantini con condiciones sin carga. El modelo propuesto es capaz de representar tanto la resonancia única como dual. El modelo es validado a partir de los resultados de referencia de Sabiha y Piantini. Los resultados de simulación indican que el modelo representa las sobretensiones transferidas al secundario, las impedancias de transferencia y el trabajo en carga del transformados coinciden con los modelos anteriores tanto en el dominio temporal y de la frecuencia. Los objetivos obtenidos en esta tesis son: * Metodología para determinar los parámetros de un transformador de potencia. * Modelo de alta frecuencia para simular el comportamiento transitorio frente a perturbaciones. * Modificación del modelo de alta frecuencia para representar una y dos resonancias. La originalidad y metodología de la tesis son: * El modelo de alta frecuencia del transformador ha sido obtenido a partir de la metodología de la función de transferencia. En la literatura, esta metodología ha sido usada en muchas aplicaciones como en la determinación de deformaciones mecánicas o fallo de aislamiento en espiras de transformadores. En esta tesis, los parámetros del modelo propuesto son obtenidos mediante esta metodología. * Modificación del modelo de alta frecuencia con resonancia única o dual utilizando el método de la función de transferencia. La metodología propuesta puede ser utilizada para determinar el estado del transformador. Sabiha propuso un modelo de alta frecuencia representado dos resonancias en condiciones de carga y de vacío. Este modelo ha sido utilizado como referencia para la modificación y mejora. En la tesis, el transformador de distribución 25 kVA disponible en el Departamento de Ingeniería Eléctrica de la UPC en la ESEIAAT ha sido ensayado a impulsos tipo rayo. Un algoritmo ha sido desarrollado para estimar los parámetros del transformador mediante el método de la función de transferencia utilizando la transformada de Fourier. En este esquema, una red de dos puertos ha sido adoptada para el análisis del transformador. Los parámetros del transformador como la Z11, Z12., Z21 y Z22 son calculadas para representar las frecuencias consideradas. Mediante el método de la función de transferencia los parámetros del transformador son determinados. El modelo propuesto se basa en elementos simples RLC capaces de representar con precisión dos frecuencias de resonancia. En la segunda parte de la tesis, un nuevo modelo es introducido capaz de representar ambos modelos de resonancia única y dual en uno solo. Se analiza el caso de carga y vacío.
Augla, Kader Hmood. "Losses in high frequency power inductors and transformers." Thesis, University of Bath, 1985. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354726.
Full textWater, Wayne. "Modelling and Design of Advanced High Frequency Transformers." Thesis, Griffith University, 2014. http://hdl.handle.net/10072/367584.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
Full Text
Xue, Jing. "Single-phase vs. Three-phase High Power High Frequency Transformers." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/32919.
Full textMaster of Science
Abou-Fakher, Yehia. "Implementing and simulating low frequency inverters using high frequency transformers and devices." Thesis, University of Bath, 1997. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362147.
Full textBjerkan, Eilert. "High frequency modeling of power transformers : Stresses and Diagnostics." Doctoral thesis, Norwegian University of Science and Technology, Department of Electrical Power Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-622.
Full textIn this thesis a reliable, versatile and rigorous method for high frequency power transformer modeling is searched and established. The purpose is to apply this model to sensitivity analysis of FRA (Frequency Response Analysis) which is a quite new diagnostic method for assessing the mechanical integrity of power transformer windings on-site. The method should be versatile in terms of being able to estimate internal and external overvoltages and resonances. Another important aspect is that the method chosen is suitable for real transformer geometries. In order to verify the suitability of the model for real transformers, a specific test-object is used. This is a 20MVA transformer, and details are given in chapter 1.4.
The high frequency power transformer model is established from geometrical and constructional information from the manufacturer, together with available material characteristics. All circuit parameters in the lumped circuit representation is calculated based on these data. No empirical modifications need to be performed. Comparison shows capability of reasonable accuracy in the range from 10 kHz to 1 MHz utilizing a disc-to-disc representation. A compromise between accuracy of model due to discretisation and complexity of the model in a turn-to-turn representation is inevitable.
The importance of the iron core is emphasized through a comparison of representations with/without the core included. Frequency-dependent phenomena are accurately represented using an isotropic equivalent for windings and core, even with a coarse mesh for the FEM-model. This is achieved through a frequency-dependent complex permeability representation of the materials. This permeability is deduced from an analytical solution of the frequency-dependent magnetic field inside the conductors and the core.
The importance of dielectric losses in a transformer model is also assessed. Since published data on the high frequency properties of pressboard are limited, some initial measurements are done on impregnated pressboard at different temperatures and moisture-levels. Tanδ is found to be twice the corresponding value for impregnated paper at frequencies from 50 kHz to 1MHz. Moisture has a minor effect on the losses when frequency approaches 1MHz. Service-aged paper (impregnated) is also tested in order to investigate other ageing-effects than produced water, but the test show the same decreasing influence at higher frequencies as impregnated pressboard with moisture added. The following main conclusions were drawn from this work:
• A simple, analytical approach cannot be used to build a versatile high frequency power transformer model. The reason being mainly the lack of a proper representation of the iron core, since a FEM-representation without the core did not increase coherence to measurements significantly.
• A proper representation of the iron core is very important for the calculation of inductances. Losses mainly originate from the core at intermediate frequencies (10-200 kHz), and not only from eddy currents in the windings as traditionally assumed. The permeability seem to be of less importance as long as it is well above permeability for oil, since the internal resonances mainly depends on the leakage inductances. The core leg equivalent is important for the leakage field and determines the leakage inductances and winding losses.
• Using a frequency-dependent complex permeability in a FEM-simulation makes possible an accurate representation of core and windings using a coarse mesh. If coating resistivity is sufficiently low to create interlaminar currents/ losses, the iron laminates should be represented by a 2-dimensional complex permeability. Coating parameters are seldom available.
• Dielectric properties of power transformer insulating materials depend on frequency, temperature, moisture, ageing and pressure. Temperature has minor influence on FRA-signatures, other parameters have practically no influence.
• Impulse- and resonant overvoltages both internally and on terminals can be analysed using this method with sufficient accuracy, provided the discretisation of the winding is sufficiently refined regarding the frequencies involved. Since terminal behaviour is given by the internal geometry and material parameters, it is assumed that internal behaviour is related to the accuracy of the terminal behaviour.
• FRA sensitivity to axial displacement is 1.2% of total axial height. The sensitivity to radial deformation (forced buckling) is found to be a buckling depth of 9% of the radius of the winding. Turn-to-turn short-circuits could not be modeled correctly since the lumped elements includes several turns. Disc-todisc short circuits are easily detected. Axial bending is not detectable. Detection of loose windings and aged insulation is improbable and will be dependent on the available sensitivity (mainly related to the repeatability of the measurements and the reference utilized for comparison).
The contributions in this work relates to different topics such as; Frequency-dependent iron core representation in FEM, study of interlaminar currents and its effect on the internal magnetic field, characterization of high frequency dielectric properties of impregnated pressboard and service-aged impregnated paper, procedure for evaluation of internal/external overvoltages, and finally sensitivity guidelines for the application of FRA to mechanical deformations.
Bolborici, Valentin. "Design of low-profile transformers for high-frequency operation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0006/MQ45982.pdf.
Full textJessee, J. Patrick. "A coupled thermal-magnetic finite element model for high frequency transformers." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-12172008-063409/.
Full textWilliams, Richard. "High frequency multi-element transformers for switched-mode power supplies." Thesis, University of Bristol, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283625.
Full textWong, Fu Keung, and n/a. "High Frequency Transformer for Switching Mode Power Supplies." Griffith University. School of Microelectronic Engineering, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050211.110915.
Full textWong, Fu Keung. "High Frequency Transformer for Switching Mode Power Supplies." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367650.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Microelectronic Engineering
Full Text
Dai, Ning. "Modeling, analysis, and design of high-frequency high-density low-profile power transformers." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-06062008-151512/.
Full textZhang, Ziwei. "High frequency finite element modeling and condition assessment of power transformers." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2052862/.
Full textSkutt, Glenn R. "High-Frequency Dimensional Effects in Ferrite-Core Magnetic Devices." Diss., Virginia Tech, 1996. http://hdl.handle.net/10919/30596.
Full textPh. D.
Ambatipudi, Radhika. "High Frequency (MHz) Planar Transformers for Next Generation Switch Mode Power Supplies." Doctoral thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-20270.
Full textLesser, Beverly Brown. "Thermal-magnetic finite element model of a high frequency transformer." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44121.
Full textIn high-frequency power transformers, magnetic material properties cannot be assumed to be constant. These properties vary with frequency, temperature, and magnetic flux density. Heat generation is, in turn, a function of the magnetic permeability, magnetic flux density, and frequency. Current design methods are either empirical or based on linear, uncoupled models. To better understand the relationship between heat transfer, magnetic flux density, material properties, and core geometry in a miniature, high-frequency transformer, a finite-element program has been developed to solve the coupled thermal-magnetic equations for an axisymmetric transformer. The program accounts for nonlinear temperature and magnetic field dependent material properties, geometry, and driving frequency.
The program, HT-MAG, is based on a series of derived magnetic field equations. The Ritz method is applied to the magnetic and thermal equations in the development of the program. The program alternately solves the finite element approximations to the thermal and magnetic governing equations until the magnetic properties match within a specified fraction or a maximum number of iterations are performed. In addition, the program can be linked with existing pre- and post-processors or can accept manual pre- and post-processing.
Six test cases were run to test the validity of the program. The first two cases tested the uncoupled heat transfer calculations. One of these tested the thermal conduction calculations while the other tested the heat generation calculations. The next two cases tested the uncoupled magnetic equations. The first was a direct current (DC) case, while the second was an alternating current (AC) case. The final two cases tested the thermal magnetic coupling. Solutions to these cases are presented and discussed.
Master of Science
Murthy, Bellur Dakshina S. "Hard-Switching and Soft-Switching Two-Switch Flyback PWM DC-DC Converters and Winding Loss due to Harmonics in High-Frequency Transformers." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1278704361.
Full textAmbatipudi, Radhika. "Multilayered Coreless Printed Circuit Board (PCB) Step-down Transformers for High Frequency Switch Mode Power Supplies (SMPS)." Licentiate thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-13967.
Full textWhitman, Daniel J. "The Effect of Winding Curvature and Core Permeability on the Power Losses and Leakage Inductance of High-Frequency Transformers." Wright State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright1624286375555269.
Full textGradzki, Pawel Miroslaw. "Core loss characterization and design optimization of high-frequency power ferrite devices in power electronics applications." Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-165934/.
Full textKotte, Hari Babu. "High Speed (MHz) Switch Mode Power Supplies (SMPS) using Coreless PCB Transformer Technology." Licentiate thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-13964.
Full textGoksu, Omer. "Shaft Transducerless Vector Control Of The Interior Permanent Magnet Motor With Speed And Position Estimation Using High Frequency Signal Injection And Flux Observer Methods." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609617/index.pdf.
Full textJansson, Vincent, David Bergman, and Niklas Hermansson. "High Frequency Transformer : Implementation of prototype." Thesis, Uppsala universitet, Elektricitetslära, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387307.
Full textAl-Alawi, Hamed. "High frequency modeling of a transformer winding." Thesis, Al-Alawi, Hamed (2012) High frequency modeling of a transformer winding. Other thesis, Murdoch University, 2012. https://researchrepository.murdoch.edu.au/id/eprint/13092/.
Full textLi, Jeffrey. "Integrated High Frequency Transformer Design Virtual Laboratory." Thesis, Griffith University, 2015. http://hdl.handle.net/10072/380060.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
Full Text
Li, Jie. "High frequency power transformer modelling for frequency response analysis (FRA) diagnosis." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538489.
Full textLI, QUAN, and q. li@cqu edu au. "HIGH FREQUENCY TRANSFORMER LINKED CONVERTERS FOR PHOTOVOLTAIC APPLICATIONS." Central Queensland University. N/A, 2006. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20060830.110106.
Full textTavakoli, Hanif. "A High Frequency Transformer Winding Model for FRA Applications." Licentiate thesis, Stockholm : Skolan för elektro- och systemteknik, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11178.
Full textNg, Wing Lun. "Low-voltage high-frequency CMOS transformer-feedback voltage-controlled oscillators /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?ECED%202006%20NG.
Full textMuhammed, Adil Hussein. "High frequency transformer design and modelling using finite element technique." Thesis, University of Newcastle Upon Tyne, 2000. http://hdl.handle.net/10443/747.
Full textSagaale, Mohamoud. "High frequency modelling of a transformer winding for partial discharge localization." Thesis, Sagaale, Mohamoud (2013) High frequency modelling of a transformer winding for partial discharge localization. Other thesis, Murdoch University, 2013. https://researchrepository.murdoch.edu.au/id/eprint/22265/.
Full textTavakoli, Hanif. "An FRA Transformer Model with Application on Time Domain Reflectometry." Doctoral thesis, KTH, Elektroteknisk teori och konstruktion, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48568.
Full textQC 20111122
Kotte, Hari Babu. "High Frequency (MHz) Resonant Converters using GaN HEMTs and Novel Planar Transformer Technology." Doctoral thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-20894.
Full textHigh Frequency Switch Mode Power Supplies
Zhao, Sen Peng. "Design and implementation of a frequency response test system for instrument voltage transformer performance studies." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/design-and-implementation-of-a-frequency-response-test-system-for-instrument-voltage-transformer-performance-studies(3e65a4d8-937e-4a3d-8308-734e03f29255).html.
Full textIuravin, Egor. "Transformer Design For Dual Active Bridge Converter." Miami University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=miami1532601248778308.
Full textKaramat, Asghar. "High frequency inverter-transformer-cycloconverter system for DC to AC (3-phase) power conversion." Thesis, Brunel University, 1991. http://bura.brunel.ac.uk/handle/2438/5195.
Full textSterk, Douglas Richard. "Compact Isolated High Frequency DC/DC Converters Using Self-Driven Synchronous Rectification." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9648.
Full textMaster of Science
Yan, Ning. "High-frequency Current-transformer Based Auxiliary Power Supply for SiC-based Medium Voltage Converter Systems." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/101507.
Full textM.S.
Recently, 10 kV silicon carbide (SiC) MOSFET receives strong attention for medium voltage applications. Asit can switch at very high speed, e.g. > 50 V/ns, the converter system can operate at higher switching frequency condition with very small switching losses compared to silicon (Si) IGBT [8]. However, the fast dv/dt noise also creates the common mode current via coupling capacitors distributed inside the converter system, thereby introducing lots of electromagnetic interference (EMI) issues. Such issues typically occur within the gate driver power supplies due to the high dv/dt noises across the input and output of the supply. Therefore, the ultra-small coupling capacitor (<5 pF) of a gate driver power supply is strongly desired.[37] To satisfy the APS demands for high power modular converter system, a solution is proposed in this thesis. This work investigates the design of 1 MHz isolated APS using gallium nitride (GaN) devices with medium voltage insulation reinforcement. By increasing switching frequency, the overall converter size could be reduced dramatically. To achieve a low Ccm value and medium voltage insulation of the system, a current-based transformer with a single turn on the sending side is designed. By adopting LCCL-LC resonant topology, a current source is formed as the output of sending side circuity, so it can drive multiple loads importantly with a maximum of 120 W. At the same time, ZVS can use realized with different load conditions. The receiving side is a regulated stage, so the output voltage can be easily adjusted and it can operate in a load fault condition. Different insulation solutions will be introduced and their effect on Ccm will be discussed. To further reduce Ccm, shielding will be introduced. Overall, this proposed APS can achieve a breakdown voltage of over 20 kV and PDIV up to 16.6 kV with Ccm<5 pF. Besides, multi-load driving ability is able to achieve with a maximum of 120 W. ZVS can be realized. In the end, the experiment results will be provided.
Ammanambakkam, Nagarajan Dhivya. "Design of HF Forward Transformer Including Harmonic Eddy Current Losses." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1292874300.
Full textZhao, Shishuo. "High Frequency Isolated Power Conversion from Medium Voltage AC to Low Voltage DC." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/74969.
Full textMaster of Science
Li, Quan, and q. li@cqu edu au. "DEVELOPMENT OF HIGH FREQUENCY POWER CONVERSION TECHNOLOGIES FOR GRID INTERACTIVE PV SYSTEMS." Central Queensland University. School of Advanced Technologies & Processes, 2002. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20020807.152750.
Full textHashimoto, Kazuki. "Analysis and Design of Air-Core Transformer Based on Internal Magnetic Flux Density Distribution for High-Frequency Power Converter." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263662.
Full textAhmed, Mohamed Hassan Abouelella. "Power Architectures and Design for Next Generation Microprocessors." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/103175.
Full textDoctor of Philosophy
With the rapid increase of cloud computing and the high demand for digital content, it is estimated that the power consumption of the IT industry will reach 10 % of the total electric power in the USA by 2020. Multi-core processors (CPUs) and graphics processing units (GPUs) are the key elements in fulfilling all of the digital content requirements but come with a price of more power-hungry processors, driving the power per server rack to 20 KW levels. The need for more efficient power management solutions on the architecture level, down to the converter level, is inevitable. The data center manufacturers have recently adopted a more efficient architecture that supplies a 48V DC server rack distribution instead of a 12V DC distribution to the server motherboard. This helped reduce costs and losses, but as a consequence, raised a challenge in the design of the DC/DC voltage regulator modules (VRM) supplied by the 48V, in order to power the CPU and GPU. In this work, different architectures will be explored for the 48V VRM, and the trade-off between them will be evaluated. The main target is to design the VRM with very high-efficiency and high-power density to reduce the cost and size of the CPU/GPU motherboards. First, a two-stage power conversion structure will be used. The benefit of this structure is that it relies on existing technology using the 12V VRM for powering the CPU. The only modification required is the addition of another converter to step the 48V to the 12V level. This architecture can be easily adopted by industry, with only small modifications required on the system design level. Secondly, a single-stage power conversion structure is proposed that achieves higher efficiency and power density compared to the two-stage approach; however, the structure is very challenging to design and to meet all requirements by the CPU/GPU applications. All of these challenges will be addressed and solved in this work. The proposed architectures will be designed using an optimized magnetic structure. These structures achieve very high efficiency and power density in their designed architectures, compared to state-of-art solutions. In addition, they can be easily manufactured using automated manufacturing processes.
Capellán, Villacián Cándido. "Aportaciones al modelado del transformador en AF." Doctoral thesis, Universidad de Cantabria, 2012. http://hdl.handle.net/10803/81555.
Full textModelling is a useful technique able to provide a suitable knowledge about the behaviour of all the devices operated at high frequencies. This thesis approaches this topic to the case of the transformer. A state of the art about high-frequency modelling is summarized and the most relevant research works are analysed. By using a 4 kVA three-phase power transformer, a set-up facility and the associated methodology has been proposed in order to develop a method able to obtain both the low and high-frequency models. The obtained model can be synthesized using passive LCR circuits. The accuracy of the model is then evaluated using the set-up facility. In initial experiments, the classic low-frequency model is put to the test in order know the maximum frequency at which the model can be used. After that, a new high-frequency model is proposed and its response is evaluated and validated with measurements.
Danekar, Abhishek V. "Analysis and Design of High-Frequency Soft-Switching DC-DC Converter for Wireless Power Charging Applications." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1493990400812363.
Full textFei, Chao. "Optimization of LLC Resonant Converters: State-trajectory Control and PCB based Magnetics." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/83206.
Full textPh. D.
Barbosa, Giancarlos Costa. "Projeto de um Transformador utilizado em uma Planta de Plasma." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15453.
Full textCoordena??o de Aperfei?oamento de Pessoal de N?vel Superior
This work discusses the design of a transformer used in a plant plasma. This plant, which is being developed in UFRN, will be used in the treatment of waste. It consists basically of a radio frequency power supply and a inductive plasma torch. The transformer operates at the nominal frequency of 400 kHz, with 50 kW, allowing the adaptation of impedance between the power supply and torch. To develop the project, a study was done on the fabrication technologies and physical effects on the frequency of operation. This was followed by the modeling of this transformer. Finally, simulations and tests were conducted to validate the design
Este trabalho aborda o projeto de um transformador utilizado em uma planta de plasma. Esta planta, que est? sendo desenvolvida na UFRN, ser? utilizada no tratamento de res?duos. Ela ? composta, basicamente, por uma fonte de alimenta??o de radiofrequ?ncia e uma tocha indutiva de plasma. O transformador opera na frequ?ncia nominal de 400 kHz, com pot?ncia de 50 kW, permitindo a adapta??o de imped?ncias entre a fonte de alimenta??o e a tocha. Para o desenvolvimento do projeto, foi feito um estudo sobre as tecnologias de fabrica??o e efeitos f?sicos na frequ?ncia de opera??o. Posteriormente, foi realizada a modelagem deste transformador. Por fim, foram realizados simula??es e testes de forma a validar o projeto
Bacega, Felippe. "Avaliação do estado dos equipamentos do sistema de transporte de energia elétrica através de técnicas de medição de descargas parciais em campo." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/106/106131/tde-05112014-150019/.
Full textThis work presents a new method of measuring partial discharges, through high frequency current transformers, installed in the equipment grounding conductor of the electrical power system and coupled to an oscilloscope. This new measurement method has as great gain, the fact that the equipment doesnt need to be removed from service to perform measurement. Because of the transmission being remunerated by the availability of the transmission functions, diagnosis of equipment in service makes the costs been reduced. A theoretical survey where the characteristic curve expected response from the current transformer to an impulsive signal was set has been done. Characteristic curves were raised in the laboratory through oscillograms in the time domain, of signatures of partial discharges in equipment with SF6 gas and oil isolation, in order to validate expected signal discharges in the theoretical foundation. These signatures were used in field measurements, which proved the feasibility of the theoretical foundation and signatures obtained in the laboratory. Further factors were raised that may influence the measurements and shown signs that have different characteristics from those of partial discharges in order to differentiate them.
Amrhein, Andrew Aloysius. "Induction Heating of Aluminum Cookware." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/77400.
Full textMaster of Science