Conversor CC-CC tipo T ZVS PWM: análise, projeto e implementação Autor:Bandeira Junior, Delvanei Gomes -Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Elétrica, Florianópolis, 2014 BRASIL.

Conversor CC-CC tipo T ZVS PWM: análise, projeto e implementação Autor: Bandeira Junior, Delvanei Gomes Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Elétrica, Florianópolis, 2014.

 LINK ORIGINAL DA DISSERTAÇÃO DE MESTRADO https://repositorio.ufsc.br/handle/123456789/128980

 LINK DIRECTO ARQUIVO PDF 
https://repositorio.ufsc.br/bitstream/handle/123456789/128980/328199.pdf?sequence=1&isAllowed=y

 Abstract : This work presents the analysis of the T-Type Zero Voltage Switching Pulse Width Modulated isolated DC-DC converter (TT-ZVS-PWM Converter). The topology is composed of four switches. Two of them are subjected to the input voltage level and the other two to half the input voltage. All primary side switches commutate under zero-voltage. The proposed converter has the following in common with the Full Bridge Zero-Voltage Switching (FB-ZVS-PWM) and the Three-Level Zero-Voltage Switching (TL-ZVS-PWM) converters: (a) symmetrical operation of the isolation transformer, (b) modulation by pulse-width with constant frequency, (c) zero voltage switching, and (d) three-level voltage applied to the primary winding of the transformer. Theoreticalanalysis, small signal model, design example and experimental results for a 3 kW, 400 VDC input, 60 VDC output, and 50 kHz switching frequency laboratory prototype, are included. Measured efficiency was 93% at full load and a peak efficiency of 95.2% occured at 1.2 kW.

 RESUMO Este trabalho apresenta o estudo de um conversor CC-CC isolado com comutação suave, saída em corrente, para aplicações envolvendo altas potências, com nome T-Type Zero Voltage Switching Pulse Width Modulated dc-dc converter(TT-ZVS-PWM). O conversor a ser estudado possui quatro interruptores. Dois deles são submetidos à tensão de entrada, já os outros dois são submetidos à metade da tensão de entrada. Todos os interruptores comutam sob tensão nula. O conversor proposto possui as seguintes semelhanças com os conversores Full Bridge Zero Voltage Switching(FB-ZVS-PWM) e Three Level Zero Voltage Switching(TL-ZVS-PWM): (a) Operação simétrica (b) Modulação por largura de pulso com frequência constante (c) comutação sob tensão nula e (d) tensão de saída do conversor com três níveis, a ser aplicada nos terminais do primário do transformador. O trabalho é dividido em análise teórica, análise do modelo de pequenos sinais do conversor e roteiro para projeto do conversor. Um protótipo com 3 kW, 400 V de entrada, 60V de saída e frequência de comutação de 50 kHz comprova a análise desenvolvida. A eficiência obtida no protótipo foi de 93% para carga nominal e de 95,2% para 1,2 kW

Power Transfer Through Strongly Coupled Resonances by André Kurs Master of Science in Physics at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY

Power Transfer Through Strongly Coupled Resonances by André Kurs

Submitted to the Department of Physics in partial fulfillment of the requirements for the degree of Master of Science in Physics at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY September 2007.

 Chapter 1
 Introduction
At the turn of the 20th century, Nikola Tesla [1, 2, 3] devoted much effort to developing a system for transferring large amounts of power over continental distances. His main goal was to bypass the electrical-wire grid, but for a number of technical and financial difficulties, this project was never completed. Moreover, typical embodiments of Tesla's power transfer scheme (e.g., Tesla coils) involve extremely large electric fields and are potential safety hazards. The past decade has witnessed a dramatic surge in the use of autonomous electronic devices (laptops, cell-phones, robots, PDAs, etc) whose batteries need to be constantly recharged. As a consequence, interest in wirelessly recharging or powering such devices has reemerged [4, 5, 6]. Our attempts to help to fulfill this need led us to look for physical phenomena that would enable a source and a device to exchange energy efficiently over mid-range distances, while dissipating relatively little energy in extraneous objects. By mid-range, we mean that the separation between the two objects effecting the transfer should be of the order of a few times the characteristic sizes of the objects. Thus, for example, one source could be used to power or recharge all portable devices within an average-sized room. A natural candidate for wirelessly transferring powering over mid-range or longer distances would be to use electromagnetic radiation. But radiative transfer [7], while perfectly suitable for transferring information, poses a number of difficulties for power transfer applications: the efficiency of power transfer is very low if the radiation is omnidirectional (since the power captured is proportional to the cross-section of the receiving antenna, and most of the power is radiated in other directions), and requires an uninterrupted line of sight and sophisticated tracking mechanisms if radiation is unidirectional (which might also damage anything that interrupts the line of sight). An alternative approach, which we pursue here, is to exploit some near-field interaction between the source and the device, and somehow tune this system so that efficient power transfer is possible. A recent theoretical paper [8] presented a detailed analysis of the feasibility of using resonant objects coupled through their near-fields to achieve mid-range energy transfer. The basic idea is that in systems of coupled resonances (e.g. acoustic, electro-magnetic, magnetic, nuclear), there may be a general strongly coupled regime of operation [9]. It is a general physical property that if one can operate in this regime in a given system, the energy transfer is expected to be very efficient. Mid-range power transfer implemented this way can be nearly omnidirectional and efficient, irrespective of the geometry of the surrounding space, and with low losses into most off-resonant environmental objects [8]. The above considerations apply irrespective of the physical nature of the resonances. In the current work, we focus on one particular physical embodiment: magnetic resonances [10], meaning that the interaction between the objects occurs predominantly through the magnetic fields they generate. Magnetic resonances are particularly suitable for everyday use because biological tissue and most common materials do not interact strongly with magnetic fields, which helps make the system safer and more efficient. We were able to identify the strongly coupled regime in the system of two coupled magnetic resonances by exploring non-radiative (nearfield) magnetic resonant induction at MHz frequencies. At first glance, such power transfer is reminiscent of the usual magnetic induction [11]; however, note that the usual non-resonant induction is very inefficient unless the two coils share a core with high magnetic permeability or are very close to each other. Moreover, operating on resonance is necessary but not sufficient to achieve good efficiency at mid-range distances. Indeed, Tesla's pioneering work made extensive use of resonant induction, and many technologies available today (e.g., radio receivers, RFID tags, and cochlear implants [12]) also rely on resonance, yet their efficiencies are not very good at mid range distances. Operation in the strong-coupling regime, for which resonance is a precondition, is what makes the power transfer efficient.

LINK THESIS
http://www.mediafire.com/download/ctld702cydgxh4c/317879200-MIT.pdf

About Wireless Power Transfer

I talk about magnetically coupled wireless electricity technology. Lots about inductors, Q factor, AC losses and what this all means for practical implementations of wireless power transmission.
 Main article is here: http://www.vk2zay.net/article/253
 Circuit of demo TX/RX here: http://www.vk2zay.net/article.php/262

Circuitos Elétricos - Aula 13 - Redes de 1ª Ordem - Parte 1 - Professor ministrante: Leopoldo R. Yoshioka

Engenharia de Computação Univesp - Circuitos Elétricos Curso de Engenharia de Computação Disciplina EEC-001 - Circuitos Elétricos Univesp - Universidade Virtual do Estado de São Paulo Professor responsável: João Francisco Justo Filho Professor ministrante: Leopoldo R. Yoshioka

INDUCTIVE POWER TRANSFER TECHNOLOGY FOR MOBILE BATTERY CHARGER by SATISH ROUSHAN. Department of Electrical Engineering National Institute of Technology Rourkela- INDIA-2014

INDUCTIVE POWER TRANSFER TECHNOLOGY FOR MOBILE BATTERY CHARGER

 A Thesis presented in partial fulfillment of the exigency for the degree of Bachelor of Technology in “Electrical Engineering” 
By SATISH ROUSHAN
 Under guidance of Prof. SUSOVAN SAMANTA


ABSTRACT
 Inductive power transfer (IPT) is an application of electromagnetic induction principle. Since electromagnetic induction phenomena is directly proportional to the operating frequency, so as we increase the operating frequency, amount of energy transfer from one coil to another coil will also increase. As our power supply frequency is 50Hz so at this frequency, amount of energy transfer from one coil to another coil will be very less. In this thesis it is shown that, to transfer maximum amount of energy from one coil to another coil, it is necessary to use IPT at high frequency. At high frequency skin effect is more pronounced but there is a resonant frequency where overall efficiency is more in spite skin effect. To increase the power factor of IPT circuit compensated capacitor has used. There are four types of compensated topology but to use the IPT circuit in mobile battery charger primary-series-secondary-parallel (P-S-S-P) is more useful.

LINK ORIGINAL EN LA WEB
http://ethesis.nitrkl.ac.in/6417/1/E-85.pdf