Qualificação e etiquetagem de inversores para sistemas fotovoltaicos conectados à rede PARTE II

TESIS QUALIFICAÇAO E ETIQUETAGEM DE INVERSORES PARA SISTEMAS FOTOVOLTAICOS CONETADOS A REDE PARTE-II from armando cavero on Vimeo.

Qualifying and Labeling of Inverters for Grid-Connected Photovoltaic Systems - Qualificação e etiquetagem de inversores para sistemas fotovoltaicos conectados à rede PARTE I

TESIS QUALIFICAÇAO E ETIQUETAGEM DE INVERSORES PARA SISTEMAS FOTOVOLTAICOS CONETADOS A REDE PARTE-I from armando cavero on Vimeo. Dissertação de Mestrado Autor Pinto Neto, Aime Fleury de Carvalho (Catálogo USP)
Nome completo Aime Fleury de Carvalho Pinto Neto
 Unidade da USP Energia Área do Conhecimento Energia Data de Defesa 2012-05-30 Imprenta São Paulo,2012
Orientador Zilles, Roberto (Catálogo USP) Banca examinadora Zilles, Roberto (Presidente) Pinho, João Tavares Rüther, Ricardo
Título em português Qualificação e etiquetagem de inversores para sistemas fotovoltaicos conectados à rede Resumo em português
Este trabalho apresenta o desenvolvimento de uma metodologia para a etiquetagem e qualificação de inversores para Sistemas Fotovoltaicos Conectados à Rede, com finalidade de servir de proposta de procedimento para inclusão no Regulamento de Avaliação de Conformidade de Equipamentos e Sistemas Fotovoltaicos do Programa Brasileiro de Etiquetagem. O procedimento desenvolvido avalia os inversores quanto à eficiência, qualidade de energia, proteções e informações operacionais e de instalação.
ESTA TESIS ESTA DIVIDIDO EM 02 PARTES This work presents the development of a methodology for qualification and labeling of inverters for grid-connected photovoltaic systems, aiming serving as procedural proposal for inclusion in the Conformity Assessment Rules of Equipments and Photovoltaic Systems of the Brazilian Labeling Program. The developed procedure evaluates the inverters efficiency, power quality, protections and operational and installation information.
 LINK THESIS FULL
http://www.teses.usp.br/teses/disponiveis/86/86131/tde-28062012-174659/publico/Dissertacao.pdf

Thevenin's Theorem - by Prof. Dr. C. B. Bangal

具柔性切換單元之脈寬調變轉換器 推演與應用 Development and Application of PWM Converters with Soft-Switching Cells

Development and Application of PWM Converters with
    Soft-Switching Cells

研 究 生：洪金泉    Student:   Jin-Chyuan Hung
指導教授：吳財福 博士    Advisor:   Tsai-Fu Wu, Ph. D.


國立中正大學工學院 電機工程研究所
    博士論文

A Dissertation Submitted to Institute of Electrical Engineering
 College of Engineering National Chung Cheng University
in Partial Fulfillment of the Requirements for the Degree of
Doctor of Philosophy  in Electrical Engineering
    January 2005
Chiayi, Taiwan, Republic of China

ABSTRACT
Due to their simplicity and low steady-state component stress, pulse width modulated
(PWM) converters are broadly used in various power-conversion applications. However, they
have some drawbacks, such as high stress and high loss at switching transition, which will
limit their operation at high frequency. Soft-switching methods are thus used to reduce the
stress and loss.
A family of soft-switching cells (SSCs) for non-isolated and isolated PWM converters is introduced. These cells are derived from the quasi-square-wave converters (QSWCs), in which zero-voltage switching is an inherent feature. A selected SSC and a hard-switching PWM converter are combined by the synthesis process achieving that the PWM converter maintains the power process while the SSC performs the active-clamp function. The PWM converter with the SSC, clamping action and soft-switching feature in both main and auxiliary switches can be achieved. In this dissertation, synthesis process is proposed to unify some of the published soft-switching PWM converters. Based on the proposed synthesis process, families of new converter topologies can be systematically generated.
By introducing SSCs to the conventional single-stage power factor corrector (PFCs), the soft-switching features can be achieved and the energy trapped in the leakage inductor can be also recovered. For reducing input current ripple, two interleaving methods are proposed. Additionally, input power factor and total harmonics distortion of the PFCs with SSCs can be further improved by using an asymmetrical PWM manner.
By introducing SSCs to the coupled-inductor converters and push-pull converters, the
soft-switching features can be achieved and the energy trapped in leakage inductor can be also
recovered. Experimental results have shown that surge voltage can be suppressed effectively.
With the coupled inductors, active switches in the converters can sustain proper duty cycles
while operated with high step-up and/or high step-down voltage ratio, reducing component
stress significantly. Thus, the conversion efficiency of the converters is improved significantly.
In the push-pull converter, SSCs are used to eliminate potential flux imbalance existing in the
conventional push-pull converter which makes the converter more viable. In addition, all of

the proposed converters can be regulated with an asymmetrical PWM control, reducing cost and complexity.
Finally, based on the operational principles, detailed analysis, design procedures,
implementations and discussions of soft-switching PWM converters are presented. The
measured results have verified the feasibility of the discussed soft-switching converters.
LINK
http://www.mediafire.com/view/?lhjl4hr44grhtnj

IMPLEMENTATION OF THREE-PHASE FED DC POWER SUPPLY SYSTEM WITH HIGH POWER FACTOR CHUNG YUAN CHRISTIAN UNIVERSITY

In this thesis, a high efficiency power supply system with high
power factor is proposed for high power applications. The studied power
supply system consists with a three-phase three-switch power factor
corrector (PFC) and a phase-shifted zero-voltage-transition full-bridge
DC/DC converter with current doubler rectification. High power factor
input can be achieved by the adopted PFC circuit with a simple
configuration. The phase-shifted operation of the full-bridge DC/DC
converter provides the zero-voltage-switching (ZVS) features for the
bridge switches to reduce the switching losses effectively. The current doubler rectification reduces significantly the secondary rectification losses. Therefore, high efficiency can be also accomplished. The detailed operating principle and design consideration of this power supply system are analyzed and described. A 1.1kW 55V/20A laboratory prototype was implemented  and  tested.  The  experimental  waveforms  verify  the feasibility of the proposed design. The implemented power supply system exhibits optimum performances such as high power factor, high efficiency, simple configuration and high reliability. 
LINK THESIS
http://www.mediafire.com/view/?sf7319xgbi4q0o9