AUTOR DO BLOG ENG.ARMANDO CAVERO MIRANDA SÃO PAULO BRASIL

"OBRIGADO DEUS PELA VIDA,PELA MINHA FAMILIA,PELO TRABALHO,PELO PÃO DE CADA DIA,PROTEGENOS DO MAL"

"OBRIGADO DEUS PELA VIDA,PELA MINHA FAMILIA,PELO TRABALHO,PELO PÃO DE CADA DIA,PROTEGENOS  DO MAL"

“SE SEUS PROJETOS FOREM PARA UM ANO,SEMEIE O GRÂO.SE FOREM PARA DEZ ANOS,PLANTE UMA ÁRVORE.SE FOREM PARA CEM ANOS,EDUQUE O POVO.”

“Sixty years ago I knew everything; now I know nothing; education is a progressive discovery of our own ignorance. Will Durant”

domingo, 16 de maio de 2021

RETIFICADOR MONOFÁSICO TRÊS NÍVEIS COM ELEVADO FATOR DE POTÊNCIA MODIFICADO PARA APLICAÇÕES EM UPS COM PONTO NEUTRO COMUM ENTRE A CARGA E AS FONTES CA/CC DISSERTAÇÃO DE MESTRADO LEONARDO GÖBEL FERNANDES-

 


RESUMO 

GÖBEL, Leonardo F. Retificador Monofásico Três Níveis com Elevado Fator de Potência Modificado para  Aplicações em UPS com Ponto Neutro Comum Entre a Carga e as Fontes CA/CC. 2019. 197 f. Dissertação – Programa de Pós-graduação em Sistemas de Energia, Universidade Tecnológica Federal do Paraná, Curitiba, 2019.

A dependência de equipamentos eletrônicos é algo cotidiano, e dentro desse contexto existem sistemas cuja operação é considerada crítica, ou seja, não podem falhar devido à falta de energia da fonte de alimentação. A utilização de sistemas com fonte ininterrupta de energia se mostra como uma solução para evitar as perdas monetárias, ou à saúde humana, derivadas destes problemas. Considerando esse cenário é proposto o desenvolvimento e implementação de um retificador/conversor boost, monofásico, meia onda, três níveis com fator de potência unitário. Além disso, a busca por equipamentos com uma compatibilidade eletromagnética elevada fez com que o desenvolvimento desse projeto tivesse como requisito a implementação de um conversor com um ponto neutro comum entre o banco de baterias, rede elétrica e a carga. A análise teórica das etapas de operação, bem como as equações que definem o comportamento do conversor proposto são apresentadas em conjunto com simulações. Os resultados práticos visaram atenderam os principais parâmetros do projeto: tensão de entrada eficaz de 127 V, tensão do banco de baterias de 180 V, potência de saída de até 2,5 kW; que proporcionaram um rendimento superior a 95% para a potência nominal. A utilização de um controlador digital de sinais, modelo MC56F84763 da Freescale Semiconductor®, foi utilizado para garantir a implementação da estratégia de correção do fator de potência, além de possibilitar transitórios de carga e de troca de fontes com estabilização em um curto intervalo de tempo 
LINK:http://repositorio.utfpr.edu.br/jspui/bitstream/1/4703/1/CT_PPGSE_M_Fernandes%2c_Leonardo_Gobel_2019.pdf

domingo, 9 de maio de 2021

Transformerless Single-Phase Universal Active Filter with UPS Features and Reduced Number of Electronic Power Switches W. R. N. Santos, E. M. Fernandes, E. R. C. da Silva, C. B. Jacobina, A. C. Oliveira and P. M. Santos Federal University of Piauí - UFPI Federal University of Campina Grande - UFCG Federal University of Maranhão - UFMA-BRASIL


Transformerless Single-Phase Universal Active Filter with UPS Features and Reduced Number of Electronic Power Switches W. R. N. Santos, E. M. Fernandes, E. R. C. da Silva, C. B. Jacobina, A. C. Oliveira and P. M. Santos Federal University of Piau´ı - UFPI Federal University of Campina Grande - UFCG Federal University of Maranh˜ao - UFMA-BRASIL

 Abstract- This paper presents an universal active power filter for harmonic and reactive power compensation with UPS (Uninterrupted Power Supplies) features. The configurations does not use transformer in the series part. Transformerless modern UPS systems have been rapidly replacing the old technology due to their performance and size attributes. Reducing the numbers of passive elements and/or switches in active power filters and UPS topologies not only reduces the cost of the whole system but also provides some advantages, such as great compactness, smaller weight, and higher reliability. However, the cost reduction requires the use of more complex control strategies. The model of the proposed system is derived and it is observed that the system can be reconfigurable to operate with four or three-leg depending on the issue. A complete control system, including the PWM (Pulse-Width Modulation) techniques, is developed and a comparison between the proposed filter and the standard one is done, as well. Simulated and experimental results validate the theoretical considerations.

Design of an Highly Efficient AC-DC-AC Three-Phase Converter Using SiC for UPS Applications by Wendell C. Alves ,*,Lenin M. F. Morais and Porfirio C. Cortizo


Design of an Highly Efficient AC-DC-AC Three-Phase Converter Using SiC for UPS Applications by Wendell C. Alves ,*,Lenin M. F. Morais  and Porfirio C. Cortizo ,

Graduate Program in Electrical Engineering, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte—MG 31270-901, Brazil Department of Electronic Engineering, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte—MG 31270-901, Brazil

Abstract 

With the constant increase of energy consumption in the world, the efficiency of systems and equipment is becoming more important. Uninterruptible Power Supply (UPS) is an equipment that provides safe and reliable supply for critical load systems, that is, systems where a supply interruption can lead to economical or even human losses. The Double Conversion UPS is the most complete UPS class in terms of load protection, regulation, performance, and reliability, however, it has lower efficiency and higher cost because of its high number of power converters. Silicon Carbide devices are emerging as an opportunity to construct power converters with higher efficiency and higher power density. The main purpose of this work is to design a three-phase AC-DC-AC converter using Silicon Carbide for Double Conversion UPS applications. The aim is to maximize efficiency and minimize volume and mass. The methodologies to size and choose the main hardware components are described in detail. Experimental results obtained with the prototype prove the high efficiency and high power density achievable with Silicon Carbide Metal Oxide Semiconductor Field Effect Transistor (MOSFETs).

LINK: https://www.mdpi.com/2079-9292/7/12/425/htm

On the Practical Design of a High Power Density SiC Single- Phase Uninterrupted Power Supply (UPS) System Cai Chen1, Yu Chen, member, IEEE, Yifan Tan, Jianming Fang1, Fang Luo, senior member, IEEE and Yong Kang1


 On the Practical Design of a High Power Density SiC Single- Phase Uninterrupted Power Supply (UPS) System Cai Chen1, Yu Chen, member, IEEE, Yifan Tan, Jianming Fang, Fang Luo, senior member, IEEE and Yong Kang

Abstract- this paper proposes a high power density SiC singlephase system potential for Uninterrupted Power Supply (UPS) applications. To get the high power density, the semiconductors, packaging, circuit topology and thermal design are synthetically considered. To increase the switching frequency and reduce the size of the passive components, the SiC MOSFETs and diodes are chosen; to minimize the parasitic inductances and eliminate the snubbers, the SiC bare dies are packaged as the Half-Bridge (HB) modules; to remove the bulky DC-link capacitors, the Full-Bridge inverter and the Active Power Filter (APF) are designed, and they are structured by using the fabricated SiC HB modules; and finally to dissipate the heat from such a compact enclosure in the cost-efficient way, the heat-sink of the modules and the forced air cool system are well designed, and the thermal 3D-Finite Element Analysis model is built to survey the best cooling configuration. A 2kVA prototype is built and tested, and the power density of the system is up to 58W/in3 and the maximal efficiency is up to 98.3%.
 LINK:

A High-Performance Online Uninterruptible Power Supply (UPS) System Based on Multitask Decomposition Qiongbin Lin, Member, IEEE, Fenghuang Cai, Wu Wang, Sixiong Chen, Zhe Zhang, Senior Member, IEEE, Shi You, Member, IEEE

 

A High-Performance Online Uninterruptible Power Supply (UPS) System Based on Multitask Decomposition Qiongbin Lin, Member, IEEE, Fenghuang Cai, Wu Wang, Sixiong Chen, Zhe Zhang, Senior Member, IEEE, Shi You, Member, IEEE
Abstract—High quality online uninterruptible power supplies (UPS) are widely used in applications e.g. precision medical equipment with critical loads. This paper proposes a low-cost and high performance online UPS system. Firstly, the performance improvement of a bidirectional switch based bridgeless power factor (PFC) converter, which is regulated by a hybrid control strategy with load current feedforward is studied. Secondly, the proposed closed-loop controller integrates improved predictive current control with predictive voltage control and applies to the second-stage neutral-point-clamped (NPC) three-level inverter for low output voltage harmonics. Moreover, a push-pull dc-dc converter interfaces and boosts voltage of a 24V battery bank as the backup energy source. Considering complexity of the UPS system as well as cost reduction, we implement a multi-task decomposition method for control on a monolithic low-cost digital signal processor (DSP) embedded with Control Law Accelerator (CLA). Finally, the experimental results from a 1kVA a prototype can effectively verify validly of the theoretical analysis and design.