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”

segunda-feira, 29 de dezembro de 2014

Design of an LCL-Filter for the Three-Parallel Operation of a Power Converter in Wind Turbines DONG-KEUN YOON AJOU UNIVERSITY






Permanent Magnet Synchronous Generators (PMSG) are widely used in variable-speed wind turbines. However, the power devices must support high currents to get their high-power rating because the PMSG is connected directly to the grid through a back-to-back converter. Therefore, the rated current of the power device can be reduced to one third of the rated value by using a three-parallel operation. The low switching frequency of a high power system may cause an increase in the harmonics found in the output current.
This paper proposes a design scheme for an LCL-filter used for three-parallel operation of a power converter in 2MW-wind turbines. An appropriate design method of the delta configured LCL-filter is also proposed to improve the output power quality in the system. A novel design method for the inner inductance of the LCL-filter is proposed in order to overcome the existing trial and error methods used in designing the filter. LCL-filters typically have a problem with a reduced power factor (PF), due to the capacitor used. To improve the poor PF, a simple compensation method is also proposed. The simulation and experimental results demonstrate that the grid current harmonics are low and the PF is improved.

Research on High Efficiency Non-Isolated Push-Pull Converters with Continuous Current in Solar-Battery Systems Yan Li, Trillion Q. Zheng, and Qian Chen


Research on High Efficiency Non-Isolated Push-Pull Converters with Continuous Current in Solar-Battery SystemsYan Li, Trillion Q. Zheng, and Qian Chen
Abstract
 In order to improve the output efficiency of solar cells and to extend the life span of batteries, the input currents of converters are required to be continuous. If low output voltage ripple is required at the same time, it is obvious that the application of basic two-order converters (such as Buck and Boost derived converters) will not be good enough. In this paper, a lot of non-isolated push-pull converters (NIPPCs) with continuous current will be introduced due to their lower current stress, higher efficiency and better EMC performance. By decomposing the converters into push-pull cells, inductor and free-wheeling diodes, two families of NIPPCs based on single inductor and coupled inductor separately are systematically generated. Furthermore, characteristics analyses for some of the generated converters are also shown in this paper. Finally, two prototypes based on the corresponding typical topologies are built in the lab to verify the theoretical outcomes.
LINK
http://jpe.or.kr/archives/view_articles.asp?seq=852

A Novel Circuit Configuration of UPS with Auxiliary Inverter and Its Specific Control Implementations Katsuya Hirachi and Mutsuo Nakaoka





A Novel Circuit Configuration of UPS with Auxiliary Inverter and Its Specific Control Implementations
Katsuya Hirachi and Mutsuo Nakaoka
RESEARCH AND DEVELOPMENT DIVISION POWER SUPPLY  COMPANY,YUASA,OSAKA JAPAN.
DEPT. OF ELECTRICAL AND ELECTRONICS ENGINEERING  YAMAGUCHI UNIVERSITY
YAMAGUCHI JAPAN

Abstract
 The rapid expansion of small computers over the last 10-odd years has brought about great changes in the circumstances affecting UPSs. There are strong demands that UPSs become much smaller and lighter, and more economical, which has resulted in the wide application of the circuit topology without transformer. A disadvantage of such UPS topology is that the DC link voltage is very high, which invites decreased reliability and increased cost of battery bank. Some circuit configurations were proposed to eliminate this disadvantage, but they still had problems. In this paper, a novel circuit configuration which eliminates these problems is proposed and evaluated by the experimental results of prototype UPS.
LINK
http://jpe.or.kr/archives/view_articles.asp?seq=79
LINK DIRECT
http://manuscript.jpe.or.kr/ltkPSWeb/pub/pubfpfile.aspx?ppseq=79

A Three-Phase High Frequency Semi-Controlled Battery Charging Power Converter for Plug-In Hybrid Electric Vehicles Mahmoud M. Amin and Osama A. Mohammed†




Dept. of Electrical and Computer Eng., Florida International University, Florida, United States

Abstract

 This paper presents a novel analysis, design, and implementation of a battery charging three-phase high frequency semicontrolled power converter feasible for plug-in hybrid electric vehicles. The main advantages of the proposed topology include high efficiency; due to lower power losses and reduced number of switching elements, high output power density realization, and reduced passive component ratings proportionally to the frequency. Additional advantages also include grid economic utilization by insuring unity power factor operation under different possible conditions and robustness since short-circuit through a leg is not possible. A high but acceptable total harmonic distortion of the generator currents is introduced in the proposed topology which can be viewed as a minor disadvantage when compared to traditional boost rectifiers. A hysteresis control algorithm is proposed to achieve lower current harmonic distortion for the rectifier operation. The rectifier topology concept, the principle of operation, and control scheme are presented. Additionally, a dc-dc converter is also employed in the rectifier-battery connection. Test results on 50-kHz power converter system are presented and discussed to confirm the effectiveness of the proposed topology for PHEV
application.
LINK ORIGINAL
http://jpe.or.kr/archives/view_articles.asp?seq=536
LINK DIRECT
http://manuscript.jpe.or.kr/ltkPSWeb/pub/pubfpfile.aspx?ppseq=536

Reduction of Total Harmonic Distortion in Inverters Driving a Compressor using Active Power Filter with Phase Delay Compensation





Reduction of Total Harmonic Distortion in Inverters Driving a Compressor
using Active Power Filter with Phase Delay Compensation
Lim,Chan-Gyu
School of Electronics Engineering, Major in Control System
Graduate School, Kyungpook National University Daegu, Korea
(Supervised by Professor Choi, Jong-Woo)


ABSTRACT
 In recent years, there has been a considerable interest in the active power filters and power quality contaminated by non-linear load. Among the power filters, a shunt active filter is most preferable to protect the consumers from the power line with an harmonic load current. This paper describes the active power filter to comply with harmonics current regulation(IEC 61000-3-12) effective for the inverter air-conditioners whose operating current is more than 16A. The validity of the proposed compensating method has been verified by the experimental results for a shunt active power filter controlled by all pass filter to compensate a phase delay of harmonics. It was shown that the total harmonic distortion (THD) of the air-conditioner inverter has been much reduced to 6% from 54%. It is expected that the proposed active power filter is effective to the competitiveness of the air-conditioner inverter and the reduction of harmonic damage such as power line loss, power device overheating.
 A thesis submitted to the Council of the Graduate School of Kyungpook National University in partial fulfillment of the requirements for the degree of Master of Science. in December, 2013.
LINK
http://www.mediafire.com/view/9d091coag56oxx6/FILTRO_ACTIVO_AR_CONDICIONADO.pdf

Harmonics and Inter-harmonics Estimation of Power Signal using Filter Banks LIN YOUNG BIN DEPARTMENT OF ELECTRICAL ENGINEERING CHUNGBK NATIONAL UNIVERSITY KOREA


ABSTRACT This paper proposes a new method which combines filter bank system and adaptive filtering for the parameters estimation of the harmonics and the inter-harmonics of power signals. The proposed method decomposes the input power signal by designing the filter bank system. This filter bank has binary tree structure, and uses the fundamental filter banks successively in each decomposing stage. The fundamental filter bank separates the odd harmonic and the even harmonic components to reduce the spectral leakage. The adaptive filter is applied to the each harmonic component for the accurate parameter estimation. And the inter-harmonic component parameters are estimated through the error signal of the adaptive filter. The amplitudes and the frequency estimation of the each harmonic and inter-harmonic are carried out by the recursive method. To demonstrate the performance of the method, computer simulations are performed to the synthesized signals.
LINK
https://www.mediafire.com/?3d1zacmct6rfwhz

sexta-feira, 26 de dezembro de 2014

R. RICHTER ELECTRICAL MACHINERY volume III TRANSFORMERS Translated from the German ilzh. NA Golubeva


R. RICHTER ELECTRICAL MACHINERY volume III TRANSFORMERS Translated from the German ilzh. NA Golubeva edited by prof. T * Petrova Approved GUUZ NKTP as textbook for energy technical colleges
LINK ORIGINAL ( FORMAT DJVU )
http://mexalib.com/download/60042

segunda-feira, 15 de dezembro de 2014

SETOR ELÉTRICO : NA LINHA DAS IMPREVISIBILIDADES PAULO LUDMER - REVISTA ELETRICIDADE MODERNA

"NINGUÉM SE ENGANE: ÁGUA E ENERGIA SERÃO MAIS CARAS E DE PLANEJAMENTO MUITO COMPLEXO ATÉ PELO MENOS 2017 "
PAULO LUDMER
JORNALISTA,ENGENHEIRO,PROFESSOR,CONSULTOR E AUTOR DE LIVROS COMO DERIÇA ELETRICA E SERTÃO ELÉTRICO
WEBSITE; www.pauloludmer.com.br
FONTE DA NOTICIA
REVISTA ELETRICIDADE MODERNA NOVEMBRO2014-ANO XLIII-EM-488
LINK REVISTA
http://www.arandanet.com.br/midiaonline/eletricidade_moderna/2014/novembro/index.html

domingo, 14 de dezembro de 2014

Harmonics Reduction in High-Efficiency Operation of Double-Conversion UPS Lorenzo Giuntini



Abstract
UPS are used to protect critical loads, and double-conversion is often the preferred choice. While
providing optimum protection, this topology offers limited efficiency. Some double-conversion UPS
feature a high-efficiency (ECO) mode, with the load normally fed via the bypass path. In this
operating mode, load current harmonics may be let through towards the utility, and may induce a high
load on the neutral conductor. In this context, this paper discusses Advanced ECO Mode topologies
that reduce neutral current and mitigate harmonics resulting from non-linear or unbalanced load.

Introduction
 Uninterruptible Power Supplies (UPS) provide power conditioning and backup power for critical and sensitive equipment, the typical example being Information Technology (IT) equipment in data centers. Double-conversion topology is often the preferred choice, especially for larger UPS installations (as a matter of fact, double conversion topology dominates the market for UPSs larger than 5 kVA used in US data centers [1]). While providing optimum protection, double conversion topology may not offer the highest efficiency: best-in-class efficiency for double conversion transformer-based UPS is around 94 %. Actual efficiency may further drop depending on UPS operating conditions, particularly the load level. In fact, UPS losses may account for 10 % of the total power consumed in a data center [2]. Given the challenges posed by greenhouse gases (GHG) emission targets, energy intensive facilities are looking at alternative UPS operating modes to increase the overall site efficiency. Some double conversion UPS feature a high-efficiency mode (typically referred to as ECO mode), where losses are greatly reduced by feeding the load via the bypass path, with resulting efficiency exceeding 98 %. A common concern is that bypass operation may expose the load to utility disturbances. To address such concerns, previous research activity focused on protection against power quality events (such as interruptions, sags, swells, spikes, etc.) during ECO mode operation. This paper takes another perspective, focusing on current harmonics and neutral current resulting from non-linear or unbalanced load. When the UPS is feeding loads with non-linear input characteristics (such as IT equipment) via the bypass path, the resulting harmonics may potentially pollute the power system. These harmonics may induce voltage distortion and increase losses, eventually leading to premature failure of electrical equipment [3]. Additionally, triplen harmonics accumulate in the neutral conductor, and combined with unbalanced loads may potentially lead to overload of the neutral conductor and overheating of the distribution transformer [4]. In this context, this paper explores Advanced ECO Mode topologies that reduce neutral conductor loading and mitigate harmonic injection on the utility supply, presenting experimental results from testing high-power UPS installations.
LINK FULL PAPER
https://copy.com/uFvkhtpuxhNUmGxz

HIGH FREQUENCY LINK UPS SYSTEM By Emad Abdulrazzaq Rasool School of Engineering and Design Department of Electrical Engineering and Electronics Brunel University UNITED KINGDOM






HIGH FREQUENCY LINK UPS SYSTEM
A thesis submitted for the degree of Master of Philosophy
 By Emad Abdulrazzaq Rasool
 School of Engineering and Design Department of Electrical Engineering and Electronics
Brunel University January 2013

ABSTRACT
The main aim of this thesis is to propose, design, simulate and build a new UPS system which can be used for compact applications. The idea of the proposed system is to operate the transformers within the UPS at high frequency so that the size and the weight are kept to minimum. In order to achieve this aim, the transformer within the UPS system is operated at high frequency; however it also carries two 50 Hz waveforms at 180 phase shift so that the transformer does not see this 50 Hz frequency. A cycloconverter is then used to reconstruct the 50 Hz waveform for the UPS output.
The UPS system is simulated using PSPICE software at high frequency link of 500 Hz, 1 kHz, 5 kHz and 10 kHz. The simulation results show that the transformer only passes the high frequency component while the 50 Hz frequency is ‘hidden’ within the transformer. The proposed UPS system is then built using MOSFETs IRF740 as the main switches for the inverter and cycloconverter circuits. A Chipkit-uno32-development-board is used to control the MOSFET switches. Simulated and practical results show the viability of the proposed UPS system.

LINK FULL THESIS
http://bura.brunel.ac.uk/bitstream/2438/7246/1/FulltextThesis.pdf

Design of Robust Controller for Single-Phase Double-Conversion UPS System Seung-Beom Lim, Young-Min Seol, Sang-Hoon Kim, Jin-Woo Lee, and Soon-Chan Hong Dankook University, Korea, Kangwon National University, Korea





Design of Robust Controller for Single-Phase
Double-Conversion UPS System

Seung-Beom Liml, Young-Min Seo, Sang-Hoon Kim, Jin-Woo Lee, and Soon-Chan Hongl
 Dankook University, Korea,  Kangwon National University, Korea, Doowon Technical College,
Koreabus1327@hotmail.com, maniyan@nate.com, kshoon@kangwon.ac.kr, jinwoo@doowon.ac.kr, schong@dku.edu

Abstract-UPS is largely divided into passive-standby, line interactive,
and double-conversion types. In general, a double conversion
type is used at a site requiring a high reliability. The
main function of the double-conversion UPS is providing the
constant voltage, constant frequency, regardless of the linear or
non-linear load and variation of the load. In this paper, the
robust controller of the single phase double-conversion UPS is
designed and its performance is verified by both simulations and
experimentation.


sábado, 13 de dezembro de 2014

terça-feira, 9 de dezembro de 2014

WORKSHOP COMSOL ENG. ALISSON ROMAN -CAMPINAS SÃO PAULO-09 DECEMBRO 2014





Eng.Tiago Davi Curi Busarello - Doutorado-CONDICIONAMENTO DE ENERGIA ELÉ...




VISITA AO LABORATORIO DE PESQUISA CONDICIONAMENTO ENERGIA
 TESE DE DOUTORADO DO MESTRE ENG. TIAGO CURI BUSARELLO
 LABORATÓRIO DE CONDICIONAMENTO DE ENERGIA ELÉTRICA - LCEE- UNICAMP-BRASIL AV. ALBERT EINSTEIN 400 -CAMPINAS - SP-BRASIL
 DEPARTAMENTO DE SISTEMAS E ENERGIA - DSE
 ATIVIDADES DESENVOLVIDAS NO LCEE
 São definidos como Condicionamento da Energia Elétrica os procedimentos e tecnologias necessários para: i) minimizar o conteúdo harmônico da tensão e da corrente; ii) maximizar o fator de potência das cargas; iii) estabilizar a tensão de suprimento; iv) minimizar a geração de componentes de alta freqüência; v) fornecer de modo adequado a alimentação para a carga; iv) flexibilizar o uso do sistema de energia elétrica.

segunda-feira, 8 de dezembro de 2014

Design and Implementation of the 40kV, 13kW High Efficiency High Voltage Capacitor Charger














































































































This paper deals with design and implementation of the 40kV, 13kW high-efficiency high-voltage capacitor charger for the pulsed power modulator. The proposed capacitor charger consists of the 24 series-connected power cells, a resonant inverter, and a distinctive high-voltage transformer. Moreover, third winding of high-voltage transformer is added to compensate voltage unbalance of each power cell automatically, and the relay mode operation is suggested to generate minimum 1kV even at light load condition while restricting the maximum switching frequency. In this paper, the operation principles of series-loaded resonant converter are explained and analyzed. In addition, the mode analysis of the resonant converter operating at above resonance frequency are conducted. Based on these analysis, the design of the 40kV, 13kW capacitor charger is suggested. To verify the proposed design, PSpice simulation modeling was performed, and the reliability and robustness of the proposed high voltage capacitor charger is proved through experimental results. In future, the pulsed power modulator based on the proposed high voltage capacitor charger will be developed by connecting IGBT switches between the power cells.