“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”

OBRIGADO DEUS PELA VIDA,PROTEGENOS E GUARDANOS DE TODO MAL


AUTOR DO BLOG ENG. ARMANDO CAVERO MIRANDA SAO PAULO BRASIL

segunda-feira, 23 de dezembro de 2013

Principles of Transformer Design by Alfred Still

A Book which deals exclusively with the theory and design of alternating current transformers is not likely to meet the requirements of a College text to the same extent as if its scope were broadened to include other types of electrical machinery. On the other hand, the fact that there may be a limited demand for it by college students taking advanced courses in electrical engineering has led the writer to follow the method of presentation which he has found successful in teaching electrical design to senior students in the school of Electrical Engineering at Purdue University. Stress is laid on the fundamental principles of electrical engineering, and an attempt is made to explain the reasons underlying all statements and formulas, even when this involves the introduction of additional material which might be omitted if the needs of the practical designer were alone to be considered.
LINK1
http://www.forgottenbooks.org/books/Principles_of_Transformer_Design_1000221063
LINK2-FULL TEXT
https://archive.org/download/principlesoftran00stilrich/principlesoftran00stilrich.pdf 

Photovoltaic energy applications: state-of-the-art and perspectives Plenary Sessions BRASIL POWER ELECTRONICS CONFERENCE 2013

Photovoltaic energy applications: state-of-the-art and perspectives

(Download Presentation)
Prof. Roberto Ziles, Ph.D.
University of São Paulo, Brazil
Oct. 31th, Thursday, 8:30 am - 10:00 am
Abstract
The lecture devotes attention to the current situation of photovoltaic energy applications, discussing aspects such as the PV market characterization, technologies, costs and trends.
The lecture also describes the main configurations of photovoltaic systems and their integration into the national context, as well as major advances made in the country to provide the integration of distributed generation photovoltaic systems.
Biography
Roberto Zilles received his PhD in Telecommunications Engineering with specialty in Photovoltaic Systems from “Universidad Politecnica de Madrid” (1993) and the degree of “Livre Docência” with emphasis in renewable energy from São Paulo State University (2006). Currently, he is an Associate Professor and head of Scientific Division of Energy and Environment, Institute of São Paulo State University. Dr. Zilles is an Editorial Board member of “Progress in Photovoltaics: Research and Applications” journal, head of Brazilian Photovoltaic Energy Association, and vice head of Amazon National Institute of Science and Renewable Energy Technologies.

sábado, 21 de dezembro de 2013

A New Three-Phase Parallel Active Power Filter with Outages and PCC Voltage Compensation




A New Three-Phase Parallel Active Power Filter
with Outages and PCC Voltage Compensation
by
WOO-CHEOL, LEE
Under the supervision of
Prof. DONG-SEOK HYUN, Ph.D.
Dept. of Electrical Engineering
The Graduate School of Hangyang University
This paper is a research on a new three-phase parallel active
power filter with outages and PCC voltage compensation under the
utility problems caused by the proliferation of non-linear loads such
as harmonics, increment of reactive power, voltage variation, and
blackouts. For these purposes, this paper presents (i) the optimal
design of parallel active power filter (ii) the modified PWM
modulation strategy which can operate the power conversion
system by using the single current sensor (iii) the detection method
of negative sequence and control scheme under the unbalanced load
condition (iv) the control method of constant PCC voltage (v) UPS
control method caused by blackouts in typical distribution systems
and the relations of each scheme.
 In a design method of the parallel active filter, an analytic model
on active filter is proposed. For this purpose, control circuit, power
 circuit, IGBT drive, and design method of the passive filter are
proposed. In a modified PWM modulation strategy, a technique for
reconstructing converter line currents using the information from a
single current sensor in the DC-link of a converter and comparative
evaluation of the performance of single sensor control techniques in
the DC-link for voltage-source PWM converters is presented. And
when 3f input currents cannot be reconstructed, three methods to
acquire the DC-link current are also proposed.
LINK
https://www.mediafire.com/?1u16ro18vksutdg

Design of Advanced Voltage Controller for Three-Phase UPS inverters by KYUNG-HWAN KIM


Design of Advanced Voltage Controller for
Three-Phase UPS inverters
by
KYUNG-HWAN KIM
Under the supervision of
Prof. DONG-SEOK HYUN, Ph.D.
Dept. of Electrical Engineering
The Graduate School of Hanyang University
 ABSTRACT

Inverter system, which uses LC component as the output filter, is essential for a UPS (Uninterruptible Power supply), UPQC (Universal Custom Power Conditioner) and PCS (Power Conditioning System) for the photovoltaic power system. This paper presents DSP (Digital Signal Processor) controlled voltage controller for a 3-phase UPS inverter, which is able to compensate the voltage distortions due to unbalanced and nonlinear loads. The paper discussed the problem of conventional control schemes for the compensation of voltage distortion when they are applied to UPS inverter, and proposes advanced synchronous reference frame control scheme which is able to overcome the problem. In order to solve the problem of low damping ratio of LC filter, the inverter current feed-forward compensator including the selection of the feed-forward gain is proposed. And the digital filter for a compensation of the voltage distortion due to unbalanced and nonlinear loads is also proposed, which makes PI controllers in the synchronous reference frame are able to operate with DC values even under nonlinear and unbalanced load, likewise ensures PI controllers are able to provide zero steady state error. In order to improve the practical usability of the proposed scheme in the paper, the realization of the PLL and the parallel operation, which are essential for UPS, using the proposed controller is also presented. Especially, this paper shows that the feed-forward compensation of the inverter current and the PWM synchronization method proposed in the paper ensures a high precise load-sharing performance in parallel operation of inverter system. The effectiveness of the proposed scheme has been investigated and verified in digital simulation. This thesis also investigates the digital implementation of the proposed systems and all of the related theoretical concepts and control systems have been verified in experimental prototype of the UPS systems.
LINK THESIS
http://library-english.hanyang.ac.kr/eng/index.jsp
DOWNLOAD
https://www.mediafire.com/?vyf940qs5fcc55l

CONDICIONAMENTO DE ENERGIA E GRUPOS GERADORES REVISTA SETOR ELETRICO NOVEMBRO 2013-PARTE1



quinta-feira, 19 de dezembro de 2013

RWTH Aachen University Clase Abierta: Fabricación de Maquinaria

China's moon rover separates from moon lander



CHINA ATERIZOU COM SUCESSO SUA PRIMEIRA SONDA ESPACIAL NÃO TRIPULADA NA LUA,CHINA E APENAS O TERCEIRO PAIS A POUSAR NA LUA,SEGUINDO OS EUA E A ANTIGA UNIÃO SOVIETICA,QUE TANTO REALIZOU AS TAREFAS DECADAS ATRAS. "E UMA CONQUISTA DIGNA DE RESPEITO",DISSE JOHN LOGSDON,PROFESSOR EMERITO DA UNIVERSIDADE DE GEORGE WASHINGTON,QUE HA MUITO TEM MONITORADO POLITICA ESPACIAL.
'CHANG-3 E IMPRESSIONANTE COMO O PRIMEIRO POSSO NA LUA EM QUASE QUATRO DECADAS,CAINDO EM UM LUGAR QUE NÃO FOI EXPLORADO E USANDO INSTRUMENTAÇÃO CIENTIFICA RELATIVAMENTE AVANÇADA.

terça-feira, 17 de dezembro de 2013

Analysis of the Internal Electrical Characteristics of Electronic Power Transformers Yang Yi*, Cheng-Xiong Mao*, Dan Wang†, and Ji-Ming Lu**

Analysis of the Internal Electrical Characteristics of Electronic Power Transformers Yang Yi*, Cheng-Xiong Mao*, Dan Wang†, and Ji-Ming Lu** *State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, China †**College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, China.
Abstract The modularized subunit of an electronic power transformer (EPT) is a series connection of two H-bridge voltage-source converters and a DC–DC converter with a high-frequency isolation transformer (HFIT). On the basis of cascading and paralleling the modularized subunits, EPT can be used in high-voltage and large-current applications in the power system. This paper discusses the steady state analysis of the modularized subunit of EPT. Theoretical analysis considers the influences of the two H-bridge voltage-source converters on the two sides of the DC–DC converter. We deduce the formulas of the theoretical calculation on the internal electrical characteristics of EPT (e.g., the voltages of the DC-bus capacitor and the primary side peak current of the HFIT). This paper provides guidance on the design and selection of EPT key elements (e.g., the DC-bus capacitors and HFIT). Experimental results are obtained from a single subunit of a laboratory model rated at 962 V, 15 kVA. All calculations, simulations,and experiments confirm the theoretical analysis of the subunit of EPT.
LINK
 http://jpe.or.kr/archives/view_articles.asp?seq=776

New Isolated Single-Phase AC-DC Converter for Universal Input Voltage Ming-Rong Lee*, Lung-Sheng Yang†, and Chia-Ching Lin*

New Isolated Single-Phase AC-DC Converter for Universal Input Voltage Ming-Rong Lee*, Lung-Sheng Yang†, and Chia-Ching Lin* *†Dept. of Electrical Engineering, Far East University, Tainan City, Taiwan Abstract This paper investigates a new isolated single-phase AC-DC converter, which integrates a modified AC-DC buck-boost converter with a DC-DC forward converter. The front semi-stage is operated in discontinuous conduction mode (DCM) to achieve an almost unity power factor and a low total harmonic distortion of the input current. The rear semi-stage is used for step-down voltage conversion and electrical isolation. The front semi-stage uses a coupled inductor with the same winding-turn in the primary and secondary sides, which is charged in series during the switch-on period and is discharged in parallel during the switch-off period. The discharging time can be shortened. In other words, the duty ratio can be extended. This semi-stage can be operated in a larger duty-ratio range than the conventional AC-DC buck-boost converter for DCM operation. Therefore, the proposed converter is suitable for universal input voltage (90~264 Vrms) and a wide output-power range. Moreover, the voltage stress on the DC-link capacitor is low. Finally, a prototype circuit is implemented to verify the performance of the proposed converter.
 LINK
http://jpe.or.kr/archives/view_articles.asp?seq=760

Modeling and Control Method for High-power Electromagnetic Transmitter Power Supplies Fei Yu† and Yi-ming Zhang*


Modeling and Control Method for High-power Electromagnetic Transmitter Power Supplies Fei Yu† and Yi-ming Zhang* †*College of Electronic Information and Control Engineering, Beijing University of Technology, Beijing, China
LINK
http://jpe.or.kr/archives/view_articles.asp?seq=769

Study on the Influence of Distribution Lines to Parallel Inverter Systems Adopting the Droop Control Method Xuan Zhang*, Jinjun Liu*, Zhiyuan You†, and Ting Liu*


Study on the Influence of Distribution Lines to Parallel Inverter Systems Adopting the Droop Control Method Xuan Zhang*, Jinjun Liu*, Zhiyuan You†, and Ting Liu* *†Dept. of Electronic Engineering, Xi’an Jiaotong University, Xi'an, China Abstract This paper takes into account the influence of the different impedances of distribution lines on power distribution among inverters when the inverters are paralleled with the droop control method. The impact of distribution lines on the power distribution of inverters can be divided into two aspects. Firstly, since the distributed generators are in low voltage grids, there is resistive impedance in the distribution lines, which will cause control coupling and reduce system stability. The virtual negative resistive impedance of inverters is adopted in this paper to neutralize the resistive element of distribution lines and thus make the distribution line impedance purely inductive. Secondly, after solving the resistive impedance problem, the difference in the inductive impedance value of distribution lines due to the low density of distributed generators will cause an unequal share of reactive power. With regards to this problem, modification is put forward for the droop control strategy to share the reactive power equally. The feasibility of the design is validated by simulation and experimental results.
LINK
http://jpe.or.kr/archives/view_articles.asp?seq=771

Control Method for Reducing the THD of Grid Current of Three-Phase Grid-Connected Inverters Under Distorted Grid Voltages


Control Method for Reducing the THD of Grid Current of Three-Phase Grid-Connected Inverters Under Distorted Grid Voltages Thanh-Vu Tran*, Tae-Won Chun†, Hong-Hee Lee*, Heung-Geun Kim**, and Eui-Cheol Nho*** *†Dept. of Electrical Engineering, University of Ulsan, Ulsan, Korea **Dept. Of Electrical Engineering, Kyungpook National University, Daegu, Korea ***Dept. of Electrical Engineering, Pukyong National University, Busan, Korea
Abstract This paper proposes a control method for reducing the total harmonic distortion (THD) of the grid current of three-phase grid-connected inverter systems when the grid voltage is distorted. The THD of the grid current caused by grid voltage harmonics is derived by considering the phase delay and magnitude attenuation due to the hardware low-pass filter (LPF). The Cauchy-Schwarz inequality theory is used in order to search more easily for the minimum point of the THD. Both the gain and angle of the compensation voltage at the minimum point of the THD of the grid current are derived with the variation of cut-off frequencies of the hardware LPF. Simulation and experimental results show the validity of the proposed control methods.
LINK
 http://jpe.or.kr/archives/view_articles.asp?seq=772

The Effect of Transformer Leakage Inductance on the Steady State Performance of Push-pull based Converter with Continuous Current Qian Chen†, Trillion Q. Zheng*, Yan Li*, and Tiancong Shao*


The Effect of Transformer Leakage Inductance on the Steady State Performance of Push-pull based Converter with Continuous Current Qian Chen†, Trillion Q. Zheng*, Yan Li*, and Tiancong Shao* †*School of Electrical and Engineering, Beijing Jiaotong University, Beijing, China Abstract As a result of the advantages such as high efficiency, continuous current and high stability margin, push-pull converter with continuous current (PPCWCC) is competitive for battery discharge regulator (BDR) which plays an important role in power conditioning unit (PCU).Leakage inductance yields current spike in low-ripple current of PPCWCCs. The operating modes are added due to leakage inductance. Therefore the steady state performance is affected, which is embodied in the spike of low-ripple current. PPCWCCs which are suitable for BDR can be separated into three types by current spike characteristics. Three representative topologies IIs1, IIcb2 and Is3 are analyzed in order to investigate the factors on the magnitude and duration of spike. Equivalent current sampling method (ECSM) which eliminates the sampling time delay and achieves excellent dynamic performance is adopted to prevent the spike disturbance on current sampling. However, ECSM reduces the sampling accuracy and telemetry accuracy due to neglecting the spike. In this paper, ECSM used in PPCWCCs is summarized. The current sampling error is analyzed in quality and quantity, which provides the foundation for offsetting and enhancing the telemetry accuracy. Finally, current sampling error rate of three topologies is compared by experiment results, which verify the theoretical analysis.
LINK
http://jpe.or.kr/archives/view_articles.asp?seq=735

Design of an LCL-Filter for Three-Parallel Operation of Power Converters in Wind Turbines Hae-Gwang Jeong*, Dong-Keun Yoon**, and Kyo-Beum Lee†

Design of an LCL-Filter for Three-Parallel Operation
of Power Converters in Wind Turbines
Hae-Gwang Jeong*, Dong-Keun Yoon**, and Kyo-Beum Lee†
†*Department of Electrical and Computer Engineering, Ajou University, Suwon, Korea
**Research Group, LG Innotek Co., Ltd., Ansan, Korea

This paper proposes a design scheme for an LCL-filter used for the three-parallel operation of the power converters in high-capacity wind turbines. The designs of the power devices and grid connected filter are difficult due to the high level voltages and currents in huge-capacity wind turbines. To solve these problem, this paper presents three-parallel operation and LCL-filter design techniques optimized by parallel operation. Furthermore, the design of an inverter side inductance of the LCL-filter is discussed in detail considering the switching modulation method. Simulation and experimental results demonstrate the validity of the designed filter and wind turbines.
LINK
http://jpe.or.kr/archives/view_articles.asp?seq=744
https://www.mediafire.com/?f2tlal6acrdao3a

GRAU DE PROTEÇÃO IP PARA EQUIPAMENTOS ELÉTRICOS

http://marcussalesconsultoria.files.wordpress.com/2013/01/tabela-ip-indice-de-protec3a7c3a3o1.jpg

segunda-feira, 16 de dezembro de 2013

Parallel Operation of Three-Phase Four wire UPS using Droop Control ( Hyunseob Kim․Jungho Han․Joong-Ho Song )

Parallel Operation of Three-Phase Four wire UPS using Droop Control

* Main author:Dept. of Railway Electrical and
Signaling Engineering, Seoul National
University of Science and Technology,
Candidate of MS
** Corresponding author:Dept. of Electrical and
Information Engineering, Seoul National
University of Science and Technology,
Professor
Tel:02-970-6415, Fax:02-978-2754
E-mail:joongho@seoultech.ac.kr
 Abstract
A new droop control method which can be applied to 3-phase 4-wire uninterruptible power supply is
proposed in this paper. The droop control method for parallel operation is very attractive one as UPS
parallel operation can be carried out without any data communication devices provided among UPS
systems connected, but it reportedly shows a PnP(plug-and-play) problem. A basic reason why a
circulating current could flow among parallel-connected UPS systems is clearly investigated as well
when droop-controlled-ups systems are operated in the manner of PnP. The proposed algorithm is
deduced from the investigated result and is basically structured to keep a balanced frequency and
balanced voltage profile against power variation. This paper shows that balanced parallel operation of
droop control method can be obtained under unbalanced load as well as balanced load conditions .when PnP operation is needed and load change occurs.
LINK
http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=JMJGCE_2013_v27n4_88

https://www.mediafire.com/?gyedgrq3fd38alx

Power Factor Correction of Single-phase Boost Converter for Low-cost Type UPS Configuration Jong-Chan Park․Jin-Geun Shon


Power Factor Correction of Single-phase Boost Converter for Low-cost Type UPS Configuration 박 종 찬*․손 진 근† (Jong-Chan Park․Jin-Geun Shon) The Transactions of the Korean Institute of Electrical Engineers Vol. 62P, No. 3, pp. 145~150, 2013

 Abstract -A novel AC to DC PWM converters with unity input power factor are proposed to overcome the above shortcoming. The main function of these converters is to shape the input line current to force it exactly in phase with the input AC voltage. Therefore, the input power factor can be improved to near unity and the input current harmonics can be eliminated. In this paper, half-bridge converter with two active switches and two diodes are utilized for low-cost type UPS configuration. By having only two semiconductors in the current path at any time, losses can be reduced over the conventional boost topology. Also, this converter provides controllable dc-link voltage, high power factor, and low cost type converter by simple power circuits. Simulation results show that the proposed half-bridge converter/inverter control technique can be applied to single-phase low-cost type UPS systems successfully.
LINK
http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=DHJGHA_2013_v62n3_145

https://www.mediafire.com/?fqu14xattw5nwkp

LLC Resonant Converter design for Uninterruptible Power Supply Battery Discharger



Abstract - An Uninterruptible Power Supply(UPS) is a system designed to deliver energy during accidents that the AC mains is out of its acceptable limits, without interruption of power flow through the load. Battery Discharger is the device to supply high quality power to the Inverter, when accidents occur, such as Power Failure. The Battery Discharger should have a fast response characteristics. The LLC resonant converter for UPS battery discharger is proposed. The proposed Battery Discharger offers substantial improvements in efficiency, size and cost. The proposed Battery Discharger of UPS approach is a good solution for high power applications above KW. To verify the validity of proposed Battery Discharger, simulations and experiments are carried out. Paper number: TKPE-2013-18-3-6 ISSN: 1229-2214 ✝ Corresponding author: pdpljy@mju.ac.kr, Dept. of Electrical Engineering, MyongJi University Tel: +82-31-330-6357 Fax: +82-31-330-6977 1 Dept. of Electrical Engineering, Myongji University 2 Eon Co., Ltd Manuscript received Oct. 5, 2012; accepted Feb. 20, 2013 ─ 본 논문은 2012년 전력전자학술대회 외부장학금 수혜논문임
DOWNLOAD
 http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=JRJJC3_2013_v18n3_240

https://www.mediafire.com/?143thdj9xfgg61s

A Controller Design for a Stability Improvement of an On-Board Battery Charger Hae-Gwang Jeong* and Kyo-Beum Lee†

A Controller Design for a Stability Improvement of an On-Board
Battery Charger
Hae-Gwang Jeong* and Kyo-Beum Lee†
Corresponding Author: Department of Electrical and Computer
Engineering, Ajou University, Suwon, Korea. (kyl@ajou.ac.kr)
* Dept. of Electrical and Computer Engineering, Ajou University,
Suwon, Korea. (lite88@ajou.ac.kr)
Received: May 27, 2013; Accepted: June 7, 2013

Abstract – This paper proposes the controller design for a stability improvement of an on-board
battery charger. The system is comprised of a power factor correction (PFC) circuit and phase shift
full-bridge DC-DC converter. The PFC circuit performs the control of the DC-link voltage and the
input power factor. The DC-DC converter regulates the voltage and the current in the battery using the
DC-link voltage. This paper proposes the design method of PI controller for the PFC circuit using a
small signal model. The analysis and design of a type-three controller for the DC-DC converter is also
presented. A simulation and experiment has been performed on the on-board battery charger and their
results are presented to verify the validity of the proposed system.
DOWNLOAD
http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=E1EEFQ_2013_v8n4_951

https://www.mediafire.com/?b466cwi2g7t404z

A Three-Phase High Frequency Semi-Controlled Battery Charging Power Converter for Plug-In Hybrid Electric Vehicles

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
applications.
LINK DOWNLOAD
http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=E1PWAX_2011_v11n4_490

A Study on the Hot Spot Temperature in 154kV Power Transformers Dong-Jin Kweon†, Kyo-Sun Koo*, Jung-Wook Woo* and Joo-Sik Kwak*

A Study on the Hot Spot Temperature in 154kV Power Transformers
Dong-Jin Kweon†, Kyo-Sun Koo*, Jung-Wook Woo* and Joo-Sik Kwak*
Abstract – The life of a power transformer is dependent on the life of the cellulose paper, which
influenced by the hot spot temperature. Thus, the determination of the cellulose paper’s life requires
identifying the hot spot temperature of the transformer. Currently, however, the power transformer
uses a heat run test is used in the factory test to measure top liquid temperature rise and average
winding temperature rise, which is specified in its specification. The hot spot temperature is calculated
by the winding resistance detected during the heat run test. This paper measures the hot spot
temperature in the single-phase, 154kV, 15/20MVA power transformer by the optical fiber sensors and
compares the value with the hot spot temperature calculated by the conventional heat run test in the
factory test. To measure the hot spot temperature, ten optical fiber sensors were installed on both the
high and low voltage winding; and the temperature distribution during the heat run test, three
thermocouples were installed. The hot spot temperature shown in the heat run test was 92.6℃ on the
low voltage winding. However, the hot spot temperature as measured by the optical fiber sensor
appeared between turn 2 and turn 3 on the upper side of the low voltage winding, recording 105.9℃.
The hot spot temperature of the low voltage winding as measured by the optical fiber sensor was 13.3℃
higher than the hot spot temperature calculated by the heat run test. Therefore, the hot spot factor (H)
in IEC 60076-2 appeared to be 2.0.
LINKS DOWNLOAD
http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=E1EEFQ_2012_v7n3_312

https://www.mediafire.com/?skoajdlchdtoj0c

Implementation of a High Efficiency Grid-Tied Multi-Level Photovoltaic Power Conditioning System Using Phase Shifted H-Bridge Modules

Implementation of a High Efficiency Grid-Tied
Multi-Level Photovoltaic Power Conditioning
System Using Phase Shifted H-Bridge Modules
Jong-Pil Lee†, Byung-Duk Min**, and Dong-Wook Yoo*
†*Power Conversion Research Center, Korea Electrotechnology Research Institute, Changwon, Korea
**Green Power Co. Ltd, Suwon, Korea
Abstract
This paper proposes a high efficiency three-phase cascaded phase shifted H-bridge multi-level inverter without DC/DC
converters for grid-tied multi string photovoltaic (PV) applications. The cascaded H-bridge topology is suitable for PV
applications since each PV module can act as a separate DC source for each cascaded H-bridge module. The proposed phase
shifted H-bridge multi-level topology offers advantages such as operation at a lower switching frequency and a lower current
ripple when compared to conventional two level topologies. It is also shown that low ripple sinusoidal current waveforms are
generated with a unity power factor. The control algorithm permits the independent control of each DC link voltage with a
maximum power point for each string of PV modules. The use of the controller area network (CAN) communication protocol for
H-bridge multi-level inverters, along with localized PWM generation and PV voltage regulation are implemented. It is also
shown that the expansion and modularization capabilities of the H-bridge modules are improved since the individual inverter
modules operate more independently. The proposed topology is implemented for a three phase 240kW multi-level PV power
conditioning system (PCS) which has 40kW H-bridge modules. The experimental results show that the proposed topology has good performance.
LINKS DOWNLOAD
http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=E1PWAX_2013_v13n2_296

domingo, 15 de dezembro de 2013

Transformerless three-phase on-line UPS with high performance

Transformerless three-phase on-line UPS with
high performance
E.-H. Kim J.-M. Kwon B.-H. Kwon
Department of Electronic and Electrical Engineering, Pohang University of Science and Tech, Republic of Korea
E-mail: znight@postech.ac.kr
Abstract: A transformerless three-phase on-line uninterruptible power supply (UPS) is proposed. The proposed
UPS is composed of a rectifier, an inverter and a battery charger/discharger. The rectifier regulates a DC-link
voltage and performs power factor correction. On the other hand, the inverter provides a regulated sinusoidal
output voltage and has the current-limiting capability for an impulsive load. The battery charger/discharger
reduces the number of battery and supplies the power demanded by the load in the event of the input
power failure or abrupt decrease of the input voltage. Since both neutral lines of the input and output
voltages are connected at the centre of the DC-link, the need for an isolation transformer is eliminated and
the size, weight and cost of the system are significantly reduced. Additionally, new control algorithms of the rectifier, the charger/discharger and the inverter are proposed.
LINK
http://www.mediafire.com/view/7yl5uqoj5e3eq4s/TRANSFORMERLESS-UPS.pdf

Novel Two-Stage High-Power-Factor Electronic Ballast CHUN YUAN CHRISTIAN UNIVERSITY

Abstract

In this thesis, electronic ballast with power factor correction for high intensity discharging (HID) lamp is presented. The proposed topology is a two-stages circuit that requires only one switch and one inductor for each stage. Power factor correction (PFC) stage is boost dc-to-dc converter operating in continuous conduction mode (CCM) to achieve low total harmonic distortion (THD) and proper output characteristics over a wide range of load (10% ~ 90% full load).
This control implementation for against broken lamp can be easily implemented with the proposed circuitry. The high-frequency supply the lamp is given by the flyback converter. Input AC voltages ranges from 90V~260V are allowable for our system with a low DC bus voltage below 450V. It is suitable for electronic ballast with medium power HID lamp. The topologies could work under the circumstance of two 250W fluorescent lamps at 66 KHz switching frequency.
LINK
https://www.mediafire.com/?bc4y0332flfxltc

A STUDY OF CHARGING EQUALIZATION AND DISCHARGING POWER MANAGEMENT FOR SERIES AND PARALLEL CONNECTED BATTERY PACK

A STUDY OF CHARGING EQUALIZATION
AND DISCHARGING POWER MANAGEMENT FOR SERIES AND
PARALLEL CONNECTED BATTERY PACK

研 究 生: 蔡志明    Jr-Ming Tsai
指導教授: 李清元教授    Prof. Ching-Yuan Lee

Master Thesis Department of Electrical Engineering Tatung University

ABSTRACT
ABSTRACT

The object of this paper is to research the methodology of charging equalization and
discharging power management of the series and paralleled connected battery sets under the
considerations of the safety, economics and practicality to improve the overall battery sets
efficiency.  The battery management system used the isolation method to ensure the charging
equalization of batteries; and to protect from the abnormal situation during discharging of the
series-connected battery sets.  As for the parallel-connected battery sets, this paper proposes
a multi-mode chopper.  It will enable to control and distribute the output current from each
battery.
The serial and parallel connection scheme uses two batteries as the smallest unit.  The number of batteries may be expanded at will.  The system performs the charging and discharging tests of the serial and parallel connected GS LC18650 1800mAh lithium battery sets.  Finally, a single-chip microprocessor, PIC16F877 is use to implement the control method of the proposed system. Via the experimentation, it proofs that the methods can performs its feasibility and good characteristics as anticipated.

LINK FULL THESIS

https://www.mediafire.com/?rhvvhjqnr3io4ug

domingo, 1 de dezembro de 2013

AVALIAÇÃO DAS INSTALAÇÕES ELÉTRICAS DE CENTRO CIRÚRGICO. ESTUDO DE CASO: HOSPITAL UNIVERSITÁRIO DA UFMS.


UNIVERSIDADE FEDERAL DE MATO GROSSO DO SUL
PROGRAMA DE PÓS-GRADUAÇÃO EM ENGENHARIA
ELÉTRICA

AVALIAÇÃO DAS INSTALAÇÕES ELÉTRICAS DE
CENTRO CIRÚRGICO.
ESTUDO DE CASO: HOSPITAL UNIVERSITÁRIO
DA UFMS.
Dissertação submetida à
Universidade Federal de Mato Grosso do Sul
como parte dos requisitos para a
obtenção do grau de Mestre em Engenharia Elétrica
JOÃO CESAR OKUMOTO
LINK
http://repositorio.cbc.ufms.br:8080/jspui/bitstream/123456789/646/1/João Cesar Okumoto.pdf 
 

domingo, 24 de novembro de 2013

NORMA BRASILEIRA NBR 5410

INSTALAÇOES ELETRICAS BASICAS

ATERRAMENTO ELÉTRICO

PAGINA WEB ORIGINAL
http://dicasdesomeluz.blogspot.com.br/2012/08/aterramento-eletrico-como-funciona-e.html



ATERRAMENTO ELÉTRICO


01 - Mas o que é o “terra”?
02 - Qual a diferença entre terra,  neutro, e massa(Carcaça do Equipamento)?
03 - Quais são as normas que devo seguir para garantir um bom aterramento?
   Bem, esses são os tópicos que este artigo tentará esclarecer. É fato que o assunto "aterramento" é bastante vasto e complexo, porém, aqui vai algumas normas e regras básicas.


 Mas o que é o “terra”?
O aterramento elétrico (‘’Terra’’) tem três funções principais:
   A  –  Proteger o usuário do equipamento das descargas atmosféricas, através da viabilização (qualidade) de um caminho alternativo para a terra, de descargas atmosféricas.
   B  – “Descarregar” cargas estáticas acumuladas nas carcaças das máquinas ou equipamentos para a terra.
  C  – Facilitar o funcionamento dos dispositivos de proteção (fusíveis, disjuntores, etc.), através da corrente desviada para a terra.
  Veremos, mais adiante, que existem várias outras funções para o aterramento elétrico, até mesmo para eliminação de EMI (interferências eletromagnéticas), porém essas três acima são as mais fundamentais.
Qual a diferença entre terra,  neutro, e massa?
   Antes de falarmos sobre os tipos de aterramento, devemos esclarecer (de uma vez por todas !) o que é terra, neutro, e massa. 
   Na figura 1 temos um exemplo da ligação de um PC à rede elétrica, que possui três fases , e um neutro.
   Essa alimentação é fornecida pela concessionária de energia elétrica, que somente liga a caixa de entrada ao poste externo se  houver uma haste de aterramento padrão dentro do ambiente do usuário.     
   Além disso, a concessionária também exige dois disjuntores de proteção.
  Teoricamente, o terminal neutro da concessionária deve ter potencial igual a zero volt. Porém, devido ao desbalanceamento nas fases do transformador de distribuição, é comum esse terminal (Neutro) tender a assumir potenciais diferentes de zero. O desbalanceamento de fases ocorre quando temos por exemplo o som bifásico (2 fases) ou monofásico (1 fase e Neutro) e as luzes trifásicas, ligadas em um mesmo link (transformador) .
 Obs : Você pode ver se todo seu sistema esta desbalanceado ou não  com um alicate amperímetro , medindo fase por fase .
   Outro exemplo é um transformador que alimenta, em um setor seu, uma residência comum (fase 1) , e no outro setor, um pequeno supermercado (fase 2) . Essa diferença de demanda, em um mesmo link (transformador) , pode fazer com que o neutro varie seu potencial (flutue) .
  Para evitar que esse potencial “flutue”, ligamos (logo na entrada) o fio neutro a uma haste de terra. Sendo assim, qualquer potencial que tender a aparecer será escoado para a terra.
 Ainda analisando a figura 1 , vemos que o PC está ligado em uma fase e o neutro.
  Mas, ao mesmo tempo, ligamos sua carcaça (terra) através de outro condutor (fio) na mesma haste, e damos o nome desse condutor de “terra” (fio terra) .
LEIA O ARTIGO COMPLETO EM 

SATELITE BRASILEIRO LANÇAMENTO 2016 João Luiz Ramalho de Castro

quarta-feira, 20 de novembro de 2013

Grids First return on experience on Smart Grids Demonstrations emergence of new System of systems architectures

Grids First return on experience on Smart Grids Demonstrations emergence of new System of systems architectures from armando cavero on Vimeo.

EPE 2013 ECCE EUROPE LILLE FRANCE 15 EUROPE CONFERENCE ON POWER ELECTRONIS AND APPLICATIONS Grids: First return on experience on Smart Grids Demonstrations : emergence of new System of systems architectures by Laurent Schmitt, Alstom, France

EPE2013 -ECCE EUROPE Grids Smart Grids large scale experimentation in Vendée and future marke...



Grids: Smart Grids : large scale experimentation in Vendée and future markets for power electronics
by Nicolas Gente, SYDEV Vendée, France

15th EUROPEAN CONFERENCE ON POWER ELECTRONICS AND APPLICATIONS

Paper VD_020966_mohamed azab_iecon2013

Die Wechselstromtechnik Arnold, Engelbert, 1856-1911, ed; La Cour, Jens Lassen, 1876-; Fraenckel, Alfred

ELEKTRONIK-TUTORIAL 15/3: Elektromotoren --- Arten, Eigenschaften und An...

ELEKTRONIK-TUTORIAL 17: Transformatoren, Übertrager

WorldSkills Leipzig 2013 / Das Finale, Sendung 5



Viele Emotionen beim Finale der WorldSkills 2013 in Leipzig. Jeder Teilnehmer gab noch einmal alles. Zusammen mit Maren Ottens, unserer Dekorationsmalerin im deutschen Nationalteam, werfen wir einen Blick auf die letzten Wettkampfminuten unserer Mannschaft, die für Medaillenplätze entscheidend sein könnten.

sábado, 9 de novembro de 2013

Tecnologia de veículos elétricos

MOV02972 - Apresentação no COBEP 2013 de Adriano Ruseler no tema capacit...



Apresentação da defesa de qualificação de Adriano Ruseler



A Sub-coordenadora do Programa de Pós-Graduação em Engenharia Elétrica, Profª. Jacqueline Gisele Rolim, conforme resolução interna nº. 018/PPGEEL/97, aprovada em reunião do colegiado em 17/12/97, aprovou no dia 25 de Setembro 2013, a indicação de Banca Examinadora de defesa de exame de qualificação do aluno Adriano Ruseler cujo título é "Inversor multinível modular baseado na conexão série para o acionamento de motores com enrolamentos em aberto".

Área de Conhecimento: Eletrônica de Potência e Acionamento Elétrico

Banca Examinadora:

Prof. Ivo Barbi, Dr. -- Orientador -- UFSC;

Prof. José Renes Pinheiro, Dr. -- UFSM;

Prof. Samir Ahmad Mussa, Dr. -- UFSC;

Prof. Telles Brunelli Lazzarin, Dr. - UFSC;

Eng. Gierri Waltrich, Dr. -- Pós-Doutorado -- UFSC e

Prof. Roberto Francisco Coelho, Dr. -- Suplente -- UFSC

Moderador:

Prof. Clóvis Antônio Petry, Dr. -- UFSC

domingo, 3 de novembro de 2013

MODELAGEM E PROJETO DE FILTROS HÍBRIDOS DE POTÊNCIA: CONTRIBUIÇÕES À ANÁLISE DE DESEMPENHO EM REDES COM DISTORÇÕES TIAGO DAVI CURI BUSARELLO

TIAGO DAVI CURI BUSARELLO
MODELAGEM E PROJETO DE FILTROS HÍBRIDOS DE
POTÊNCIA: CONTRIBUIÇÕES À ANÁLISE DE
DESEMPENHO EM REDES COM DISTORÇÕES
CAMPINAS
2013
Dissertação de Mestrado apresentada ao Programa de Pós-Graduação
em Engenharia Elétrica da Faculdade de Engenharia Elétrica e de Computação da Universidade
Estadual de Campinas para obtenção do título de Mestre em Engenharia Elétrica.
Área de concentração: Energia Elétrica.
DOWNLOAD LINK
http://www.mediafire.com/?v2n2s53oc3jhaxv