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”

sexta-feira, 2 de dezembro de 2016

Quasi Z-Source AC-AC converter system connected in series With Dynamic Voltage Restorer(DVR) capability Jun-Hyun Eom - Department of Electrical Engineering Graduate, School Chonnam National University-SOUTH KOREA


동적전압보상 기능을 갖는 출력이 직렬 결합된 Quasi Z-소스 AC-AC 컨버터
 Quasi Z-Source AC-AC converter system connected in series With Dynamic Voltage Restorer(DVR) capability Jun-Hyun Eom
 Department of Electrical Engineering Graduate, School Chonnam National University (Supervised by Professor Young-Cheol Lim)

(Abstract)
 Recently, different with the conventional load, the present load devices such as computers, Automated production equipments, precision electronic devices are very sensitive to the power quality. These load devices sensitive to the power quality are increasing sharply and people are paying more and more attention to the AC-AC power conversion devices like instantaneous voltage-compensators, phase-shifters, electronic transformer which are installed in the side of power system or consumers. Similarly, the AC chopper, PWM AC-AC converter, matrix converter and Z-Source AC-AC converter also belong to the AC-AC power conversion devices referred above. among these devices, due to the latest research method, the Z-Source AC-AC converter has quite simply structure and control method and is possible to boost output voltage in phase and boost or buck output voltage out of phase with respect to input voltage.

Nevertheless, since the Z-Source AC-AC converter operates in DCM (Discontinuous Current Mode), stress of the elements is bigger compared with the case of CCM(Continuous Current Mode) and it's very disadvantageous viewed from the waveform. It is probable to solve the problems referred above by Quasi Z-Source AC-AC converter. However, the operation of buck mode is impossible, even though it's possible to boost or buck the output voltage out of phase and boost the output voltage in phase.

In this study, a single-phase quasi Z-source AC-AC converters with a series connection of the output terminals is proposed. The proposed system has configuration that the input terminals of two quasi Z-source AC-AC converters are connected in parallel and its output terminals are connected in series. for output of in-phase buck mode with respect to the input ,the intersection switching control is presented and the current flow in both of the out phase mode and in phase mode and the output voltage's forming process was shown.

In addition, a DVR(Dynamic Voltage Restorer) though using a single-phase quasi Z-source AC-AC converter connected with the output terminals in series is proposed. In general, among the problems which cause the lower quality, the Voltage Swell or Voltage Sag could be the major one which brings great influence to the consumers with high frequency and sensitive load. The Voltage Swell which is the increasement of the supply voltage's magnitude in duration of 0.5∼30[cycles] while the voltage magnitude is 1.1∼1.8[p.u] of nominal voltage and the Voltage Sag which is the drop of the supply voltage's magnitude in duration of 0.5∼30[cycles] while the voltage magnitude is 1.1∼1.8[p.u] of nominal voltage can lead to the accidents happening in most of the nearby distribution circuits. Such Voltage Swell or Voltage Sag causes the misoperation or suspension of work and bring about Nevertheless, since the Z-Source AC-AC converter operates in DCM (Discontinuous Current Mode), stress of the elements is bigger compared with the case of CCM(Continuous Current Mode) and it's very disadvantageous viewed from the waveform.

It is probable to solve the problems referred above by Quasi Z-Source AC-AC converter. However, the operation of buck mode is impossible, even though it's possible to boost or buck the output voltage out of phase and boost the output voltage in phase.
In this study, a single-phase quasi Z-source AC-AC converters with a series connection of the output terminals is proposed.

LINK ORIGINAL EN LA WEB
http://ocean.kisti.re.kr/downfile/volume/kipe/JRJJC3/2013/v18n4/JRJJC3_2013_v18n4_322.pdf


terça-feira, 29 de novembro de 2016

AMORPHOUS METAL CORES IN MEDIUM FREQUENCY POWER TRANSFORMER - Morteza Razaz Department of Electronic and Electrical Engineering University of Salford - England



AMORPHOUS METAL CORES IN MEDIUM FREQUENCY POWER TRANSFORMER
 Thesis submitted to the University of Salford for the degree of Doctor of Philosophy by Morteza Razaz Department of Electronic and Electrical Engineering University of Salford Salford M5 4WT England

 LINK
http://usir.salford.ac.uk/14782/1/308481.pdf

segunda-feira, 28 de novembro de 2016

The Design of LLC Resonant Converter for Wireless Power Transfer Inverter-- Seong-JinLim Department of Electrical Engineering Graduate School of Mokpo National University







대전력용 차단기 내의 EMC Filter 개발에 관한 연구 = A Study on Development of EMC Filter in the High Power Breaker -Graduate School of Korea Maritime University





Abstract 
 Recently, as the number of usage of various electronic devices increases rapidly, the demand for the power is also growing very much Therefore, to supply electricity of high quality steadily and minimize the power loss, the voltage of power transmission and distribution is getting higher and higher to the maximum, and the demand for heavy electric machines such as high power transformer, instrument transformer, and breaker, is also increasing[I]. The heavy electric machines includes all of machines and tools to transfer the electricity generated from the power plants to houses or factories. It must be insulated well in the high voltage, and do its functions properly even in the extreme working conditions. Therefore, in this dissertation, the EMC filter in the high power breaker, one of the heavy electric machine, was suggested as a countermeasure for conductive noises. And the suggested EMC filter in the high power breaker was attenuated 25 - 70 dB in the range of 10 MHz 1.5 GHz When the EFT of 4 kV in the level 4 of IEC 61000-4-4 was induced, it was soon suppressed to 600 V, and the filter was also verified its excellence by satisfying the level 4 of IEC 61000-4-4. Hence, the best feature of it was to prevent the leakage of electromagnetic noise by enhancing immunity of houses or factory machines. Go forward the suggested EMC filter can be applicable not even for electronic • information devices, but also electronic • control devices as the very innovative countermeasu- re, namely, the range of its application can be expected very broad.

sexta-feira, 25 de novembro de 2016

New Software Package for Teaching and Learning the Basics of Photovoltaic System Sizing - SEBASTIEN JACQUES, SEBASTIEN BISSEY University of Tours (France) Polytech Tours, Electronics and Energy Department



Abstract: This paper describes an innovative and highly modular software tool named PVLab and developed by the GREMAN laboratory in collaboration with Polytech Tours from the University of Tours (France). This simulation package assists the designer in the sizing of PV (photovoltaic) installations. PVLab has a high level of flexibility, allowing its physical models and databases (e.g., meteorological data) to be modified according to the user’s needs. This is made possible through the use of expertise applied to all of the computing steps, and to the MATLAB development environment. The user’s ability to control the source code itself will allow much greater progress to be made in the field of renewable energy applications than with PVsyst, which is currently the commercial reference. All of these features come together to make PVLab the perfect tool for modernizing higher education, in particular with regard to students’ competencies. Since recent years, the higher education landscape has been undergoing considerable change as a result of technological innovations and new pedagogical approaches [1], [2], [3]. The Bologna Declaration and Lisbon Strategy in Europe are the clearest examples of international commitment to reform and modernization of university education [4], [5]. The degree and qualifications obtained, in terms of workload, level and learning outcomes are major pillars of the Bologna Process [6]. The competency-based management has been developed to increase the readability and comparability of European higher education degrees worldwide [7], [8]. This approach also supports the employability of higher education graduates [9]. Indeed, they are expected to be fully operational in an international context upon completion of their studies. About 100 Engineering Schools in France have already started the process at the moment. This movement should speed up with the Engineering Education Commission (CTI) guidelines. The Polytechnic Engineering School of the University of Tours (Polytech Tours, France) has just initiated the continuous skills development. The Electronics engineers to design and to have an in-depth understanding of electronic systems, has recently set up new pedagogical tools to achieve the education system modernization target. With regard to the education of photovoltaic (PV) applications in particular, recent researches have focused attention on students’ investment to give them the methods, tools, skills, and understanding since they could potentially be involved in the design, sizing, and installation of PV systems within an efficient industrial context [10], [11]. As the use of photovoltaics expands, with more and more commercial and residential users investing on solar energy systems around the globe, there is a growing demand for software that can be used for the design, simulation, data analysis, and troubleshooting of PV systems, from the preliminary assessment of energy efficiency and cost-effectiveness to the development of the project documentation. For many years, PVsyst has been accepted as a reference by architects, engineers, teachers and researchers, especially as a result of its easy-to-use, and accuracy of electrical energy production estimation thanks to its extensive PV- component, and meteorological databases [12]. However, using this kind of software package, it is not possible to modify the electrical, optical and thermal models, nor the internal databases (i.e., PV modules, inverters, and meteorological databases) [13]. A major question is whether existing commercial PV software, such as PVsyst, are sufficient to accurate forecast the efficiency of a PV plant taking into consideration all technical and environmental requirements.

LINK ORIGINAL
http://www.wseas.org/multimedia/journals/education/2015/a245810-157.pdf

terça-feira, 22 de novembro de 2016

ICS ENGENHARIA ESPECIALISTAS EM PROTEÇÃO CONTRA INCÊNDIO


A ICS Engenharia é um grupo de empresas de projetos e serviços com experiência de mais de 35 anos na área de Engenharia de Proteção contra Incêndio. Especialista e experiente no segmento de proteção contra incêndio soma casos de sucesso no atendimento aos seus clientes. Em constante crescimento, atualmente separou suas equipes em dois segmentos para atender com excelência a cada demanda:
PROJETOS e SERVIÇOS PROJETOS
 • Proteção contra incêndio
 • CFTV
 • Controle de Acesso
 SERVIÇOS
 • Gerenciamento de obras
 • Manutenção dos equipamentos contra incêndio
 • Assistência Técnica
 • Automação industrial
 • Instalação de sistemas de proteção contra incêndio

WEBSITE :http://icsengenharia.com.br/

 CONTATO Av. Luiz José Sereno, 1.257 Jd. Ermida II – Jundiaí – SP – 
13212-210 55 11 4805-5501 qualidade@icsengenharia.com.br

TELEFONE (11) 4805-5501


segunda-feira, 21 de novembro de 2016

ANALYSIS OF AN INTEGRATED PFC INDUCTOR AND RESONANT TRANSFORMER BASED ON MAGNETIC MODELING - MEAS SARAN -Department of Electrical and Electronics Engineering Graduate School of Engineering Jeonju University Jeonju, Korea


ANALYSIS OF AN INTEGRATED PFC INDUCTOR AND RESONANT TRANSFORMER BASED ON MAGNETIC MODELING MEAS SARAN Advised by Prof. Kim, Eun Soo A thesis submitted to Jeonju University in partial fulfillment of the requirements for the degree of Master of Science Department of Electrical and Electronics Engineering Graduate School of Engineering Jeonju, University Feb 2013 ABSTRACT
This paper describes the design and analysis of an integrated transformer comprising of two different power cores- the PFC inductor and the LLC resonant transformer magnetic core. The equivalent magnetic circuit modeling approach is employed to analyze the variations in coupling coefficient and self-inductance in terms of air gaps under the operations of the respective power cores. Simulations and experimental studies were performed with the fabricated integrated transformer prototype and the results were discussed. In recent years, the demand for highly regulated and reliable power supplies with the desired smaller size, lighter weight and high efficiency in power electronics system has increased. The magnetic components are usually higher and heavier than other components on the circuit-boards. The answer for both miniaturization and material performance can be planar core technology. Therefore, the planar core was selected for 2-in-1 transformer design in this paper.
LINK ORIGINAL
http://ocean.kisti.re.kr/downfile/volume/kipe/JRJJC3/2015/v20n3/JRJJC3_2015_v20n3_262.pdf

sexta-feira, 18 de novembro de 2016

Integrated Magnetic Transformer for ZVS Phase Shift Full Bridge Converter -By Xinlan Li-GYEONGSANG NATIONAL UNVERSITY Department of Electrical Engineering


Integrated Magnetic Transformer for ZVS Phase Shift Full Bridge Converter A Dissertation submitted to the Faculty of the Graduate School of the Gyeongsang National University By Xinlan Li In partial fulfillment of the requirements for the degree of Master of Engineering July, 2008

 Abstract
 Integrated Magnetic Transformer for ZVS Phase Shift Full Bridge Converter Xinlan Li Department of Electrical Engineering Graduate School Gyeongsang National University Supervised by Professor Hwi-Beom Shin
 Integrated magnetic (IM) has been widely used in power electronics system. The design of IM transformer is considered in a zero voltage switching (ZVS) phase shifted full bridge converter. The purpose of this design is to improve the performances, like power density, packaging, size and cost of IM transformer that can be applied to high frequency converter.
 In this dissertation a new IM transformer is proposed. The transformer is located on the center leg; the output inductor is located on the outer legs with air gaps. The design equations and equivalent magnetic circuit are presented. The analysis of each timing interval is included for ZVS. For reducing the core size, EE core is redesigned. The applications of these circuit are verified on a 1.2kW prototype converter through experimental results. The performance of the proposed IM transformer is compared with conventional IM transformer.
 The efficiency of proposed IM is similar to the one of conventional IM but the size of proposed IM is reduced up to 20%. Therefore, with the proposed IM transformer, the power density can be largely increased. I. Introduction The IM transformers begin to be used in the low output voltage and high current power electronics system [1]. With the IM technique, two or more magnetic components are integrated in one magnetic structure. The EE or EI core is commonly utilized. The magnetic parts in the converter may be reduced, so that the size and power density can be improved. In some case, overall efficiency may be increased and an EMI problem may be reduced. For a PSFB converter, several IM transformers are proposed [2]. The transformer winding is typically located on the two outer legs in series connection and the inductor is wound on the center leg. The AC flux of transformer and a half of the DC flux of inductor flows in outer legs but the inductor flux only flows in the center leg. The flux density in outer legs is much higher than one in center leg because the center leg has nearly two time cross-sectional area of the outer leg. This IM transformer has a high magnetizing inductance. Since the transformer coupling is low, EMI may be high. A new IM transformer is proposed for ZVS PSFB converter in this paper. The transformer winding is located on the center leg for close magnetic coupling and the inductor is wound on two outer legs in series connection. The proposed IM transformer is analyzed electrically and magnetically. An E-core is redesigned and implemented.
 The proposed IM transformer is experimentally compared with the conventional one through a 1.2kW prototype ZVS PSFB converter and the performance is discussed.

II. ZVS PSFB converter and IM transformer
 ZVS PSFB converter is shown in Fig. 1. The center-tapped transformer
and the output inductor are usually integrated in one EE or EI core. Fig. 2(a) shows the proposed IM transformer and the circuit connection in the output stage. The transformer and output inductor are located on the center leg and two outer legs, respectively. The conventional IM transformer given in [2] is shown in Fig. 2(b).

2.1 Operation Principle 
When the PSFB converter operates in ZVS, there are 8 operating modes during each cycle as shown in Fig. 3. The ZVS transition intervals are magnified in Fig. 3 and these intervals can be neglected when analyzing the magnetic circuit. Hence, 4 modes only are considered for analysis. The duty ratio D is limited below 0.5 because of the alternating current. The magnetic states within each core leg are modeled by using the capacitive modeling method [3] ~ [5]. For simplicity, all the devices are assumed to be ideal. The permeance of core is assumed to be infinite. The operation is explained as follows.

quinta-feira, 17 de novembro de 2016

Gerente General de KOLFF en Matelec 2016


Eduardo Cordero Homad, Gerente General de KOLFF, estuvo presente en la reciente feria Matelec 2016 la cual se realizó este año en la ciudad de Madrid. Algunas de las actividades programadas tuvieron relación directa con la suscripción de acuerdos corporativos de colaboración con proveedores europeos de clase mundial. En KOLFF nos preocupamos continuamente de entregar los mejores productos y servicios a nuestros clientes, y es en esta línea que año a año generamos alianzas en pro de generar valor agregado al mercado latinoamericano.
LINK
http://kolff-e.com/2016/11/04/gerente-general-de-kolff-en-matelec-2016/