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”

sábado, 10 de dezembro de 2016

Transformer Shielding Technique for Common Mode Noise Reduction in Switch Mode Power Supplies Yuchen Yang -Virginia Polytechnic Institute and State University









Transformer Shielding Technique for Common Mode Noise Reduction in Switch Mode Power Supplies Yuchen Yang
 Thesis submitted to the Faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering.

(Abstract)
 Switch mode power supplies are widely used in different applications. High efficiency and high power density are two driving forces for power supply systems. However, high dv/dt and di/dt in switch mode power supplies will cause severe EMI noise issue. In a typical front-end converter, the EMI filter usually occupies 1/3 to 1/4 volume of total converter. Hence, reducing the EMI noise of power converter can help reduce the volume of EMI filter and improving the total power density of the converter. For off-line switch mode power supplies, DM noise is dominated by PFC converter. CM noise is a more complicated issue. It is contributed by both PFC converter and DC/DC converter. While many researches have focused on reducing CM noise for PFC converter, the CM noise of DC/DC converter still remains a challenge. The main objective of this thesis is provide a solution to have best CM noise reduction for DC/DC converters. The shielding concept and balance concept are combined to propose a novel balance double shielding technique. This method can have an effective CM noise reduction in the circuit level. In addition it is easy to design and implement in the real production. The balance condition is easily controlled and guarantees effective CM noise reduction in mass production. Then, a novel one-layer shielding method for PCB winding. transformer is provided. This shielding technique can block CM noise from primary side and also cancel the CM noise from secondary side. In addition, shielding does not increase the loss of converter too much. Furthermore, this shielding technique can be applied to matrix transformer structure. For matrix transformer LLC converter, the inter-winding capacitor is very large and will cause severe CM noise problem. By adding shielding layer, CM noise has been greatly reduced. In addition, by modifying the secondary winding, the loss on shielding layer is minimized and experiments show that the total efficiency of converter has almost no impact. Furthermore, although this thesis uses flyback and LLC resonant converter as example to demonstrate the concept, the novel shielding technique can also be applied to other topologies that have similar transformer structure.

 LINK ORIGINAL WEB
https://vtechworks.lib.vt.edu/bitstream/handle/10919/49263/Yang_Y_T_2014.pdf?sequence=1

sexta-feira, 9 de dezembro de 2016

High Frequency-Link Cycloconverters for Medium Voltage Grid Connection -Shattock, Nicholas -PhD thesis, University of Nottingham.





High Frequency-Link Cycloconverters for Medium Voltage Grid Connection Nicholas Shattock BEng. (Hons) Thesis submitted to the University of Nottingham for the degree of Doctor of Philosophy 

Abstract
 As the deployment of renewable generation increases in the worldwide electrical grids, the development of distributed energy storage becomes more and more of an essential requirement. Energy storage devices connected at Medium Voltage allows for much higher powered deployments and this Ph.D. will focus on the power converter used to interface the energy storage device to the electrical grid. Multi-level converters can be used to provide this interface without huge ltering requirements or the need of a Low Frequency step up transformer. However traditional Multi-level converter topologies require a large number of electrolytic capacitors, reducing the reliability and increasing the cost. Multi-level converters constructed from a Cycloconverter Topology do not require any additional electrolytic capacitors, however the High Frequency transformer, used to provide isolation has to be considerably larger. This Ph.D. will investigate a novel hybrid converter topology to provide an interface between an energy storage device, such as a super-capacitor or battery, to the Medium Voltage grid, designed for high reliability and power density. This topology is called The Hybrid Cycloconverter Topology and is based on a Cycloconverter Topology connected to an auxiliary 3-Phase VSI. A comprehensive simulation study is carried out to investigate the semiconductor losses of this novel converter topology and compared against two alternative topologies. An experimental converter is constructed to validate the theory of operation and to justify its e ectiveness.

 LINK ORIGINAL
http://eprints.nottingham.ac.uk/14205/1/index2.pdf
LINK ALTERNATIVO
http://www.mediafire.com/file/yeyc074pn02azbq/High_Frequency-Link_Cycloconverters.pdf

sábado, 3 de dezembro de 2016

Communication Circuits: Analysis and Design by Kenneth K. Clarke




Communication Circuits: Analysis and Design by Kenneth K. Clarke ESTUDIE CIRCUITOS ELECTRONICOS III CON ESTE LIBRO EN LA FACULTAD DE INGENIERIA ELECTRÓNICA DE LA UNIVERSIDAD NACIONAL MAYOR DE SAN MARCOS SIENDO MI PROFESOR EL ILUSTRE PROF. Carlos Sanchez Tarnawiecki hoy Profesor del Postgrado at Universidad Nacional Mayor de San Marcos

LINK ORIGINAL EN LA WEB
http://www.samanezehn.com/ketab2.pdf
LINK ALTERNATIVO
http://www.mediafire.com/file/a937ig695iiah4a/communication_circuits.pdf

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