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”

https://picasion.com/
https://picasion.com/

segunda-feira, 19 de setembro de 2016

High-Efficiency Three-Phase Current Source Rectifier Using SiC Devices and Delta-Type Topology Ben Guo University of Tennessee





High-Efficiency Three-Phase Current Source Rectifier Using SiC Devices and Delta-Type Topology 
A Dissertation Presented for the Doctor of Philosophy 
Degree The University of Tennessee, Knoxville
High-Efficiency Three-Phase Current
Source Rectifier Using SiC Devices and
Delta-Type Topology
A Dissertation Presented for the
Doctor of Philosophy
Degree
The University of Tennessee, Knoxville
Ben Guo

December 2014
Abstract 
In this dissertation, the benefits of the three-phase current source rectifier (CSR) in high power rectifier, data center power supply and dc fast charger for electric vehicles (EV) will be evaluated, and new techniques will be proposed to increase the power efficiency of CSRs. A new topology, referred as Delta-type Current Source Rectifier (DCSR), is proposed and implemented to reduce the conduction loss by up to 20%. By connecting the three legs in a delta type on ac input side, the dc-link current in DCSR can be shared by two legs at the same time. To increase the switching speed and power density, all-SiC power modules are built and implemented for CSRs. The switching waveforms in the commutation are measured and studied based on double pulse test. Four different modulation schemes are compared for high efficiency CSR considering the switching characteristics of different device combinations. The most advantageous modulation scheme is then identified for each of the device combinations investigated. A compensation method is proposed to reduce the input current distortion caused by overlap time and slow transition in CSRs. The proposed method first minimizes the overlap time and then compensates the charge gain/loss according to the sampled voltage and current. It is verified that the proposed method can reduce the input current distortion especially when the line-to-line voltage is close to zero. The dc-link current will become discontinuous under light load in CSRs, when the traditional control algorithm may not work consistently well. To operate CSR in discontinuous current mode (DCM), the CSR is modeled in DCM and a new control algorithm with feedforward compensation is proposed and verified through experiments.
LINK ORIGINAL  WEB
http://trace.tennessee.edu/cgi/viewcontent.cgi?article=4357&context=utk_graddiss

ADVANCE THREE PHASE POWER FACTOR CORRECTION SCHEMES FOR UTILITY INTERFACE OF POWER ELECTRONIC SYSTEMS A Thesis by MESAAD WALEED ALBADER -Texas A&M University



ADVANCE THREE PHASE POWER FACTOR CORRECTION SCHEMES FOR UTILITY INTERFACE OF POWER ELECTRONIC SYSTEMS A Thesis by MESAAD WALEED ALBADER Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE

Chair of Committee, Prasad Enjeti
Co-Chair of Committee, Hamid Toliyat
Committee Members, Shankar P. Bhattacharyya
Won-Jong Kim
Head of Department, Chanan Singh
August 2014
ABSTRACT
 Modern power electronic systems operate with different voltage and/or frequency rating such as Adjustable speed drive, Micro Grid, Uninterruptable Power Supplies (UPS) and High Voltage DC Transmission Systems. To match power electronic systems with the mains supply, DC link converters are used. The first stage of the DC link converter is the AC/DC conversion (rectifier). The rectifier type utility interface has substantial harmonics result in poor power quality due to low power factor and high harmonic distortion. Power Factor Correction (PFC) schemes are effective methods to mitigate harmonics and address this issue. In this thesis, analyses of three approaches for high power density rectifiers are developed. In the first study, modular three phase boost rectifiers operating in DCM are coupled in order to increase the power density. Major drawback of this rectifier is the high currents ripple in both the source and the DC link sides which require large EMI filter size -could be larger than the rectifier component size- and large DC filter capacitor size. This thesis proposes coupling modular three phase boost DCM rectifiers, the currents in both source and DC link sides are interleaved and consequently the currents ripple dramatically decreased results in small component size of the EMI filter and the DC filter capacitor leading to high power density rectification. Also, optimization of the number of the rectifier modules to achieve maximum power density is presented. Moreover, the switching function of each rectifier employs harmonic injection technique to reduce the low order harmonics. And, the DC output voltage is varied with the load power such that the operation is at the boundary between CCM and DCM to achieve maximum power density tracking.
 LINK ORIGINAL THESIS
http://oaktrust.library.tamu.edu/bitstream/handle/1969.1/153331/ALBADER-THESIS-2014.pdf?sequence=1

Eric Giler: A demo of wireless electricity


Eric Giler: A demo of wireless electricity
LINK https://www.ted.com/talks/eric_giler_demos_wireless_electricity

TESLA Wireless Power Transmitter and the Tunguska Explosion of 1908 -Беспроволочная технология передачи энергии Н.Тесла и Тунгусский взрыв




Nikola Tesla and Tunguska On June 30, 1908, over 100 years ago, a huge explosion destroyed over 1,000 miles of a very remote and sparsely inhabited region of central Siberia. The exact date of the event is very uncertain because nobody from the outside reached the region until 1927, and there is an 11 day difference between the Julian calendar then used by the Russians, and the Gregorian calendar which supplanted the Julian calendar. In 1582, Pope Gregory XIII massacred the calendar by taking out 11 days in the month of October. The Russians did not convert to the Gregorian calendar until after the 1917 Russian Revolution. About June 30,1908, a huge explosion completely devastated a 2,600 square kilometer area of Siberia. This explosion was 1,000 times more powerful than the Hiroshima atomic bomb, and larger than the devastation caused by subsequent nuclear bomb testing by the U.S. and Russia. Because of the remote location, the Russian Revolution, and Civil War, an expedition did not reach Tunguska until 1927. Initial reports said that it was a meteorite because a celestial phenomenon like the northern lights or aurora borealis could be seen as far south as London. This explosion was not a meteorite or visitors from outer space....It was the work of the super Serbian scientist named Nikola Tesla.
 SOURCE ORIGINAL
http://www.reformation.org/tesla-and-tunguska.html

Circuit Theory I


Lecture Notes

WeekLectureNotes
Week 1Circuit Theory I: goals and underlaying assumptions
Week 2Circuit Variables
Week 3Circuit Elements
Week 4Resistive Circuits
Week 5Circuit Analysis Techniques and Theorems
Week 6Operational Amplifier
Week 7Operational Amplifier Imperfections
Week 8Energy Storage Elements and transformers
Week 9First order RC and RL circuits
Examples of Sequential Switching Circuits
Week 10RLC circuits: part a   part b
Anant Agarwaland Jeffrey Lang, course materials for 6.002 Circuits and Electronics, Spring 2007. MIT OpenCourseWare(http://ocw.mit.edu/), Massachusetts Institute of Technology.
Downloaded on [2 Dec 2009]

LINK ORIGINAL EN LA WEB
https://www.blogger.com/blogger.g?blogID=1078288880652113587#editor/target=post;postID=2934418545071209264