China's Energy Sector | GCEP Symposium 2010

 September 28, 2010 - As part of the Global Climate and Energy Project's 6th Annual Research Symposium at Stanford University, Xu Kuangdi, Honorary Chairman of the Governing Board of the Chinese Academy of Engineering and former Mayor of Shanghai, discusses recent changes and rapid development in China's energy generation and distribution industries.

Stanford University:
http://www.stanford.edu/

Global Climate and Energy Project:
http://gcep.stanford.edu

Precourt Institute for Energy:
http://pie.stanford.edu

Stanford University Channel on YouTube:
http://www.youtube.com/stanford

Einstein's General Theory of Relativity | Lecture 7

Lecture 7 of Leonard Susskind's Modern Physics concentrating on General Relativity. Recorded November 3, 2008 at Stanford University. This Stanford Continuing Studies course is the fourth of a six-quarter sequence of classes exploring the essential theoretical foundations of modern physics. The topics covered in this course focus on classical mechanics. Leonard Susskind is the Felix Bloch Professor of Physics at Stanford University. Stanford Continuing Studies: http://continuingstudies.stanford.edu/ About Leonard Susskind: http://www.stanford.edu/dept/physics/people/faculty/susskind_leonard.html Stanford University Channel on YouTube: http://www.youtube.com/stanford

COMPENSAÇÃO ATIVA PARALELA BASEADA NA TEORIA DE POTÊNCIA CONSERVATIVA

COMPENSAÇÃO ATIVA PARALELA BASEADA NA
TEORIA DE POTÊNCIA CONSERVATIVA
H. K. M. Paredes D. I. Brandão E. V. Liberado F. P. Marafão
Unesp - Univ Estadual Paulista, Grupo de Automação e Sistemas Integráveis - GASI
Av. Três de Março, 511, Sorocaba, SP, Brazil, 18087-180
hmorales@sorocaba.unesp.br; daniloiglesiasb@yahoo.com.br; eduardo.verri.liberado@gmail.com;
fmarafao@sorocaba.unesp.br
Resumo – Com o objetivo de avaliar a aplicação da
Teoria de Potência Conservativa (CPT, do inglês
Conservative Power Theory), para o controle de filtros
ativos de potência, este artigo apresenta uma metodologia
seletiva para a geração de sinais de referência de filtros
ativos paralelos, a qual é baseada na decomposição das
correntes medidas, conforme proposto pela CPT. A
decomposição ortogonal das correntes resulta em várias
componentes, cada qual associada com uma
característica específica da carga (transferência de
potência, armazenamento de energia, deslocamento de
fase entre tensão e corrente, desbalanço e/ou não
linearidades). Desta forma, cada componente pode ser
escolhida de forma independente (ou em associação),
proporcionando assim uma compensação seletiva dos
distúrbios de corrente oriundos do comportamento da
carga. Com o intuito de validar a metodologia proposta,
um filtro ativo trifásico foi simulado e avaliado
experimentalmente em um sistema trifásico de 4
condutores, com cargas desbalanceadas e não lineares.
LINK
http://www.mediafire.com/?t29woaso30d9a6e

Modern Transformerless Uninterruptable Power Supply (UPS) Systems

Modern Transformerless Uninterruptable Power Supply (UPS) Systems brahim Güne 1, Bülent Üstüntepe2, and Ahmet M. Hava3 1,2 ENEL Energy Electronics Company, 34794 Istanbul TURKEY igunes@enel.com.tr, bustuntepe@enel.com.tr 3 Department of Electrical and Electronics Engineering, Middle East Technical University, Ankara, TURKEY hava@metu.edu.tr Abstract Uninterruptable power supplies (UPS) are widely used to supply critical loads and provide reliable and high quality energy to the load. Until recently, on-line UPS systems with isolation transformer have been widely employed. However, transformerless modern UPS systems have been rapidly replacing the old technology due to their superior performance and size attributes. Transformerless UPS systems have utility friendly input performance and high quality output voltage waveform. Furthermore, smaller size, higher efficiency, and increased reliability are features that spread the transformerless products, rendering the transformer technology obsolete. In this paper, modern transformerless UPS systems with the 6-300kVA range will be discussed and their experimental performance will be illustrated. Input and output power quality performances, energy efficiency performance, and size/weight information will be provided on modern commercial transformerless UPS products.
LINK
http://www.mediafire.com/?2bfg3nxgr2t239x

Inovação no Desenvolvimento Integrado de Produtos ENG. PAULO TADEU DE MELLO USP PARTE2

Inovação no Desenvolvimento Integrado de Produtos ENG. PAULO TADEU DE MELLO USP PARTE2 from armando cavero on Vimeo.