Endelig: En offentlig elektronik konkurre nce med et højt mål

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26. jul 2014, Google vil give en million dollar til opfinderen af en  
lille vekselretter.


http://ing.dk/artikel/google-vil-give-en-million-dollar-til-opfinderen-af-en-lille-vekselretter-169740


Det bliver interessant:
https://www.littleboxchallenge.com/#details
Nogle af kravene:
Citat: "...
* Must be able to handle up to 2 kVA loads
...
* Must be in a rectangular metal enclosure of no more than 40 in^3
...
* Will be taking in 450 V DC power in series with a 10 ? resistor
* Must output 240 V, 60 Hz AC single phase power
* Must have a total harmonic distortion + noise on both voltage and  
current of < 5%
...
* Must have a DC-AC efficiency of greater than 95%
..."


Mon Google vil anvende dem til at drive deres PCere via solceller?

Glenn

Re: Endelig: En offentlig elektronik konkurrence med et højt mål
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snakkede om at springe ensretter og ladelyt og power factor dims over, og  





--  
Ulrik Smed
Aarhus



Re: Endelig: En offentlig elektronik konk urrence med et h?jt m?l
On 26/07/14 20.46, Ulrik Smed wrote:
...




...

Der allerede lavet innovation i denne retning - det er blot ikke bredt  
kendt:




adskillige Synergetics Partnere har lavet en inverter modulationsteori,  
som er eksceptionel. F.eks. kan alle harmoniske op til ca. 22.  
harmoniske af 50 eller 60 Hz udfases via et specielt timing-design af  

anvendes til elbiler og AC elektromotorstyring incl. BLDC:

Magic Sinewaves: An Executive Summary:
http://www.enginuitysystems.com/files/msinexec%20%28Magic%20Sinewaves%29.pdf
Citat: "...
Proper system design will require low pass filtering of these higher  
order harmonics. Compared to other digital sinewave generation methods,  
these unwanted harmonics are quite high in frequency and thus should be  
fairly easy to deal with. As before, real world quantization will  
increase the zero intermediate odd harmonics to finite but acceptably  
low real values.
...
Until some recent considerable serendipity requiring exceptionally  
tedious brute force methods ( involving over a decade of research ),  
there was not the slightest hint that any solutions at all existed for  
the above equations. Let alone ones highly useful for power quality and  
energy efficiency. Hence the believed uniqueness and originality of the  
Magic Sinewave approach. I presently believe that no closed form method  
of solving the above equations is currently known. Nor is any likely to  
even exist. Instead, an iterative standard tool related to Newton?s  
Method can be used. One that otherwise is crudely known as "shake the box".
...
A group of highly sophisticated JavaScript Magic Sinewave calculators  
are now available and have been posted to
http://www.tinaja.com/magsn01.asp
[ nu: http://www.tinaja.com/magsn01.shtml ]
With solutions presently offered as high as 384 zeroed low harmonics.

A solution set for the above equations would be...
..."

"Magic sinewaves" are repeating long sequences of ones and zeros. [i  
retning af PWM] They can get created from ordinary but extremely  
carefully chosen digitally switched pulses. Se f.eks.:
http://www.tinaja.com/magsn01.shtml

Introduction to Magic Sinewaves (pdf):
http://www.tinaja.com/glib/msintro1.pdf

Three Phase Magic Sinewaves (pdf):
http://www.tinaja.com/glib/deltams1.pdf

Magic Sinewave Demo Hardware! (pdf):
http://www.tinaja.com/glib/mschips.pdf

Steplocked Magic Sinewave Synthesis (pdf):
http://www.tinaja.com/glib/stepsynt.pdf

Don Lancaster', Synergetics og adskillige Synergetics Partnere har lavet  


harmoniske af 50 eller 60 Hz.

-

Jul 1, 2008 Inverter Design Shines in Photovoltaic Systems | Renewable  
Energy Applications:
http://powerelectronics.com/power_systems/electric_utility_grid-connected_photovoltaic_system/
http://powerelectronics.com/site-files/powerelectronics.com/files/archive/powerelectronics.com/power_systems/807PET21-inverter-design-photovoltaic-systems.pdf
Citat: "...
A proposed photovoltaic current-source grid- connected inverter has  
small volume, low total harmonic distortion, high power factor and  
simple control, and also simplifies photovoltaic system design.
..."

Jun. 19, 2013, SiC MOSFETs Enable Next-Generation Solar Inverters:
http://powerelectronics.com/products/sic-mosfets-enable-next-generation-solar-inverters

Glenn


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