Det bliver interessant:
https://www.littleboxchallenge.com/#details
Krav:
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* Must be able to handle up to 2 kVA loads
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* Will be taking in 450 V DC power in series with a 10 Ω 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%
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* Must have a DC-AC efficiency of greater than 95%
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Så den skal have ægte sinusformet output – ikke opklippede firkanter.
Aug 1, 2006, Modified Sine-Wave Inverter Enhanced:
http://powerelectronics.com/power_systems/…
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There are basically two kinds of dc-ac inverters on the market today. One category is the “pure sine-wave” inverter, which produces sine waves with total harmonic distortion (THD) in the range of 3% (-30 dB). These are typically used when there is a need for clean, near-sine-wave outputs for medical, instrument and other critical applications…These inverters are available in sizes up to several thousand watts and typical costs are in the range of $0.50 per watt
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The second category consists of relatively inexpensive units, producing modified sine-wave outputs, which could logically be called “modified square waves” instead. They are basically square waves with some dead spots between positive and negative half-cycles …Their costs are generally in the range of $0.10 per watt
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Løsningen er her 
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En ny måde at lave sinus fra DC er her:
“Magic sinewaves” – teori fra ca. år 2000. Don Lancaster, Synergetics og 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 flankeskift. Det er også virkeliggjort med 3 fasede vekselrettere. Kan anvendes til elbiler og AC elektromotorstyring incl. BLDC:
Magic Sinewaves: An Executive Summary:
http://www.enginuitysystems.com/files/msin…
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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.
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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”.
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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…
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“Magic sinewaves” are repeating long sequences of ones and zeros. 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 en inverter modulationsteori som er exceptionel – det påstås at den specielle timing af flankerne gør at alle harmoniske op til ca. 22. harmoniske af 50 eller 60 Hz.
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Jul 1, 2008 Inverter Design Shines in Photovoltaic Systems | Renewable Energy Applications:
http://powerelectronics.com/power_systems/…
http://powerelectronics.com/site-files/pow…
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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.
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Jun. 19, 2013, SiC MOSFETs Enable Next-Generation Solar Inverters:
http://powerelectronics.com/products/sic-m…
29kr
SiCFET N-Channel, Silicon Carbide
1200V (1.2kV)
10A (Tc)
585 mOhm @ 3A, 18V[gs]
Reverse transfer capacitance 4pF [!]
http://www.digikey.dk/product-detail/en/SC…
Datablad:
http://rohmfs.rohm.com/en/products/databoo…
49kr
SiCFET N-Channel, Silicon Carbide
1200V (1.2kV)
17.7A (Tc)
196 mOhm @ 10A, 20V[gs]
Reverse transfer capacitance 4pF [!]
http://www.digikey.dk/product-detail/en/C2…
http://www.cree.com/~/media/Files/Cree/Pow…
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Der findes også SiC-dioder:
80kr
DIODE SCHOTTKY 1.2KV 36A TO247
No Recovery Time > 500mA (Io) [!]
http://www.digikey.dk/product-detail/en/AP…
http://www.microsemi.com/document-portal/d…
Her er en 1,7kV SiC-diode:
371kr
DIODE SCHOTT 1.7KV 26.3A TO247-2
No Recovery Time > 500mA (Io) [!]
http://www.digikey.dk/product-detail/en/C3…
http://www.cree.com/~/media/Files/Cree/Pow…
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