On 26/07/14 20.46, Ulrik Smed wrote: ...
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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:
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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
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[ nu:
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] 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.:
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Introduction to Magic Sinewaves (pdf):
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Three Phase Magic Sinewaves (pdf):
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Magic Sinewave Demo Hardware! (pdf):
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Steplocked Magic Sinewave Synthesis (pdf):
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Don Lancaster', Synergetics og adskillige Synergetics Partnere har lavet
harmoniske af 50 eller 60 Hz.
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Jul 1, 2008 Inverter Design Shines in Photovoltaic Systems | Renewable Energy Applications:
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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:
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Glenn