Danfoss VLT AHF005 Design Manual

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Danfoss VLT AHF005 Design Manual Manual pdf 14 page image

0 20 40 60 80 1000510152025 THvD 0%THvD 2%THvD 5%Load [%]THiD average [%]130BB580.10Illustration 4.1 AHF00501020304050600 20 40 60 80 100Load [%]THvD 0%THvD 2%THvD 5%THiD [%]130BB581.10Illustration 4.2 AHF010Performance at 10% THvD has not been plotted. However,the filters have been tested and can operate at 10% THvDbut the filter performance can no longer be guaranteed.The filter performance also deteriorates with the unbalanceof the supply. Typical performance is shown in the graphsbelow.0% unbalance1% unbalance2% unbalance3% unbalance0 20 40 60 80 100Load [%]02468101214THiD [%]130BB582.10Illustration 4.3 AHF005130BB583.1000 20 40 60 80 100Load [%]510152025 0% unbalance1% unbalance2% unbalance3% unbalanceTHiD average [%]Illustration 4.4 AHF0104.1.1 Power FactorIn no load conditions (the frequency converter is in stand-by)the frequency converter current is negligible and the maincurrent drawn from the grid is the current through thecapacitors in the harmonic filter. Therefore the power factoris close to 0, capacitive. The capacitive current is approxi-mately 25% of the filter nominal current (depends on filtersize, typical values between 20 and 25%). The power factorincreases with the load. Because of the higher value of themain inductor L0 in the AHF005, the power factor is slightlyhigher than in the AHF010.Following graphs show typical values for the true powerfactor on AHF010 and AHF005.00,10,20,30,40,50,60,70,80,910 20 40 60 80 100Load [%]True Power Factor130BB584.10Illustration 4.5 AHF0050,10,20,30,40,50,60,70,80,910 20 40 60 80 100Load [%]0True Power Factor130BB585.10Illustration 4.6 AHF010Introduction to Advanced Ha... AHF005/010 Design GuideMG.80.C4.02 - VLT® is a registered Danfoss trademark 134 4