| Tweeker |
If I were to use a 6 pulse bridge rectifier with a choke input LC filter, relative to the AC RMS voltage across each secondary, what DC voltage out would I get:
With delta connected secondaries?
With wye connected secondaries? |
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| poobah |
Tweeker,
The ralationship between delta and wye is the square root of 3 (1.73). So if you measure 120 volts from leg to neutral (wye); you will measure 208 volts from leg to leg (delta... or wye for that matter). |
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| Tweeker |
I know 3 phase wye bridge rectified without a choke but capacitor gives 2.45*VAC RMS= VDC, what does it give with a choke? 1.73*.9= 1.56?
With delta connected secondaries, does this mean output with choke would be VAC RMS * .9 = VDC?
What scant information I can find seems to indicate this isnt quite right, choke input polyphase rectifiers seem to be obsolete. |
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| poobah |
I will have to look... in a little red book I have...
Wait for tomorrow... I can't promise an answer... I just don't want to give you a BS one.
:xeye: :D |
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| Tweeker |
| In fact Im pretty sure it isnt * .9, average voltage would be much higher than with single phase. |
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| poobah |
hey Tweeker,
The average voltage factor is 0.954969. I couldn't find my little red book so I Armstrong-ed it in Excel... PM me if you want the spreadsheet.
Remeber, when you sum the 3 rectified phases the voltages don't add... they merely overlap... only the biggest voltage wins...
OH... this isn't RMS... multply by 1.414
:D |
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