Now i see the diode is ok and thank you for getting nit picky on the 400 uF cap.
The last problem i have is the 360 vdc peaks. A friend of mine in body work used to say "you can't fill a high spot down" and that is what we have, a high peak of about 30 volts we can not get rid of because we can only add voltage.
The ripple calculation says 28 to 33 v and it looks like that is what we need to get rid of to meet out 330 vdc spec. Adding more DC voltage to the 360 vdc peak supply will only make things worse. So i do not see how it is regulating unless they do not mind the ripple voltage and only want to boost up the 360 vdc supply if the 208 vac line sags.
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208ph-ph x Sqrt(2) = 294V peak, thus the other psu must add up to 36V or more to get 330VDC regulated
The schematic clearly shows a 3 phase connection and 3 phase bridge.
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You can not believe how hard it was to find an authoritative source for 3 phase Y to full bridge and DC.
https://en.wikipedia.org/wiki/Rectifier#Three-phase_bridge_rectifier
For a three-phase full-wave diode rectifier, the ideal, no-load average output voltage is
Vdc = 3 x (sq root of 3) x V peak / pi
Vpeak, the peak value of the phase (line to neutral) input voltages.
208v line to neutral = 120 vac x 1.414 = 170 v peak
3 x 1.732 x 170 V peak / pi = 281 vdc
So you were correct, the inverter must add voltage to meet the 330 vdc spec, and this would fill in the ripple.
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Last thought, under the inverter bridge it says 10.7v at 10A. I kept looking all along for the 10.7 volts to be significant but i do not see any relevance. Does anyone else see why this was posted?