The output voltage is 10V at 500A(?)
The PSFB’s have a vin of ~400V.
So three PSFB’s (one from each phase path), with 10V output, each deliver about 165A.
I think the transformer needed to do this wouldn’t be from an offtheshelf standard type. This transformer, the core and bobbin, would need to be custom made…which is doable, but costly.
Also, I think you would have to look at custom flat conductors for this transformer…specially made and costly. What are your predicted sales volumes?
For how long at a time is this converter on full power?