well if you are going to wind the transformer like that then I obviously agree with all your points. I thought if the original poster was as clumbsy and non-dexterous as I am, then they will want an easier time winding a transformer and so would pick a full bridge instead…and just put up with the 4 fets and two bootstrap drivers. I agree the output inductor peak to peak current wont be affected if you wind for the low leakage like that. It sounds like you are doing mulitple layer interleaving, with 4 secondaries interleaving. At least the OP knows they should keenly watch for the leakage if they do pick the pushpull.
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As you know to get low leakage in a transformer wind, its also good if you can get the layers over the full width of the bobbin with windings evenly spaced across the bobbin. So I hope the OP looks out for this aswell.
Sometimes if I only need a small number of turns for a particular coil, then I find they wouldn’t spread across the full bobbin width if not “spiralled”, and so I put windings in parallel and ask for them to be “flat wound” (so as not to use up the bobbin depth)…this way the few windings can nicely fill right across the bobbin width….but then the transformer manufacturers get back and tell that they can’t terminate the multiple turns to a single pin……….or they say that such “flat winding” is expensive.
I hope the OP knows that spec’ing “spiral” winding, with a few number of turns evenly spaced across the bobbin, is risky, because as we found, the winders often don’t bother doing it…they just clump the turns at one end of the bobbin width………peeling back the transformer after manufacture reveals this.
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I am sure the OP knows that if they do pick the full bridge, they do also have to be mindful of the leakage inductance, because as you know, in CCM, the primary current initially slopes up at a di/dt of Vin/Llk….and so with large amounts of leakage inductance, the duty cycle D will have to be that little bit higher.
I still wonder that the OP may find that the easiest of all transformer winds will come if they cheat and shovel a cascaded booster in there first, then with the much increased new vin, they can achieve the vout with the isolated stage with greater ease…..they will have much less current in the primary…and not such a high turns ratio to deal with.