230VAC to 60VDC circuit

Question

I have a (750w) psu that takes up to 60vdc and would like to plug it in a 230vac 50Hz (domestic power outlet).

There are two solutions I thought of immediately, but am not sure which one is best :

1 : 230Vac -> transformer to 60Vac -> rectifier bridge -> bank of capacitor -> DCDC psu

2 : 230Vac -> rectifier bridge -> switching regulator -> bank of capacitor -> DCDC psu

1-> Rare and expensive transformer needed

2-> complex circuitry needed to switch the gate of a mosfet (to drop voltage down to 60vdc).

Of course the easiest would be to buy the converter but it's pretty difficult and the challenge could be interesting :)

(NB. I didn't take into calculation the rms, and other voltage drops for all of these values, the DCDC psu handles up to 50V 15A, I'd like to get the most out of it :) )

Answer 1

Ebay, telecom 'rectifier' unit, maybe the cost of a few beers, job done.

48-54V is a very standard bus voltage in the telecomms and server game, and you will be able to pick up a used suitable supply for not a lot of money. Of course you can design a 50V supply from scratch but at 750W it will cost you more then just buying a used one.

Note that your dc-dc unit is almost certainly intended to run from an isolated supply, so you will need a transformer in there somewhere, either big iron or a switch mode one.