Hello,
I have been workingon a PSFB converter for a while and I skipped to secondary side desgining. the secondary side will be synchronus and it is center tapped transformer. The voltage on mosfets drain source is max. 150V in topology and the RMS current is max. 40A so I need to pick a mosfet with very low Rdson like 10mohm-15mhom and I found a mosfet with 200V max and low Rdson. Is it safe to use this mosfet with this 200V voltag level ? If no , Can a RC snubber circuit damp voltage spike effectively ? and Can Iuse 200V mosfet with RC snubber ?

 

I dont see enough of the circuit to even guess about an answer. Seriously.

 

It is design phase yet , here is the whole scheme . It is basically PSFB DC-DC converter and center tapped secondary.

 

The effectiveness of any snubber depends on the ratio of impedances between the snubber's and the transient's source impedance. That impedance value is often not much better than guessed at. But since part of the circuit between the source and the device protected can be seen, a good minimum estimate can be made, allowing selection of an adequate snubber value.