FB-LLC or PSFB for converter with variable load (up to 1.5kW) ?

Thread Starter


Joined Mar 4, 2022
I was wondering if FB-LLC (FullBridge LLC) or PSFB (Phase Shift FullBridge) is a better suited topology for a up 1.5kW converter (DC-bus 400V to DC-out 100V). The important part is that it should work over a wide load range (10W to 1.5W).
For my understanding is there the PSFB a better choice, but it radiates more EMI. The FB-LLC, which has lower EMI, is more complicated to develop for a wide load range. Based on what I've read I would say that the efficiency is about equal, when having a wide load range.
I'd like to note that GaN based transistors are intended to be used for this project in order to reduce the losses during switching.

I'd like to hear your comments regarding the better choice.

I've already tried to evaluate the differences between those two topologies, on my own: