Concept of a laboratory power source 0-50V 350W?

I'm thinking about designing a laboratory resource.
Basic requirements

Output voltage 0-50V
Output current 0-25A
Output power 350W max
Precise voltage, current and power regulation
Possibility of serial and parallel merging more PS.

My first concept.
1.a stage 350W PFC PFS7528H
1.b 230 to 53V 7A LLC with LCS705HG 250kHz
1.c 230 to +-12V, +5V,+12V with TinySwitch-4 for for supplying the power source electronics
2. Synchronous Buck Controller 53 to 0-50V m,ax current 25A with LM5145
3. Maybe linear stage with NPN transistor for precise linear regulation .
All drive with high speed MCU any as STM32F3

What do you say about it, is it a good conception?
Ideal would be to skip the stage 2, but I do not know if 1b stage handled a voltage of 5 to 53V 7A with one transformer winding.

Is this a product or a hobby?

1c will have a lot of other options such as non-isolated buck modules drawing from the 53. Perhaps one 53->12 and then +5/-12 from that. That could be all off-the-shelf and will save you a transformer.
https://www.digikey.com/product-detail/en/recom-power/R-78HB12-0.5/945-1057-ND/2256237

Yes I was staring at 1.c and 2. LLC is a nice efficient soft switching topology but can't varry it's output very much. Half bridge or zvs full bridge in particular (which I'm familiar with) can easily vary from 0-50V in one stage. But to maintain 25A you will pay for this in the transformer sizing (have you looked at planar?). The benefit of your current topology with the final buck is that it 'makes current' on the secondary.

Another option are Vicor bus converter modules which can handle the PFC->Isolated 48V (unregulated) and would blow away anything you might do in terms of size:
https://www.vicorpower.com/dc-dc/isolated-fixed-ratio/hv-bus-converter-module

If this is one of a kind supply, I also agree that it is best to purchase a ready made front end and you focus on the rest of the circuit. Which should be challenging enough.

But of course, if your purpose is t learn, you may design and build everything yourself.

Thank you for the types.
about using full bridge I thought for a while, I liked it STM32F334 and full digital H bridge controll.
Unfortunately, ST also manufactures a full-bridge power source demo board controlled by these MCUs, but it falsely conceals and prevents access to firmware. And I dare not design both magnetic circuits while writing firmware from zero.
For similar reasons I prefer IC from Power Int. They have their IC software for designing and calculating the transformer and other elements of the power source.

TI has a couple phase shifted full bridge (ZVS) demo's using their digital DSP line and provides all the source code.
https://www.ti.com/tool/TIDA-00412

Though microchip also pushes their solutions but in my experience I've seen many more reference designs built around TI compared to anyone else.

We got a couple TI demo boards in consideration of using them for a phase shifted full bridge but couldn't get comfortable with the design tools fast enough to pull the trigger on it (I'm currently doing converter/amplifier control in FPGA's, which I'm comfortable with, but DSP's would be a cost savings for some of what we do).

In terms of its hardware capabilities its the way to go over analog in many cases. But DSP design is no small task. Just learning the tools alone is a substantial learning curve.

asrock70 said:

power 350W max
...
Possibility of serial and parallel merging more PS.

Click to expand...

Your desired Watt amount could be in the form of:

15V 24A,
30V 12A,
or 60V 6A.

It would be efficient to purchase 4 transformers, 15V 6A.
Switch the secondaries so they can be arranged all in parallel, or all in series, or 2 strings of 2 ea.

And it's a convenient path to obtain bipolar split supplies, because it's like having a 0V center tap:
+12 -12V @12A
+30 -30V @6A

You may need to build more than one section to rectify/ filter/ regulate the different configurations.

Your job could be made easier if you were to use a variac (2A @ 230 VAC). I purchased a 2A 120V type for a few dollars on Ebay years ago.