0-30v 5a power supply schematic
I think N2 current regulator and N1 voltage regulator. But i didn't understand the feedback loop of N1 and how the transistor V26A is working. V26A emitter is open circuited at DC, it can be wrong shematic.
It is very complex design and not suitable for bench supply for hobbiest. a 2x15V/1A simple linear regulator with short circuit protection will be ok. You can make it by using LM723 type regulators with output voltage range between 1-20V easily.
Regards