What model of cheap Chinese power supply would be a good choice?
I have a MLINK PPS3005 (programmable linear 30V 5A power supply).
exactly, this is some real good advice, starting analog for psu regulation and microprocessor for set U/I.
that kind of psu is also branded by Konrad if i remember well and it's one of my preferred approach, me personally i build another linear psu and another microprocessor control, but the main line linear regulation will teach op the basic mistakes ang goto's, the processor part to be elegant
tuning some dcdc already-made especially for big currents may not even be possible in the first place without major modification on feedback part, so i say no very loud. even experienced guy in electronics may smoke the psu in this scenario, usually those big amps psu's have a tight voltage regulation loop, you cannot make them from 0 to 24-30V easily without very good understanding, that's not for beginners
br, ovidiu