Advice needed to achieve better stability.

[RATAN ROY]

Hi,
I need to make a DC power supply of ratting 170A,100V with ppm less than 100.It would be 12 pulse thyristor based with microcontroller driven.But i m not getting bettre ppm.what should i consider or what precaution should i take including power components and wirings

 

[dick_freebird]

What "ppm" are you after? Load regulation, line, temperature, all together?

Load reg wants a remote sense (ground and voltage).
Line probably wants high-PSRR error amplifier and reference
elements, perhaps pre-regulation. Temperature is all about
the reference.