on load tap changers

[angelina sirri]

Hello matpower users,
I would be interested in implementing on load tap changers in an opf 
calculation. I searched in the archive but I couldn't find a clear help. How to 
change the tap in the transformer of the slack bus? Is it a change done in the 
mpc file or should I modify runopf code? Any instructions and clarifications 
would be valuable!
Kind Regards,Angelina