This site:
http://www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=...
tells something about step load and step unload. It describes the methods of adjusting power supply when different capacitors are used to prevent overload and stress on parts of the machinery.

This site offers a bit more explanation:
http://www.pscexpo.com/2004/Papers/viewpapers.asp?papernum=0...


I'm sorry I can't help with an Italian translation, if that's what you were looking for, but these links might help you find new threads.

Just found this English/Italian pair: (search "step-down") on the English one, and I'm sure the Italian will make more sense to you than to me!! It's just a Google translation, but the company offered it on their English site!

http://www.warburtech.com/motion.control/icon.h-bridge/icon....

http://translate.google.com/translate?u=http://www.warburtec...