Buying a new playstation 3?

May be...

I am going to move to Europe and I wanna get a new ps3 but if I do. Do I lose all my trophics and my online ranks

Nope, when you get your PS3 just log onto your PSN account and they should all be there.

I think you'll not lose any, because it is stored online...

not if u keep the same online sign in name