When you register a ps3 copy, you tie your psn with the SE account you register for. You can have multiple on the same account but I recommend you use a different psn account as it separates them nicely. When you register your new copy on the ps3 link the copy to your already existing SE account so you can play your character.

Myself and my wife play on the ps3, the only thing you need to worry about is buying a new copy of the ps3 version and ensure you register it on your SE account and not create a new one.