This is a paranoid "what if" question.

What if one of your competitors dislikes you enough that they decided to go through all of your adsense ads and click each one repeatedly, over an extended period of time, for the explicit purpose of getting you banned. :eek:

Does Google have detection systems for stuff like this? And if so, what is the appeals process to get reinstated?
(Its sort of the opposite of unscrupulous webmasters doing this to boost their earnings.)

They should be able to see that the clicks were coming from one IP address and you should see the same thing in your log files.
They could take your account offline while they investigate - but it is more they do not have the ability to ban the abuser as they do to stop what it is they are abusing.