If you kill a troll (or other monsters kill it like skeletons, but fat chance) you will trigger a raid event that you cant disable.

But there is a simple and stupid solution.
Araund your base dig down the ground all araund and trolls wont be able to reach you (they can still trow rocks).

Or just make a new world and move materials to that one as only raid that will spawn are pigs (till you kill a troll again).