Okay, this got me as well.
I took the little computers next to me and made sure I was to the point on the edge where if I took one step that I would fall off.
I force-gripped a computer and moved it (not throwing it) as far towards the generator as possible. When it couldn't move anymore, I threw it at the generator. It may take two or three tries, but it works- trust me.
The game probably suggests throwing a TIE Fighter- rubbish. You can grip one, but by the time you move it into position, it might break apart or get smashed to pieces- plus, it's too large to throw accurately.