This question has cropped up several times now and to date I have been stymied in finding the answer. Until I figured out a way to research this on another site and rip off someone else's answer. It is not exactly a movie you are thinking of, per se, which is why all of my previous searches have failed miserably. It's an Australian miniseries called
The Girl from Tomorrow, which aired in 1991. Parts of it were then edited into a movie in 1992, and a follow-up mini came along in 1993. Hoody hoo! I am the champion! Kneel before Zod!