I tend to agree with the poster who suggested you need two years of university-level math study to even begin to grasp the concepts used in controls engineering. However, you might be able to teach yourself the math using khanacademy.org before becoming a university student. You'll just need someone to point you in the right direction. Start with functions and with differential and integral calculi (two different subjects). This presumes you have already studied the math subjects prerequisite to calculus. If not, do that first.