Abstract: A gain schedule robust controller with a low order is introduced. It can restrain the nutation of the rotor in a large speed range without increasing the high-frequency gain of the controller and guarantee the robust performance of the system. The nutation damping comes from a phase jump caused by a zero-pole pair and the high-frequency gain of the controller decreases with a low-pass filter inserted. With the controller parameters changing on line according to the rotational speed, the gain schedule of the controller is achieved and the robust performance of the system is verified by μ analysis method. Simulation results show that the low order gain schedule robust control method can restrain the nutation in the whole speed range and it is easy to be used.

Key words: Active magnetic bearing, Flywheel, Gain schedule, Gyroscopic effects