H_∞ control and simulation for magnetic bearing of reaction flywheel

An H_∞ controller based on sensitivity function was designed after the system analyzing and model building on magnetic bearing of reaction flywheel which has an external rotor, a large moment and a small span. The S-T characteristic simulation curve and step response simulation curve of PID and H_∞ controller were given also. The results indicate that the H_∞ controller can provide more robustness, higher control accuracy and higher ability of disturbance limiting than PID controller.