Vibration control for active magnetic bearing high-speed flywheel rotor system with modal separation and velocity estimation strategy

The active magnetic bearing (AMB) high-speed flywheel rotor system is a multivariable, nonlinear, and strongly coupled system with significant gyroscopic effect, which puts a strain on its stability and control performances. It is very difficult for traditional decentralized controllers, such as proportional-derivative controller (PD controller), to deal with such complex system. In order to improve the stability, control performances and robustness against noise of the AMB high-speed flywheel rotor system, a new control strategy was proposed based on the mathematical model of the AMB high-speed flywheel rotor system in this paper. The proposed control strategy includes two key subsystems: the modal separation subsystem, which allows direct control over the rotor rigid modes, and the velocity estimation controller, which improves the robustness against noise. Integration of modeling results into the final controller was also described. Its ability and effectiveness to control the AMB high-speed flywheel rotor system was investigated by simulations and experiments. The results show that proposed control strategy can separately regulate the stiffness and the damping of conical mode and parallel mode of the AMB high-speed flywheel rotor system, and obviously improve the stability, dynamic behaviors and robustness against noise of the AMB high-speed flywheel rotor system in the high rotating speed region.