Design And Implementation Of Magnetic Bearing System Controller Based On H_∞ Theory

This paper is the research on the mathematic model of the Active Magnetic Bearings , caculates the mechanical parameters of the model and analyses the effect of peg-top coupling and inertial coupling. It probes into the selection of weighting function matrixes based on the mixable sensibility of H_∞ control for linear time-invariant(LTI) system and its restrict conditions and principles. Besides, it applys the structre of 3-bolck to avoid singularity problem and restrain the high gain of frequency. Using the LMI in MATLAB optimizes the paraters of H_∞ controller. By combining the performance and needs of Active Magnetic Bearings , the H_∞ controller which satisfies the stability and robustness is obtained. The final experiment results meet the requst of system performance , and verify theapplicability and effectiveness of this design method .The H_∞ control of magnetic bearing is realized by applying real-timediscretization and digital controller , which is a control program and runs in computer control system based on PCI card . The final experiment results meet the requst of system performance , and realize the AMB experiment suspending under 30000r/min which verified the applicability and effectiveness of this design method .