Real Time Digital Control of Magnetic Bearings with Microprocessors

This paper presents the work on the real time implementation of digital controllers applied to magnetic bearings to levitate high speed rotor systems. Microprocessor is employed for digital signal processing. The control loop consists of PID controller, tracking and fixed notch filters, lead compensators, and feedforward stage, etc. The controller is implemented with TI TMS320C67 processor incorporated with LabVIEW data acquisition and graphical user interface. Digital signal processing techniques including bilinear transformation, frequency pre-warping, digital filter design and I/O communications are applied to implement the control rule. The real time controller has been successfully applied to the levitations of a revolver test rig in Vibration Control Lab at Texas A&M and the energy storage flywheel system used by industries for vehicles