Adaptive compensation of sensor run-out and mass unbalance in magnetic bearing systems without changing rotor speed

摘要

The present invention provides a method and system for stabilizing a rotor about its geometric center in a magnetic bearing system at a constant rotor speed. In the method, the controller for controlling the magnetic bearing uses an adaptive control algorithm which simultaneously identifies and compensates for synchronous sensor runout and rotor mass unbalance while determining a control action that drives the rotor rotating at a constant speed to its geometric center. The identification of sensor runout and mass unbalance is by varying the magnetic stiffness which is achieved by perturbation of the bias currents in opposing electromagnet coils in a manner that does not alter the equilibrium of the rotor while it is rotating at a constant speed.