State feedback controller designs allow for pole placement in an effective manner, but reduction of static offset is difficult. On the other hand, classical control methodology allows for the increase of system type and the elimination of static offset. An integrally augmented state feedback controller provides the benefits of standard feedback designs while allowing for the elimination of static offsets (through the increase of system type). Static offset is a particular problem with magnetic bearing supported rotor systems, in that gravitational effects, current biasing, and operational loading tend to exacerbate this problem. In order to assess the effectiveness of this technique, an integrally augmented state feedback controller is developed, implemented, and tested for a magnetic bearing supported rotor system. Results for several selected configurations are presented and compared. Some conclusions and recommendations concerning the effectiveness of integrally augmented state feedback controller designs are presented.

Issue Section:
Gas Turbines: Structures and Dynamics
Keywords:
modelling, feedback, controllers, magnetic bearings, rotors, stability, vibrations, design for testability, mechanical engineering, gas turbines
Topics:
Control equipment, Design, Magnetic bearings, Rotors, State feedback, Feedback
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