High Speed Magnetic Bearing Turbine
Magnetic bearings are increasingly becoming popular in industrial and manufacturing applications due to their ability to suspend high-speed rotating loads with no friction and operate under environmental constraints which prevent the use of lubrication. Magnetic bearings are now employed to provide control system technology for the design of implantable artificial hearts. The Magnetic Bearing here at Clemson University is one obtained from Magnetic Moments. With the Turbo 500 Option, the magnetic bearing rotor can go up to a speed of 10,000 RPM and with high-speed version of the Turbo 500, speeds of upto 25,000 RPM can be reached.
Research Focus :
Nonlinear Control Applications
The ability to actively control magnetic bearings further enhances its scope of operation and offers numerous advantages over conventional bearings. The internal control system for the bearings provides for imbalance compensation and rotor damping via the electromagnets. In a typical magnetic bearing application, however, like a machine tool spindle, the magnetic forces, which are applied by sets of stator electromagnets, must be adjusted online to ensure that the rotor is accurately positioned. The control problem is complicated due to the inherent non-linearities associated with the electromechanical dynamics introduced into the magnetic bearing system due to the spindle that it drives. Many of the previous magnetic bearing control techniques are based on the linearized electromechanical model. In the last couple of years, the integrator backstepping (IB) control technique has received much attention since it provides the framework for attacking many electromechanical control problems similar to magnetic bearing applications. One of the main advantages of the IB family of control design tools is the proviso for systematic, desirable modifications of the control structure such as compensation for parametric uncertainity or eliminating state measurements.