Design of linear auto disturbance rejection controller for magnetic bearing of high-speed motors

Magnetic bearings can not only solve the life problems of bearing wear and but also reduce the loss and noise of bearings. However, the strong non-linear and uncertainty of parameter of the magnetic bearings make the traditional PID controller difficult to ensure its long-term and stable operation. In this paper, the nonlinear model of magnetic bearing was built by means of the field-circuit coupling analysis, then the method of linear auto disturbance rejection control(LADRC) for magnetic bearings was presented. The simulation results of magnetic bearing for a high speed motor show that the proposed control method has better performance compared with the traditional PID control method.