Decoupling Control of Bearingless Induction Motor Based on Rotor Flux Orientation with Inverse System Theory

A bearingless induction motor is a multi-variable, strong-coupled and nonlinear system. To start with, according to the working principles of bearingless induction motor, the equations of torque force and radial suspension forces are inferred. Then the state equations of motor based on rotor flux orientation is set up. Secondly, the reversibility of system based on the mechanical equations is discussed in detail. Using ¿-th order inverse system, dynamic decoupling control between radial force and electromagnetic torque force and radial forces are realized. Finally, the controllers are designed respectively according to the linear system theory. The simulation results have showed that the whole control system has good dynamic and static performance.