Decoupling control of the 5 degree-of-freedom bearingless induction motor based on α-th order inverse system method

A decoupling control approach based on alpha α-th inverse system has been developed for the innovative 5 degree-of-freedom bearingless induction motor, which is multi-variable, nonlinear and high coupling system. To start with, the working principles of innovative 5 degree-of-freedom bearingless induction motor is briefly introduced. Then the mechanical equations of 3 degree-of-freedom magnetic bearing and 2 degree-of-freedom bearingless induction motor are given. Also the state equations of the motor are set up. Secondly, the reversibility of system based on the mechanical equations is discussed. Using alpha α-th inverse system, the control between radial force and electromagnetic torque force and radial forces control are decoupled. Last but not least, 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.