Decoupling and levitation control of a six-degree-of-freedom magnetically levitated stage with moving coils based on commutation of coil array

Abstract

The research in the present paper focuses on decoupling the six-degrees-of-freedom motions of a magnetically levitated stage with moving coils and controlling the levitation motion. The decoupling is based on commutation of coil array, which is obtained reversely from the electromagnetic force/torque model of the stage. The control of levitation motion is carried out by a phase lead-lag controller designed on the criterion of minimum integral of time-weighted absolute error after gravity compensation modeling of the plant dynamics. Comprehensive simulations of the control system in MATLAB/Simulink and real levitation experiments on a digital signal processor-centered test platform are made to verify the six-degrees-of-freedom decoupling effect and the closed-loop control performances of the levitation degree of freedom. The results indicate that the six-degrees-of-freedom motions of the stage can be decoupled through coil array commutation and the levitation motion can be controlled by the phase lead-lag controller based on the gravity compensation model and designed on the criterion of minimum integral of time-weighted absolute error.