Control of magnetic levitation positioning stage with an eddy current damper

To enhance the system damping, a permanent magnet set which served as an eddy current damper was added to the magnetic levitation positioning stage which consists of a moving table, four Halbach permanent magnetic arrays, four stators and displacement sensors. The dynamics model of this stage was a complex nonlinear, strong coupling system which made the control strategy to be a focus research. The nonlinear controller of the system was proposed based on the theory of differential geometry. Both simulation and experimental results show that either the decoupling control of the movement can be realized in horizontal and vertical directions, and the control performance was improved by the damper, verifying the validity and efficiency of this method.