Research on one-dimensional motion control system and method of a magnetic levitation ball

Abstract

Research on the multi-degree-of-freedom and large-displacement motion control of the levitated object makes a contribution to broadening the application field of the Maglev technology. A one-dimensional motion control system and method of the Maglev ball are investigated in this paper. The Maglev ball motion control system is required to have a large operating range. In order to meet this requirement, a novel Maglev system based on double linear hall sensors is designed and implemented. The step-by-step control based on the Proportional-Integral-Derivative (PID) controller is proposed as one method to realize the large step response of the levitated object. The controlled object responds to the successive small step input rather than the large step input. Then, the mathematical model of the system is set up based on the electromagnetic force equation and controller parameters are tuned by following the mathematical model of the Maglev system at different positions. The experimental data show that the position accuracy of the Maglev control system using the PID controller reaches ±0.02 mm. Moreover, step-by-step control can not only safely realize large-displacement motion of the levitated object but also effectively reduce the overshoot of the step response and make the step response process smoother.