Contactless Starting and Positioning of a Steel Ball in Single-Axis Magnetic Suspension Device by Variable Structure Control

The application of variable structure control has been proposed for a single-axis magnetic suspension device. The system enables a suspended body to move from a starting position located beyond a stable suspension region into an equilibrium point and control the position around the equilibrium point. Two variable controllers have been successfully applied;switching control from PD to I-PD and sliding mode control.