Current Feedback Stabilization of Tuned Magnetic Suspension System

Suspension techniques employing a tuned LC circuit have the advantage that stable suspension can be achieved without using independent displacement sensors. Therefore, they are suitable for levitating micro mechanical objects by either magnetic or electrostatic force. However, tuned LC circuit suspension systems suffer from inherent dynamic instability, which has seriously hampered the research and applications of this technique. In this paper, a current feedback stabilizition method is proposed, and its effectiveness is confirmed experimentally.