Estimation of mechanical transients in ’’tuned-circuit’’ levitators by employing steady-state impedances

Investigations of a relatively new magnetic levitation device are described. This device uses an electromagnet, which is the inductive part of a resonant circuit. If the circuit is properly tuned, static stability is attainable. ’’Tuned-circuit’’ levitators are characterized by typical transients of the suspended object which are difficult to analyze. The work described here is a contribution towards simplifying the calculations of such transients. The analysis presented in the paper relies on calculating the impedance of the tuned circuit for each position of the suspended object. Though the impedance obtained in this way is merely the ’’steady-state’’ impedance of the circuit, it enables one to predict some of the parameters characterizing the mechanical transients of the suspended object. The frequency of mechanical oscillations is the main parameter to be predicted in this way. Investigations were conducted where the predicted mechanical frequency of oscillations was compared with that obtained experimentally. The results of the experiments were usually close to those expected by theory.