Abstract
This paper investigates the modelling of one-degree-of-freedom magnetically levitated system considering both the PI control characteristics of power amplifier and delay characteristic of magnetic flux density in the electromagnet is performed. Especially, the directional characteristic of the general power amplifier is considered in the modelling. Then, the nonlinear resonance phenomena and bifurcation phenomena in this model are studied. The numerical simulation and the theoretical results show good agreement. Theoretical results clarify the influences of dynamical parameters of the magnetically levitated system on the nonlinear vibration phenomena in detail. Furthermore, the performed experiment validates the obtained theoretical results.
