Effect of spring non-linearity on dynamic stability of a controlled maglev vehicle and its guideway system

The non-linear effect of a spring on the dynamic characteristics of a magnetically levitated (or maglev) vehicle and its guideway system is numerically studied in this paper. A simplified theoretical model of a maglev vehicle with heavy and forward motions on flexible guideways is suggested to study the coupling among the motions of vehicle, the vibration of guideways, and the control system of the electromagnetic suspension. The stable regions and/or the attracting regions of the attractor of the controlled system either with a non-linear spring or with a linear spring are obtained. It is found that the stable region is strongly dependent upon the non-linear terms of the spring, the forward velocity of the vehicle, and the control parameters. Finally, the chaotic response of the system with a non-linear spring is presented.