Influence of Guideway Surface Roughness on a Magnetically Levitated Vehicle with Mechanical Levitation Control. 4th Report. Influence of Nonlinear Characteristics of Magnet.

Abstract

This paper describes the influence of the nonlinear characteristics of a magnet, which is expected to have a large influence on levitation performance of a maglev vehicle with mechanical air gap control. The effect of nonlinear characteristics of magnets on levitation performance, which is expressed by the guide wheel load of the vehicle, is initially analyzed from a static point of view. Numerical calculation and experiments using test vehicle are carried out to show nonlinear effect of the magnet on the levitation performance. The dynamic levitation performances are analyzed by a simulation study with 3 DOF and 17 DOF vehicle models. The simulation results show that the unstable rolling motion of the undercarriage is caused by nonlinear characteristics of magnets if a low control lever ratio is set. It is also shown that the deterioration of levitation performance caused by nonlinear characteristics of magnets is suppressed by a large control lever ratio.