ABSTRACT

Linear metro system is developed for urban transportation which is driven by linear induction motor (LIM). The vehicle mounted LIM interacts with the reaction plate (RP) fixed on the track system. A detailed model is built to analyze the vertical coupling vibrations characteristics of this system. The model consists of vehicle and track subsystem. The vehicle subsystem owns 10 DOFs. The track subsystem consists of three layers which are rail, track slab and rigid foundation. The track and the slab are both modeled by finite element method. The wheel/rail interaction is described by the Hertzian contact theory. The vertical attractive force between the LIM and its RP is modeled as special springs varied with the air gap. Dynamic simulation is carried out in Fortran program. Proper computing step has been determined through numerical test. The system dynamic characteristics and the air gap variations caused by the track irregularities have been studied.