Coupled vehicle-guideway dynamics simulations of the Transrapid with discretized levitation magnet forces

Abstract

Magnetic levitation (maglev) is a promising technology for high-speed transportation systems, as shown by the Transrapid line in Shanghai operating successfully for nearly 20 years. Currently, a new high-speed train based on this technology is being developed, driven by China's Ministry of Science and Technology. Magnets are one of the key components of a maglev vehicle's suspension system. Attractive magnet forces ensure the contactless coupling of the vehicle to the guideway. Electromagnets are usually described using finite element (FE) models, electromagnetic circuit models, or simple analytical models for simulation purposes. However, FE magnet models are computationally often overwhelming, especially for transient studies, and thus too slow to use them in large vehicle models for vehicle dynamics simulations. Moreover, the parameterization of FE models often is non-trivial. Therefore, less detailed but fast-computable models are used in such simulations, often providing only a coarse discrete distribution of magnet forces along the vehicle. In this contribution, the coupled vehicle-guideway dynamics is investigated regarding different discretizations of levitation magnet forces. A two-dimensional model of the maglev vehicle Transrapid moving along an infinite elastic guideway is used, considering the heave-pitch motion of the vehicle and the vertical guideway bending. Simulations are performed using either a coarse distribution with two magnet forces per magnet or a fine distribution with twelve magnet forces per magnet, i.e., one magnet force at each magnet pole. It is shown that the simplification of two magnet forces per levitation magnet is valid for vehicle dynamics simulations. The model is parameterized with data from the Transrapid TR08 and uses a self-developed model predictive control (MPC) scheme to control the magnets.