Vibration transmission analysis of high-speed maglev vehicle under low-speed experimental conditions

Abstract

The 600 km/h high-speed maglev transportation system represents the fastest existing ground transportation technology. As the electromagnetic suspension (EMS) type high-speed maglev system currently lacks the conditions for full-speed testing, this study conducted low-speed dynamic experiments to investigate the vibration transmission characteristics within the vehicle system. First, time-domain track irregularity data were derived from the low-speed experimental data. Subsequently, time-frequency analysis was performed on the dynamic responses at different vehicle locations, and the coherence between track irregularities and these responses was investigated. Finally, the vibration transmission characteristics were analyzed using the vibration acceleration level difference method. The results indicate that the energy of the measured track irregularities is concentrated within the low-frequency range below 15 Hz. Within the 0∼13.67 Hz low-frequency range, track irregularities constitute the primary influencing factor on the vehicle’s dynamic responses. The vibration reduction performance of the primary suspension is relatively weak. In contrast, the flexible levitation frame and air spring exhibit frequency-dependent vibration reduction effectiveness across different bands, while the bolster, hanger rod, and auxiliary floor demonstrate effective vibration isolation and reduction performance across the entire frequency range. These findings provide support for the optimization of suspension systems in high-speed maglev vehicles.