Advanced numerical analysis for vibration characteristics and ride comfort of ultra-high-speed maglev train

Abstract

Magnetic levitation (maglev) trains are environmentally-friendly, require little maintenance, and allow for mass transportation. For these reasons, the demand for ultra-high-speed maglev trains has been increasing. Maglev trains can be classified with two suspension types, electro dynamic suspension (EDS) and electromagnetic suspension (EMS). EDS-type trains are suitable for ultra-high-speed because levitation suspension gap is over 100 mm compared with levitation suspension gap of 10 mm for EMS. When speed goes faster, it is hard to control the small suspension gap rapidly in EMS type. To analyze the EDS-type maglev train, electromagnetic forces were calculated with the superconducting coils and magnets using 2D analytical model. Based on the calculated forces, the lookup tables for the levitation and guidance force were employed in the total couple-fielded analysis. Ultra-high-speed maglev train was simulated by using the ADAMS multi-body dynamic program. The simulation was carried out with two car body models, rigid and flexible car body. In order to construct flexible car bodies with the modal information, the finite element method was used and they were constructed with the equivalent elements using ANSYS (TM). The final framework was constructed in MATLAB Simulink, and we co-simulated the dynamics and the electromagnetics with the constructed simulation frame work. To consider disturbances caused by irregularities, random and power spectral density (PSD) were used to analyze the vibrational interaction. As results, the ride comforts for PSD were a little bit worse than the results for random irregularity because the characteristics of PSD irregularity have more low excitation frequencies. The use of PSD inputs and flexible car body models need to be considered to improve the simulation accuracy.