Dynamic Response Prediction and Track Component Installation Deviation Limit Study for 600 km/h EMS Maglev Vehicle Based on Track Irregularity Theoretical Model

Track irregularity is one of the primary excitations for the electromagnetic suspension (EMS) high-speed maglev transportation system, which affects the levitation stability and ride comfort. Developing a track irregularity theoretical model that incorporates track structural parameters, and applying it into vehicle–track system dynamic simulation, is crucial for exploring the dynamic boundaries and conducting the optimizing design. This study proposes a track irregularity samples model based on the characteristic length and stochastic feature. The spectrum functions of height, alignment, cross level, and gauge irregularities along the track centerline can be obtained to form the track irregularity theoretical model (TITM), and the long-wavelength component is added into this TITM. This proposed TITM is validated against measured data and then applied into maglev vehicle–track coupled dynamics simulation. The simulation is conducted to predict the dynamics responses at operation speed of 600 km/h and to explore the influence law of the key parameters on the vehicle–track coupled system dynamics responses. When the high-speed maglev vehicle is operating at speed of 600 km/h, the maximum fluctuation of the levitation gap and guidance gap may reach to 5.83 and 4.97 mm, indicating a potential risk of electromagnet-rail collision. The vertical and lateral Sperling index values are 2.98 and 2.81, respectively, which means they only belong to the qualified level. When the installation deviation of stator extends to 1.6 mm, the levitation electromagnet acceleration amplitude value may increase about 15%. And with the installation deviation of the guidance plane extending to 2.2 mm, the amplitude value of the guidance electromagnet increases about 20%. The stiffness and damping value of the air spring are suggested to be set as 190 kN/m and 4,000 Ns/m. This study can support forward for track–vehicle matching design at operation speed of 600 km/h and also can provide an analyzing method for exploring the control system ability boundaries and the limitations of track irregularities.