Research On Dynamics And Lightweight For Levitation Chassis Of Long Stator Middle-Low Speed Maglev Vehicle

As a safe and comfortable, green, less noisy and pollutive traffic mode, magnetic levita-tion vehicles has become the important modern symbol of the human ground passenger transport. Furthermore, the middle-low speed maglev vehiele with the advantage of low noise, low power, good line adaptability and low cost, has become a new competitive public transport on the interior of city.The levitation chassis is one important part of mgalev train with complex working con-ditions. It is the carrying platform of the maglev train, but also the working platform of traction and steering. Its attributes also affect the dynamic performance and structural relia-bility of the whole tarin directly. It is neeessary to Research the dynamic characteristics of levitation chassis. At the same time, the suspension mode of maglev train is the electro-magnetic levitation, and maglev train has the stringent requirements on its own weight. In order to increase the load and improve the reliability of train operation, there is important significance to do the structural optimization job on the basis of its structure finite element analysis. Based on the long stator middle and low speed maglev vehicle of Southwest Jiao-tong University, the dissertation carried out the research on modeling, simulation and lightweight analysis of levitation chassis system dynamics, the detailed research works and main results were as follows.(1) Based on bouncing, pitching and rolling directions of vibration, the vertical dynam-ics model of levitation chassis was established, and the equations of motion of the model were derived. A simulation program using a Newmark explicit integration method was de-signed to simulate the vibration dynamic characteristics. The influences of suspension pa-rameters which were different stiffness and damping values and line irregularity frequency changed on the dynamic characteristics of levitation chassis were studied. Therefore the rea-sonable value interval of suspension parameter was explored.(2) The steady-state response characteristics of the long stator middle-low speed maglev levitation chassis were obtained on the basis of its supposed design data. The results showed that the dynamic characteristics of levitation chassis have good performance. At the same time, the influence of elastic suspension constraints between the left and right module when the structure decoupled was studied. It provided a reference for the optimization of an-ti-rolling suspension parameters on the levitation chassis. (3) With the assembly entity SolidWorks model of the long stator low-speed maglev train levitation chassis and the ANSYS Workbench analysis software, the static perfor-mances of levitation chassis under the four working conditions of maglev vehicle were ana-lyzed, and the modal analysis and harmonic analysis of levitation chassis were studied based on the most dangerous condition. The analysis results showed that the stiffness and strength of levitation chassis met the load requirements of maglev vehicle, and the vibration frequen-cies were in a safe range.(4) Based on the sensitivity analysis, the reasonable design variables of levitation chas-sis were determined and the optimization mathematical model was established aim to have the minimum weight of levitation chassis. On the premise of guaranting strength, stiffness and vibration frequency, the lightweight design of levitation chassis was achieved.In conclusion, the theoretical analysis and simulation studies on the vertical dynamics and lightweight design of the long stator middle-low speed maglev levitation chassis were obtained. The results have reference values for structural improvements of levitation chassis and selection of suspension parameters, besides it is of great significance to improve riding quality and reliability of maglev vehicle.