Design And Optimization Of The Low-speed Maglev Body Structure

Low-speed maglev trains have many advantages including riding comfortable, small turning radius, safety and don't worry about derailed, easy maintenance and environmental friendly etc, it is paid more and more attention. Yamanashi low-speed maglev train test line have been built in Japan and put in commercial operation. Engineering prototype vehicles have been manufactured respectively by Southwest Jiaotong University, National Defense University and Electrical Research Institute of Chinese Sciences Academy. They are promoting these research results into commercial applications positively. Beijing low-speed maglev line s1 has been constructed and put into trial operation in 2015.Low-speed maglev trains have its characteristics. Vehicles guiding, driving and braking systems are different from the existing wheel track vehicles.Therefore, the design loads of the vehicle is also different from the track vehicles, and car body structure design should be based on its actually operating conditions with reasonable design loads. This paper illustrated the design loads of Low-speed maglev vehicles including static vertical load, dynamic vertical load, torsion load and longitudinal load and compared these loads with the standards of TB/T1335-1996,BS EN12663:2000, JIS E 7106:2006.and determined the designed cases based on these loads to the structure of the low-speed maglev train body.In order to determine the main load supporting locations of car body at the beginning design and provide conceptual model for the designer, a topology optimization model was established reference the basic parameters using three-dimensional design software and the finite element analysis software. Exploring single and static stiffness case compared the topology optimization parameters how to choose and how to influence the optimization results. Finally, a conceptual model was obtained exploring multiple static and dynamic topology optimizations.The car body under frame, end walls, side walls and roof structure were designed in details referencing the topology optimization results. In order to improve the vehicle rigidity and convenient to install equipments, the under frame was designed as the horizontal slider and the middle beam structure. A finite element model was established again after the detailed design. Using the finite model completed the static strength analysis and size optimization. The weight of car body structure reduce from 4.13 tons to 3.09 tons and weight loss ratio up to 25.18%. Car body structure can also meet the strength requirements.