Suspension Characteristics And Optimization Of The Side-Suspended High-Tc Superconductor Maglev System

High-speed rail is the object of China's vigorous development in recent years because of its advantages of large capacity and fast speed among traditional ground high-speed transportation vehicles.However,the air resistance will account for more than 80% of the total traction resistance after the speed of the high-speed rail exceeds 300 km/h.In addition,wheel-rail noise and aerodynamic noise are also difficult to resolve.In order to solve the above problems,the vacuum pipeline transportation system is the future development trend.This system combines vacuum pipe technology and High-Tc superconductor maglev technology.The former can reduce air resistance and the latter can avoid friction caused by contact.However,the research on High-Tc superconductor maglev trains is still in the low-speed stage and lacks high-speed test lines.To this end,the Superconductivity and New Energy R & D Center at Southwest Jiaotong University completed the side-suspended High-Tc superconductor(SS-HTS)maglev train system in 2016.This system changes the permanent magnet track and maglev by 90 degrees to a side-hanging structure.With this structure,the maglev can overcome the centrifugal force it receives while running along the loop.But this structure also makes the operating state of the system different from the conventional High-Tc superconductor maglev system.According to the characteristics of the system's side-suspended structure,this paper studies and optimizes the suspension guidance performance of the system.First,a three-dimensional High-Tc superconductor finite element simulation model is established using the finite element simulation software COMSOL and H formula.This model not only simulates the two-stage displacement of the HTS bulk,but also simulates the combined motion of rotation and displacement simultaneously,and can realize the coupling simulation of multiple HTS bulks.The induced current distribution obtained by simulation can explain the law of levitation force and guiding force,which provides a theoretical basis for this paper.Then,the complicated motion of the maglev is equivalent to a two-stage quasi-static motion process by analyzing the motion state of the maglev.Two-stage quasi-static experiments are performed on the established experimental platform.The field cold height and field cold offset of the system are optimized to improve the suspension guidance performance of the system.Then,the influence of the thickness of the HTS bulk on the weight of the maglev vehicle and the performance of the suspension guidance is comprehensively considered to optimize the thickness of the HTS bulk.By selecting a HTS bulk with a thickness of 9mm,the running speed of the maglev is improved while ensuring the suspension guidance performance.Finally,the coupling characteristics of the two HTS bulks are simulated using the finite element simulation model.And the effects of longitudinal spacing,lateral spacing,and surround angle on the suspension guidance performance of the two HTS bulks are studied.Based on this,the HTS bulks arrangement of the maglev is optimized.