Maglev Vehicle System Dynamics

Maglev train is a new type of ground tracked transport tool, which advantages such as non-contact suspension and propulsion, superspeed run, comfortable ride quality, friendly environment compatibility are attractive and competitive in the 21 century. In the past thirty years, the research and development (R&D) in maglev technology had made a great progress. Nowadays, German high-speed electromagnetic suspension (EMS) transport system-Transrapid and Japanese electrodynamic suspension (EDS) maglev train-MLX01 is ready to the revenue application. Moreover, China had obtained the key technologies of electromagnetic suspension and guidance from the R&D on medium-low speed EMS maglev vehicle since the early 1980s, and few demonstration lines of low-speed EMS maglev train had been constructed in the last few years. Recently, Shanghai high-speed maglev railway adopting the German Transrapid technology is preparing for first test run. The above-mentioned development in maglev technology shows that maglev railway is coming into our life. However, it is well know that the dynamic responses of maglev ground transportation system have important consequents for system safety and ride comfort of passenger, guideway design, and system costs. So the study of maglev vehicle system dynamics is necessary and important to boost the application technology of maglev railway in our country.In this dissertation, studies on the magnet/rail relationship, the interaction of maglev vehicle/elevated-guideway systems, the random vibration of maglev vehicle, the lateral dynamics and curve negotiation of maglev vehicle are carried out by means of theoretic analysis and numerical simulation. The purposes of the paper are to reveal the dynamic characteristics of electromagnetic suspension, to show the dynamic interaction between maglev vehicle and the elevated-guideway, to evaluate ride quality and curve negotiation performance of maglev vehicle, and to obtain the guidelines of optimization design of maglev dynamic system. The main contents and results are as follows.Since the electromagnetic forces have strong influence on dynamic responses of maglev vehicle/guideway system, the study of magnet/rail relationship is the key and fundamental content in maglev system dynamics. Chapter II firstly investigates the dynamic stiffness and damping of electromagnetic suspension considering the mechanical-electromagnetic coupling field and suspension control system, as well asthe guidance stiffness and damping under the passive control and active control. Subsequently, the dynamic model of magnet/rail interaction embodying a single magnet suspension system and the flexible guideway is established to simulate the system dynamic responses in the takeoff operation. Numerical results show that the mechanic performance of electromagnetic suspension. And they also show that the suspension instability results from the irrational configuration of system frequencies. Chapter II provide the basic theory for the frequency design of maglev vehicle/guideway systems and magnet/rail model for the following dynamic simulation of maglev system.Due to the strong coupling interaction between maglev vehicle and the elevated-guideway, Chapter III calculates the vertical dynamic responses of maglev vehicle/guideway system based on German TR06 maglev vehicle and the Emsland guideway structure including the single-span concrete beam and the two-span steel beam. The numerical results indicate that the mid-span displacement of guideway is less than the allowable value when TR06 runs over whichever kind of guideway at 360km/h speed, and the comparative studies between the maglev vehicle/guideway interaction and the wheel-rail vehicle/bridge interaction show that the ride quality of TR06 maglev vehicle is much better than that of the wheel-rail vehicle, and the dynamic effect of maglev vehicle on small span beam is smaller than that of wheel-rail vehicle. The conclusions in this chapter can guide the design of secondary suspension system and guideway structure. Additional...