The controller design and performance index analysis of Maglev train´s suspension system

The mathematic model considering magnetic flux loss of Maglev train and the design of PID controller are studied. During the process of analysis and design of PID controller, some new performance indexes, which were firstly put forward by Wang Guangxiong and are used to judge sufficient stable degree for controlling unstable system, are studied. Bode plot is used to validate the modified phase margin. Compared to Wang´s conclusion, the more widely accepted phase margin is brought forward. Furthermore, the PID controller and performance indexes are validated by nonlinear simulation model.