Design of Magnetic Levitation Controller and Static Stability Analysis

In order to realize the stable suspension of the maglev train in the condition of low track beam stiffness, and reduce construction cost of track beam, a electromagnet-elastic-track-carbody model was established based on Newton's second law. Firstly, the vibration information of electromagnet, track beam and carbody was introduced into the control system by the designed state observer; then the feedback gain matrix was obtained using linear matrix inequality. Next, both were utilized for the dynamic simulation by MATLAB to derive the optimal track beam stiffness and quality, which are 200 kN/m and 325 kg, respectively. The analysis results show that compared with the traditional optimal controller based on the Riccati equation, the controller using linear matrix inequality control algorithm achieves a better quadratic performance index. The control strategy is able to realize the system stable suspension at small stiffness and mass of track beam, and stabilize the system after 0.5 seconds or so. The system is robust to some external disturbances.