COMPUTER SIMULATION OF THE VERTICAL MOTION OF CONTROLLED-PM LSM MAGLEV VEHICLE

This paper describes the computer simulation of the vertical motion of the Maglev vehicle which is simultaneously propelled and suspended by linear synchronous motors (LSMs) with controlled-PM excitation. Under the assumption that all controlled-PMs on board make the same motion in the verticle direction, nonlinear dynamic equations are derived for the magnet frame with magnet suspension consisting of the controlled-PMs and for the cabin mounted on it through the secondary suspension of pneumatic springs. To compensate for the static instability of the two-mass model, a state feedback controller is designed for the controlled-PM Maglev M-Bahn. A minimum value of a feedback gain $K sb1$ for deviation $ Delta delta sb1$ of airgap length is determined approximately from the locus of closed-loop eigenvalues vs. $K sb1$ of the linearized equations. It is found that there is an essential difference between simulation results based on the nonlinear and linearized equations of motion. Nonlinear simulation results show that a significant improvement in dynamic behavior is achieved by adding the feedback control with a gain $K sb2$ for airgap velocity $ Delta delta sb1$, and that this controller makes the Maglev M-Bahn follow very smoothly a step variation of 4 mm in the armature rail with negligibly small power loss. (AA)