A Decoupling Control Scheme of Combined Levitation-and-Propulsion SLIM for Maglev Vehicle

The normal force existing in the single-sided linear induction motor (SLIM) varies with different operation condition. It is always restrained as far as possible since it has serious influence on the performance of SLIM. In this paper, the relation between normal and thrust forces is analyzed. Decoupling control of the two forces is achieved by the appropriate choices of voltage vectors in PWM inverter. Then, the normal and thrust forces are applied independently to levitate and propel a SLIM maglev vehicle without additional levitation magnets. Experiments have been carried out on the combined levitation-and-propulsion SLIM maglev vehicle with different operation conditions, during the whole running period, the gap length and speed of the vehicle follow well with the command ones, the stability and accuracy are well proved. The effectiveness of the proposed decoupling control scheme is verified.