Sang Uk Park, Chan Yong Zun, Doh-Young Park, Jaewon Lim and Hyung Soo Mok
International Journal of Railway, vol. 9, no. 2, pp.41-45, 2016

Abstract : In this paper, a study on the efficiency improvement of the magnetic levitation train using the LIM (Linear InductionMotor) was presented. The maglev train has the advantage of being environmentally friendly since much less noise anddust is produced. However, due to structural limitation, compared to a rotating induction motor, linear induction motor,the main propulsion engine of the maglev train has a relatively greater air gap and hence has the lower operation effi-ciency. In this paper, the relationship between the operating condition of the train and the slip frequency has been inves-tigated to find out the optimum slip frequency that might improve the efficiency of the magnetic levitation train withlinear induction motor. The slip frequency is variable during the operation by this relationship only within a range thatdoes not affect the levitation system of the train. After that, the comparison of the efficiency between the conventionalcontrol method with the slip frequency fixed at 13.5[Hz] and the proposed method with the slip frequency variable from9.5[Hz] to 6.5[Hz] has been conducted by simulation using Simplorer. Experiments of 19.5[ton] magnetic levitationtrains owned by Korea Institute of Machinery and Materials were carried out to verify the simulation results.

Keyword : Linear induction motor, Propulsion control, Slip frequency, railroad car, ATO, Auto train operation