A study on efficiency of magnetic levitation trains using linear induction motor by slip pattern

Linear induction motors used in magnetic levitation (maglev) trains use a higher constant slip frequency operating scheme than rotary motors to meet thrust and normal force requirements. Thus, the constant slip frequency is used in all operation conditions, which reduces the efficiency of the propulsion system. In this paper, a varying slip frequency control is proposed for increasing the propulsion efficiency within the limit of vertical force disturbance. The operation pattern of the actual train is defined by the route travel plan, which is adopted in simulation. The proposed varying slip frequency control pattern is verified by the actual maglev train test. With the proposed algorithm, efficiency consumption is improved not only in the propulsion system but the total power in the maglev train operation.