Two designs of single-sided linear induction motor (SLIM) were proposed to satisfy the required traction of medium-low speed maglev train. Between these two designs,one has a primary core with 8 poles and 80 slots and a length of 1 927 mm,while the other one is a 8-pole-89-slot design with a length of 2 047 mm. With limited installation space and cost as constraints,magnetic flow path,magnet-motive loop,equal circuit coefficients and initial characteristics were calculated so that fast and accurate determinations of the winding number of poles,pitch,the number of turn,groove and wiring become possible. Theoretical calculation and FEA simulations were performed and the results showed that both designs satisfy the traction requirements of medium-low speed maglev trains. The 8-pole-80-slot SLIM is already in quantity production stage,and the feasibility of the 8-pole-89-slot design has been proved. The proposed design procedure of SLIM and the methods to calculate relative characteristics can not only be applied to optimize SLIM designs for medium-low speed maglev trains,but also provide a method to precisely calculate the static values of those variables for dynamic control of a SLIM.