Short-Primary Linear Induction Motor Modeling with End Effects for Electric Transportation Systems

This paper models and simulates a short-primary linear induction motor (LIM) for an electric magnetic levitation transportation system, considering LIM end effects. The three-phase LIM used in the vehicle application is modeled based on both electrical and mechanical models of a short-primary LIM. As the vehicle moves, the primary inductance of the electric LIM decreases as propulsion speed increases, which should be taken into account to achieve an accurate LIM model design. The vehicle and LIM models are implemented in Matlab/Simulink, which show the decreasing primary inductance as speed increases. A small-scale LIM drive hardware system was built using an Al rail, back iron, and permanent magnets for levitation. The simulation results and experimental results are included using the hardware prototype of the LIM drive system.