Vector control for linear induction machine with minimization of the end effects

Due to of its geometry, the Linear Induction Motor (LIM) has an end effects phenomena causing weakening of the air gap flux and the thrust force. In this work, we described the end effects of the motor by introducing speed dependent scale factors to the magnetizing inductance and series resistance in the d-axis equivalent circuit. Thrust force and flux equations are therefore modified. Also, a field orientation control scheme is developed taking into account the end effects. Starting from this study, the problems of the primary current variations, due to the end effects, is evaluated by simulation. To minimize the end effects in a linear induction machine a new order is developed. This control consists in imposing a primary flux φ_dr in order to minimize losses.