Linear induction motors and rotary induction motors in the principle of work is no essential difference. Just get the mechanical movement in a different way. But both in the electromagnetic performance there is a big difference drama, mainly in the following three aspects:
(1) Rotary induction motors stator three-phase winding is symmetrical. Thus if the applied three-phase voltage is symmetrical. The three-phase current is symmetrical. But the linear three-phase winding of the linear induction motors is asymmetrical in the space position. The coil at the edge is compared to the coil located in the middle. The inductance value is very different. That is to say: phase reactance is not equal. Thus, even if the three-phase voltage is symmetrical. The three-phase winding current is also asymmetrical.
(2) Rotary induction motors set, the rotor of the air gap is round, no head no tail, continuous. There is no beginning and end. But the linear induction motors between the primary and secondary air gap exists between the beginning and end. When the secondary end enters or exits the air gap. Will be in the secondary conductor inductive additional current. This is the so-called "marginal effect". Due to the influence of the edge effect, the linear induction motors and the rotary induction motors are quite different in operating characteristics.
(3) because the linear induction motors early, secondary in the direction of the straight line to continue a certain length, and the normal electromagnetic force is often uneven, so the mechanical structure of the general primary and secondary air gap between the Longer. such. Its power factor is lower than the rotary induction motors.