Driving characteristics analysis of stationary discontinuous armature permanent magnet linear synchronous motor for factory automation systems

The stationary discontinuous armatures in permanent magnet linear synchronous motors (PM-LSMs), which consist of several stator sections that are distributed along the track and that the mover with PM is running without thrust force between these sections, have been proposed as a driving source for transportation systems. This design is very economical in long-distance transportation systems in factories, because the armature is engaged only when accelerated and decelerated operation is necessary. However, the stationary discontinuous armature PM-LSM contains the outlet edges which always exist as a result of the discontinuous arrangement of the armature. For this reason, the high alteration of the thrust force and the attractive force produced between the armature’s core and the mover’s permanent magnet when a mover goes through the between the armature’s installation part and non-installation part has been indicated as the problem of the stationary discontinuous armature PM-LSM. As a result, the stationary discontinuous armature design involves the velocity ripple of the mover with PM during acceleration when freewheeling changes over to re-acceleration. We have proposed and examined constant load angle control without position feedback in order to suppress the velocity ripple which occurs at the re-accelerator with the aim of achieving smooth drive of the stationary discontinuous armature PM-LSM. This paper describes the examination of constant load angle control without position feedback with the aim of suppressing the velocity ripple, which occurs in the re-acceleration portion. Also, we have examined the analysis of the effect of the outlet edge on the mover’s drive which exists as a result of the discontinuous arrangement of the armature side based on the re-acceleration characteristics obtained using constant load angle control without position feedback.