Analysis of outlet edge cogging force in permanent magnet linear synchronous motor having the stationary discontinuous armature

Recently, permanent magnet type linear synchronous motors have been used as a driving source of transportation systems, to satisfy requirements such as speeding up of transportation systems and also to simplify maintenance. We have proposed a stationary discontinuous armature PM-LSM in which the armature is engaged only when accelerated and decelerated operation is necessary, in order to resolve the problem of higher costs, when PM-LSM is used with long-distance transportation systems in factories. However, the stationary discontinuous armature PM-LSM contains the outlet edges which always exist as a result of the discontinuous arrangement of the armature. These edges become a problem, because the cogging force that they exert influences the controllability of the motor Therefore, we considered deforming the shape of the outlet edge at the armature and apply skew on the permanent magnet of the mover in order to reduce the cogging force of the outlet edge. This paper presents the results of 3-D numerical analysis by FEM of the cogging force exerted by the outlet edge.