A new double-sided primary wound field flux-switching linear motor

In this paper, a new double-sided primary wound field flux-switching linear (PWFFSL) motor is proposed, in which the yokeless iron, DC field and armature windings are all located in the short primary mover, while the long double-sided secondary stator is only made of iron. Also, this motor can offer sinusoidal and symmetrical back-EMF and smaller force ripple, because each phase includes two armature coils whose positions are mutually 180 electrical degrees apart. Hence, these kinds of linear motors incorporate the merits of simple structure and low cost of linear switched reluctance (LSR) motors and simple control due to its sinusoidal back-EMF of linear synchronous PM (LSPM) motors, which are perfectly suited for long stator applications such as elevator system. By means of finite element analysis (FEA), the proposed double-sided PWFFSL motor has been optimized and compared with a LSR motor based on the same overall dimension. The results show that the proposed motor can offer higher thrust force and lower force ripple.