A double-sided linear flux-reversal permanent magnet motor with segmental stator for long-stroke application

Abstract

Linear motors are being attracted considerable attentions in many industry applications, such as ropeless elevator and aerospace fields, in which the linear motors can be directly used to contribute linear driving force. Thus, the initial cost of the drive system is expected to be reduced and the operation efficiency can be improved due to the elimination of the rotary-to-linear device. It is widely known that the traditional linear induction motors (LIMs) have been employed in the long-stroke applications for past few years. However, the efficiency of the LIM is relatively low. On the other hand, due to the adoption of high field permanent magnets (PMs), such as Neodymium iron boron, linear PM synchronous motors (LPMSMs) have been investigated widely. However, the LPMSMs inevitably suffer from high cost, especially in the long stroke applications, because one of the armature windings and PMs has to be installed on the long side of the motor.