Design of the Permanent Magnet Linear Synchronous Motor for High Thrust and Low Cogging Force Performance

Permanent magnet linear synchronous motors (PMLSM) are well known for its high thrust performance. However, such high thrust can be distorted by the existence of cogging force due to the attraction between stator core and permanent magnet (PM). To improve its performance, two parts of the PMLSM structure were considered during the design. They are PM magnetization arrangement on mover side and stator slot opening parameters on stator side. The designed models were simulated by using FEM software, and the performances of the models are then compared. The aim of the design is to achieve high thrust and low cogging force characteristics. Apart from average thrust F-ave and cogging force F-cog, the performance of the PMLSM is also evaluated using average thrust F-ave to cogging force ratio Fcog, called as thrust ratio. Based on the design, the highest thrust ratio F-ave: F-cog, obtained from radial, axial and Halbach models, are 2.5032, 2.6262 and 1.8437, respectively.