Detent-Force Analysis and Reduction of Modular Permanent-Magnet Linear Synchronous Motors with Non-overlapping Windings

This paper presents a hybrid method to reduce the detent force of single-sided modular permanent-magnet linear synchronous motors (MPMLSMs) with non-overlapping windings. Firstly, the topology structure of a 6-slot 5-pole MPMLSM with non-overlapping windings is introduced, which the primary consists of several modules. Based on the finite element method (FEM), it is found the main components of the detent force are 2
^nd
, 4
^th
and 12
^th
harmonics. Secondly, the features and influenced structure parameters of detent force components, cogging force and end force, are analyzed. The 2nd harmonic can be much decreased by adjusting the width and height of end teeth, while the remaining harmonics can be reduced by skewing permanent magnets (PMs). Thirdly, the optimization structures of the former 6s5p MPMLSM are obtained based on FEM. With the hybrid method, the 2
^nd
harmonic of the detent force has been reduced to 0.41 N, and the peak-to-peak value of the detent force is optimized to 0.94 N. Finally, a prototype is made and tested. The experimental results verify the effectiveness of the proposed method.