Design and optimization of an arc vernier permanent magnet synchronous motor used for large telescope

The torque ripple of arc permanent magnet synchronous motors (PMSMs) is significant for the positioning precision and tracking accuracy of the large telescope. In this digest, an arc vernier PMSM is proposed, which fully utilizes the advantage of vernier machine with low torque ripple and high torque density. The stator length and the relative positions of different stators are optimized to reduce the end cogging force. Moreover, a conventional arc PMSM with fractional-slot concentrated windings (FSCWs) is built and compared with the proposed arc vernier PMSM.