Design and Analysis of Variable Flux Arc Permanent Magnet Motor With Multiple Excitations

Abstract

Arc permanent magnet (PM) motors show good prospects in large telescope application. To explore an appropriate arc PM motor (APMM) used in the large telescope drive, this article investigates a variable flux APMM (VFAPMM) with dual-PM excitation (DPM-VFAPMM). The DPM-VFAPMM incorporates the merits of the APMM, the hybrid excited motor, and the DPM excited motor. The motor structure and working principle of the DPM-VFAPMM are described. Then, a special winding cross-connection method is adopted to mitigate the torque ripple caused by the end effect. Finally, the electromagnetic performances of the DPM-VFAPMM, the rotor-PM VFAPMM, the stator-PM VFAPMM, and the surface-mounted-PM VFAPMM are investigated and compared. The comparison results show that compared with the other three motors, the DPM-VFAPMM shows the highest flux linkage, the highest back electromotive force, the highest average torque, the highest efficiency, and the second lowest torque ripple. Simultaneously, the DPM-VFAPMM shows high torque/effective PM usage. The advantages of high average torque and low torque ripple show that the DPM-VFAPMM is suitable for the potential application of the large telescope drive.