Five-Phase Hybrid Single-/Double-Layer Fractional Slot-Winding PMSM for Torque Improvement Under Third Harmonic Current Injection Condition

• Published in: IEEE transactions on magnetics Vol. 58; no. 8; pp. 1 - 6
• Main Authors: Huang, Jiaxuan, Sui, Yi, Yin, Zuosheng, Yang, Shijie, Zheng, Ping
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.08.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Coils (windings); Current injection; Current loss; Eddy current testing; Eddy currents; Finite element analysis; Five-phase; Force; Harmonic analysis; Harmonics; Machine windings; Magnetism; magnetomotive force (MMF) harmonics; permanent magnet (PM) machine; Permanent magnets; Stator cores; Stator windings; third harmonic injection; Torque; Winding
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2022.3169643

A 60-slot/22-pole five-phase machine with hybrid single-/double-layer fractional slot winding is proposed to improve torque under third harmonic current injection condition. Design process of the proposed machine includes two steps of first combining two sets of 20-slot/22-pole machine windings and then shortening coil-pitch. Due to the special structure of the proposed machine, torque-contributing space harmonics in magnetomotive force (MMF) are improved, and redundant space harmonic in MMF which causes high eddy current loss in permanent magnets is suppressed. The proposed machine is evaluated under two modes of third harmonic current injection, namely constant rms and peak harmonic injection. Compared with 20-slot/22-pole machine, the proposed machine achieves higher torque and lower losses under both third harmonic current injection conditions. Besides, the performance of the proposed machine when injecting only the first or third harmonic current is also analyzed.