Vibration Reduction for Dual-Branch Three-Phase Permanent Magnet Synchronous Motor With Carrier Phase-Shift Technique.

In motor drive system, ear-piercing acoustic noise caused by high-frequency vibration from motor becomes unacceptable in sensitive environments, due to the application of pulsewidth modulation (PWM) and consideration of switching losses. In this paper, a novel method which associates a presented dual three-phase permanent magnet synchronous motor (PMSM) called dual-branch three-phase PMSM with carrier phase-shift technique is implemented to completely reduce odd-order PWM frequency vibration. The proposed motor has two no phase-shift three-phase windings, whose coils wind on the same teeth; it is driven by paralleled inverters with magnetically coupled inductors. With carrier phase shifting $\pi $ , the odd-order carrier frequency current harmonics with the identical amplitude in two windings are opposite in phase, and therefore the produced magneto-motive-force (MMF) harmonics in the air gap offset with each other. The experimental results are provided to verify the validity of the proposed method in vibration reduction. Compared with the previous work of vibration reduction for dual three-phase PMSMs, the proposed method can achieve total elimination of odd-order PWM frequency vibration. [ABSTRACT FROM AUTHOR]