Mathematical model and torque ripple reduction for multi-unit permanent magnet synchronous motor

作者：Zou Ji Bin; Zhao Bo^*; Liang Wei Yan; Xu Yong Xiang

来源：Electric Machines and Control, 2012, 16(5): 46-51.

• Analytical expressions
• Current levels
• Direct drive
• Electromagnetic torques
• Energy method
• Harmonic currents
• Low-speed and high-torque
• Multi-unit
• Output power
• Permanent Magnet Synchronous Motor
• Phase winding
• Research object
• Torque ripples
• Torque-ripple reduction

In order to enhance the output power of permanent magnet synchronous motor (PMSM) and reduce voltage and current level of the per phase winding, the multi-phase or multi-unit windings have been often used in the superpower machine designs. Looking a five-unit direct drive low-speed and high-torque PMSM as research object, the multi-unit PMSM voltage and electromagnetic torque equations were established. Nevertheless, when only part of units were operating, analytical expressions of torque ripple produced by the multi-unit PMSM under different quantities and positions were deduced through co-magnetic energy method. The injected 3rd harmonic current was applied to reject torque ripple. Through the numerical analysis and experiments, the results can be seen that mathematical model of this multi-unit motor is accurate and the torque ripple reduction method is effective. The torque ripple can be reduced up to 3.5% when part of units is running. Finally the mathematical model and the torque ripple and its reduction can be conditionally extended to the analysis of multi-unit PMSM with different number of units.

• 出版日期2012