无刷直流电动机转矩脉动抑制

Torque ripple reduction in brushless DC motor

通过对无刷直流电动机(brushless DC motor,BLDCM)典型PWM调制控制方式的分析,对新型的PWM开关模式进行了研究,证实了它能消除非换相区的非导通相绕组的二极管续流,进而大大降低非换相区转矩脉动。在该电机系统的换相区转矩脉动抑制方面,通过对换相区开与关不同相的上升与下降电流的分析,并基于功率变换器直流侧供电电压与电机反电动势的固定关系能消除换相区转矩脉动的机理,提出了在功率变换器主电路的直流侧增加ZETA变换器,当进入换相区时由可控的ZETA变换器向功率变换器供电,供电电压保持4倍于电机反电动势。通过实验证实了系统的非换相区和换相区转矩脉动抑制效果。

Based on the typical pulse width modulation（ PWM） modulation of brushless DC motor（ BLDCM）,a new PWM switch mode was presented,and to confirm that it can eliminate diode freewheeling of non commutation zone and non conduction phase winding,thereby greatly reducing non commutation torque pulsation. In the commutation torque ripple suppression of BLDCM system,through current analysis of rising and falling of opening phase and closing phase in commutation zone,a ZETA converter in main circuit of inverter was put forward. The ZETA converter eliminates commutation torque ripple based on fixed relationship between DC power supply voltage and the motor back electromotive force（ EMF）.When BLDCM enter the commutation zone,the ZETA converter supply power to the inverter and power supply voltage to maintain four times in the back EMF. The experimental confirmed that non commutation zone and the commutation torque ripple of BLDCM drive system have been improved.