两相导通型凸极式永磁无刷直流电机DTC中换相区间转矩跌落抑制策略

两相导通空间矢量调制型直接转矩控制SVM-DTC(space vector modulation-direct torque control)可以有效抑制永磁无刷直流电机BLDCM(brushless DC motor)非换相期间转矩脉动及换相期间的转矩增长现象,但却不能抑制换相期间的转矩跌落现象。为此,对凸极式BLDCM SVM-DTC方法中换相区间转矩脉动进行了分析,提出一种抑制高速区换相区间转矩跌落新方法。根据转矩跌落的大小,调节关断相功率管的占空比,以达到抑制非换流相电流跌落和抑制转矩脉动的目的。实验结果验证了所提转矩跌落抑制控制策略的有效性。

Torque Drop Suppression Strategy for Two-phase Conduction-type Salient-pole Permanent Magnet Brushless DC Motor in DTC

Two-phase conduction-type space vector modulation direct torque control(SVM-DTC) can effectively su-ppress the phenomena of torque ripple during non-commutation and the growing torque during commutation, but it cannot suppress the phenomenon of torque drop during commutation. To this end, the torque ripple of salient-pole brushless DC motor(BLDCM) under SVM-DTC in commutation interval is analyzed, and a novel method for suppressing torque drop in high-speed commutation interval is proposed. According to the size of torque drop, the duty cycle of the off-phase power tube is adjusted to suppress the current drop during non-commutation as well as torque ripple. Experi-mental results demonstrated the effectiveness of the proposed torque drop suppression control strategy.