摘要
在电力机车牵引传动系统中,受到最高开关频率以及输出电压、电流谐波性能的限制,通常需要采用特殊的优化脉宽调制策略。其中,电流谐波最小PWM(current harmonic minimum PWM,CHMPWM)可以使电机电流谐波分量总体最小,从而有助于提高电机控制性能,减小系统损耗,降低开关管的电流应力,而受到越来越多的关注。对不同开关角个数下CHMPWM的开关角随调制比的分布进行计算,之后以异步电机为例,以加权总谐波畸变(weighted total harmonic distortion,WTHD)和单次电流谐波幅值为指标对CHMPWM的电流谐波性能进行了理论分析,并与特定次谐波消除PWM(selected harmonic elimination PWM,SHEPWM)的相应特性进行了对比,最后对CHMPWM下电机的转矩脉动特性进行了研究。仿真和实验结果都证明了理论分析的正确性和CHMPWM的优异性能。
In high power occasions such as traction driving system of AC electrical locomotive, due to the limitation of switching frequency, voltage or current harmonic, optimized PWM strategy is often used, in which current harmonic minimum PWM （CHMPWM） is considered in especial due to its excellent harmonic performance of output voltage and current. It can reduce the current harmonic obviously, thus has great advantage in the improvement of motor control performance and system efficiency. In this paper, the switching angles curves of CHMPWM with respect to modulation ratio are calculated first. Secondly, taking induction machine as the load, the current harmonic performance is studied through the calculation of weighted total harmonic distortion （WTHD） and current harmonic amplitude. The results are compared with those of selected harmonic elimination PWM （SHEPWM）. And then, the torque pulsation under CHMPWM is analyzed in theory. Simulation and experimental results proved the validity of the theory analysis.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2014年第15期2362-2370,共9页
Proceedings of the CSEE
基金
中央高校基本科研业务费专项资金资助(2012JBM101)~~
关键词
低开关频率
脉宽调制
电流谐波最小
转矩脉动
low switching frequency
PWM
current harmonic minimum
torque pulsation
