牵引变流器网侧电流谐波抑制研究

Research on Grid-side Current Harmonic Suppression of Traction Converters

摘要:

作为电力机车牵引传动系统核心部件的牵引变流器是牵引供电网的主要谐波来源之一；牵引变流器采用的单相四象限整流器,输出含有二次脉动,且工作开关频率较低,导致变流器网侧电流谐波问题严重；目前单相四象限整流器的控制脉冲产生主要采用SPWM技术；与SPWM相比,SHEPWM(特定谐波消除PWM)可以针对性的消除特定的谐波,谐波含量更小,效率更高,但其无法消除调制波中本身就存在的谐波；针对SHEPWM调制策略进行了分析设计,同时对陷波滤波器技术、PR控制策略和LC回路在降低谐波含量中的作用进行深入分析；经过合理的方案选择,有效的降低了网侧电流谐波含量,并通过MATLAB仿真实验进行了分析验证。

Abstract:

Traction converters, as the core components of electric locomotive traction-drive system,is one of the main sources of traction power supply grid harmonic. Traction converters using single-phase four-quadrant rectifier output ripple containing secondary and work with lower operating switching frequency, resulting in the converter side current harmonics problem serious. Currently, control pulses of single-phase four-quadrant rectifier, generated mainly by SPWM technology. Compared with SPWM, SHEPWM (Selective Harmonic Elimination PWM) can be targeted to eliminate specific harmonics, harmonic content is smaller, and more efficient, but it can’t eliminate the harmonic which the modulation wave contained. In this paper, analysis and design SHEPWM modulation strategy, and analysis the effect of the notch filter,PR strategies,and LC circuit in reducing the harmonic. After choosing the reasonable scheme, reducing the harmonic effectively, and it analyzed and verified by Matlab simulation experiment.