全并联AT牵引网高次谐波谐振及抑制方案研究

Research on High Harmonic Resonance and Suppression of All Parallel AT Power Supply System

当机车发出的谐波电流分量与牵引网固有谐振频率相等或接近时,可能激发车网系统发生谐波谐振,从而在牵引网上形成过电压和过电流。引入机车诺顿等效模型,分析并联谐振和串联谐振的产生机制及其特性。仿真结果表明:谐振发生时,单位谐波电流的注入会在牵引变电所产生数千伏谐波电压,馈线谐波电流被放大近10倍;牵引网电压和馈线电流的升高主要是和并联谐振有关,串联谐振对网压和馈线电流的升高基本无影响。仿真结果验证了在牵引网上设置二阶阻尼滤波器的有效性,并对其安装位置进行了探讨,对AT牵引供电系统高次谐波谐振研究和抑制技术应用提供了参考。

When the frequency of harmonic current caused by the locomotive is equal or close to the resonance frequency of trac- tion network, harmonic resonance will occur in the system and overvoltage and overcurrent will be produced in traction network. The NORTON equivalent mode/of locomotive was set up and the mechanism of parallel resonant and series resonance and its features were analyzed. Simulation results show that once the resonance occurs, the unit of the harmonic current injection produces a few kV harmon- ic voltage in traction substation, and the harmonic current amplification is nearly 10 times. The traction network voltage and feeder cur- rent rise are mainly related to parallel resonant points, and the rise of network voltage and feeder current have little to do with series resonant points. The effectiveness of harmonic suppression scheme based on second-order damping filter was verified. The installation position of the filter were discussed in this paper,which can provide guidance for the high harmonic resonance research and the engi- neering application of harmonic suppression scheme.