整流桥控制角和换相重叠角对谐波影响的分析

Effect of rectifying bridge control angle and commutation overlap angle on harmonic

在电力系统中存在许多复杂电路,往往需要通过计算机仿真来分析问题。特别是对于谐波的抑制和谐波源的研究,线路的精确仿真分析更是必不可少的。首先介绍了谐波的危害和3类谐波源,以其中一种谐波源六脉动整流桥作为研究对象,理论推导分析了控制角和换相重叠角与谐波电流的关系。通过PSCAD/EMTDC软件建立仿真模型,仿真分析了不同控制角和换相重叠角对谐波电流的影响,仿真结果与理论分析结论吻合。故采用合适的控制角和换相重叠角有助于减小谐波电流的危害。本文对谐波分析、谐波预测及谐波治理等方面均有较好的应用价值。

Simulation is an effective approach to analyze the complicate circuits in power system. It is necessary to do accuracy simulations when doing research on eliminating the harmonics and discovering harmonic sources. There are three kinds of harmonic sources which are harmful to power system. Six-pulse Bridge,which is one of the main harmonic sources, is chosen as the research object. The theoretical analysis shows the link between control angle and harmonic current. And it also shows the link between commutation overlap angle and harmonic current. A simulation module is founded with PSCAD/EMTDC software. The result of simulation shows different effect on harmonic current caused by different control angle and commutation overlap angle. It is quite similar to the conclusion of theoretical analysis. So it is helpful to reduce the harmonic harm by choosing appropriate control angle and commutation overlap angle. So the result is benefit for the harmonic analysis, harmonic prediction and harmonic management.