整流电路对谐波及零序电流的影响研究

Research on the Influence of Rectification Circuit on Harmonic and Zero Sequence Current

谐波电流是影响配电系统安全运行的主要因素之一。然而整流电路是主要的谐波源,不同的整流结构产生的谐波电流在大小和次数上均不相同,另外由于整流电路的电流具有脉动的特点,在三相四线系统中容易产生较大的零序电流。文章就三相四线系统针对三路单相整流电路、两路整流电路、单路整流电路及三相全桥整流电路进行仿真研究,结果表明三路单相整流电路在产生谐波电流的同时,还产生很大的零序电流;而三相全桥整流电路仅产生谐波电流,并不会产生零序电流。并于实际配电系统进行测试,实际测试结果与仿真结果一致。

Harmonic current is one of the main factors affecting the safe operation of distribution systems.However,rectifier circuits are the main harmonic source,and the harmonic currents generated by different rectifier structures are not the same in size and frequency.In addition,due to the pulsating characteristics of the current in rectifier circuits,large zero sequence currents are easily generated in three-phase four wire systems.The article conducts simulation research on three-phase four wire systems for three single-phase rectifier circuits,two rectifier circuits,single rectifier circuits,and three-phase full bridge rectifier circuits.The results show that the three single-phase rectifier circuits not only generate harmonic currents,but also generate large zero sequence currents;The three-phase full bridge rectifier circuit only generates harmonic currents and does not generate zero sequence currents.And it was tested on the actual distribution system,and the actual test results were consistent with the simulation results.