三相非线性负载时中线谐波电流和电压分析——兼论医院电气设计中的谐波治理与接地系统的关系

Analysis for Harmonic Current and Voltage on Neutral Line When the Three-phase Circuit Non-linear Loads:On Harmonic Control and Grounding System in Hospital Electric Design

通过对三相非线性负载时正弦电流畸变波形的数学分析,论证中性线上存在剩余基波和谐波电流,以及中性点上谐波电压存在的原因,给出三相电源负载与中性点上电压的关系式,为三相非线性负载下接地系统的选择提供参考依据。

Based on math analysis of the distorted wave of sinusoid electric current when the three-phase circuit non-linear load,the article probes the cause why there remains fundamental wave and the harmonic current on neutral line,and the cause of the existence of harmonic voltage on neutral point.In order to choose a suitable grounding system under three-phase nonlinear loads,the article also probes the relationship between the voltage and three-phase non-linear loads in mathematical expression.