直线法在接地阻抗测试中的互感分析

Analysis on mutual inductance with beeline method in the grounding impedance test

为了分析引线间的互感,根据镜像理论建立电流极引线在土壤中的镜像和测量系统模型,计算测试引线间的互感抗;并将现场测得的接地阻抗数据分解为阻性成分和感性成分。计算结果与接地阻抗测量结果的对比显示,引线间互感在接地阻抗测量值中所占比重不容忽视。分析结果表明:确保接地阻抗测量结果的准确性,不仅需要对试验结果进行修正处理,还要在测量时避免电流、电压极引线近距离平行布置。

In order to analyze mutual inductance between the down-leads,based on the mirror im age theory builds a mirror image and measurement system model of current pole down-leads in the soil,calculates the mutual inductance between the test down-leads,and separates grounding imped ance measured data of field test into resistance component and inductive component.The comparison of calculation result and measuring result displays that there is a large proportion of the mutual induc tance between the down-leads in grounding impedance measurement values.The analysis result shows that in order to acquire the veracity of measurement result of grounding impedance,ont only need make the modifying treatment for test result but also need avoid the voltage and current pole down-leads parallel arranging in the test.