变电站接地网的断点诊断方法

为提高变电站接地网导体断点诊断的效率和精度，提出了通过测量地表磁感应强度的诊断方法。利用变电站接地网频域电磁场计算软件包进行仿真计算，在对仿真计算结果分析的基础上，研制了专用信号激励源，结合变电站实际电磁干扰环境，研制了信号采集、处理系统，基于电磁感应原理探测地表磁场，诊断变电站接地网导体的断点故障，通过仿真计算、模拟地网试验和现场应用，证明了该方法的可行性和诊断定位的准确性。

A Diagnosis Method of Breaking Points in Grounding Grid for Substations

To improve the diagnosis efficiency and accuracy of conductor breaking point in substation grounding grid, a diagnosis method based on measuring ground surface magnetic induction intensity is proposed. Using frequency domain electromagnetic field calculation software package for substation grounding grid, the simulation calculation is carried out; on the basis of analyzing simulation calculation results, a special signal excitation source is developed; and combining with actual electromagnetic interference environment of substation, a signal acquisition and processing system is developed, by which the ground surface magnetic field can be detected based on electromagnetic induction principle and the conductor breaking point fault of substation grounding grid can be diagnosed. The results of simulation calculation, simulated grounding grid test and field application prove that the proposed method is feasible and its diagnosis location is accurate.