基于灵敏度的接地引下线偏移对接地网故障诊断的影响研究

因测量的接地引下线就近归算到接地网拓扑结构的交叉点造成可测节点位置偏移,对接地网故障诊断中端口电阻的测量产生影响,依据电网络理论推导出引下线偏移的灵敏度公式,并分析总结引下线偏移距离大小对端口电阻测量值的影响。同时,在4×4的模拟地网中,假设在引下线未偏移、偏移12.5%、偏移25%、偏移50%共四种条件下,分析偏移对诊断接地网支路电阻值影响,在工程上有较好的指导作用。

Research on the Influence of Grounding Down Line Deviation to Fault Diagnosis of Grounding Grid Based on Sensitivity

To evaluate influence to the port resistance measurement in fault diagnosis of grounding grid, for the touchable nodes deviation due to the normalization of downing down line positions to the nearby nodes, a sensitivity equation is derived based on electric network theory, and the law of grounding down line deviation impact on the port resistance is summarized. An experimental grounding grid with sixteen branches is used as an example, assuming grounding down lines are not deviated, deviated by 12.5%, 25%, 50% of the total of the four conditions, the impact of deviation to diagnosis of branch resistance can be obtained, and it has a better guide effect in field.