某220kV变电站,已知其站区的土壤电阻率ρ为1OOΩ*m,若接地短路(故障)电流的持续时间t取0.4s,试计算接地装置的接触电位差和跨步电位差的允许值,...

作者: rantiku 人气: - 评论: 0
问题 某220kV变电站,已知其站区的土壤电阻率ρ为1OOΩ*m,若接地短路(故障)电流的持续时间t取0.4s,试计算接地装置的接触电位差和跨步电位差的允许值, 跨步电位差允许值计算结果是()。
选项 A.315V; B.386V; C.405V; D.478V。
答案 B
解析 根据DL/T 621—1997P3第3.4条计算公式计算如下

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