李 平（浙江大学建筑设计研究院有限公司，杭州市 310028）

两种接地故障电流计算方法的比较（李平）

Comparison of Two Calculation Methods for Earthing Fault Current

LI Ping(The Architectural Design & Research Institute of Zhejiang University

Co.,Ltd.,Hangzhou 310028，China)

     Abstract：The maximum allowable length of copper wire cable is determined when the circuit breaker is used as the protection against indirect contact through the calculation of earthing fault current, which is normally solved by two calculation methods. By virtue of the comparison of two calculation methods and the difference analysis of results, it is expected to provide designers with the reference value of design data that meets the code requirements.

    Key words：protection against indirect contact;earthing fault current;instantaneous current value of circuit breaker tripper;maximum length of cables;electrical safety;action sensitivity;calculation model;equivalent circuit

  摘　要：通过接地故障电流计算，确定用断路器作间接接触防护时铜芯电缆最大允许长度，通常是通过两种计算方法求解；通过对两种计算方法的比较及结果的差异分析，以期能给设计人员提供满足规范要求的设计数据参考值。

  关键词：间接接触防护；接地故障电流；断路器脱扣器瞬动电流值；电缆最大长度；电气安全；动作灵敏度；计算模型；等效电路

  中图分类号：TU852   　　　　    文献标识码：A

    doi：10.3969 / j. issn.1003 － 8493.2020.12.004