李显鹏,章凯峰,钱黎鸣,徐骏
LI Xian-peng,ZHANG Kai-feng,QIAN Li-ming,XU Jun(Jiaxing Electric Power Bureau

• 1:嘉兴电力局

摘要(Abstract)：

为保证中性点可靠接地,某些500 kV单相主变中性点接地方式为∏型。运行中发现在此接地方式下,系统正常时两接地引下线中会出现较大的异常电流。为此,建立了∏型接地方式的电路模型,应用叠加定理对电路进行了分析,认为在∏型接地方式下,3台单相主变间的两段中性点汇流母线存在电阻,是两接地引下线中出现异常电流的原因,现场实测数据验证了模型的正确性。
Some neutral points of 500 kV single-phase transformers use ∏ grounding to ensure the reliability.High abnormal current is found in the two grounding down leads during normal operation of power system in this mode of grounding.Therefore,the circuit model of ∏ grounding is established.Through the analysis on the circuit by superposition theorem,it is found that the resistance of the two neutral point buses between three single-phase transformers led to the abnormal current of the two grounding down leads.The field test verifies the validity of the model.

关键词(KeyWords)： 变压器;∏型接地;引下线;电流;叠加定理
transtormer;∏ grounding;down lead;current;superposition theorem

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 李显鹏,章凯峰,钱黎鸣,徐骏
LI Xian-peng,ZHANG Kai-feng,QIAN Li-ming,XU Jun(Jiaxing Electric Power Bureau

DOI: 10.19585/j.zjdl.2012.03.007

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