第36卷第2期 2016年4月
核科学与工程
Nuclear Science and Engineering
Vol.36No.2
Apr.2016
核电站低压厂用变压器零序保护的分析与改进
宋鹏飞，冯庆冬
（中广核工程有限公司设计院，广东深期518172)
摘要：核电站低压厂用变压器中性点零序保护采用“定时限”设计，多次出现因低压负荷回路发生单相接地故障引起的低压厂用变压器零序保护越级动作事件。梳理低压厂用变压器零序保护整定原则和分析上下级差保护配合要求，携出低压厂用变压器零序保护采用“定时限十反时限"两段式保护改进方案，
经过保护校验和现场验证，改进方案可在核电站应用和推广。关键调：低压厂用变压器；零序保护；定时限；反时限
中图分类号：TM623.1
文章标患码：A
文章编号：0258-0918(2016)02-0245-06
Analysisandimprovementonzerosequenceprotectionoflow voltageauxiliarypowertransformerinnuclearpowerstation
SONG Peng-fei，FENG Qing-dong
(Design Institute of China Nuclear Power Engineering Co., Ltd, Shenzhen Guangdong, 518172, China)
Abstract: The zero sequence protection for neutral point of low voltage transformer is the definite time characteristic in nuclear power station. Low voltage electrical feeder fault resulted in zero sequence protection of low voltage transformer leapfrog trip. According to the setting principle of zero sequence of low voltage transformer and analysis of protection coordination, the zero sequence protection scheme was improved with definite time and inverse time characteristic. The improved two section protection scheme can be used in the low voltage transformer of nuclear power station after protection checking and onside testing.
Key words:Low voltage auxiliary power transformer; Zero sequence protection; Definite time; Inverse time
核电站低压厂用变压器作为核电站厂用电系统关键电气设备，主要为厂用低压380V/ 220V负荷提供电源。低压厂用变压器单相接
地故障保护可以利用高压侧的三相过流保护，也可以利用低压侧中性点装设专用零序保护实现。
修回日期：2015-06-23
作者简介：宋鹏飞（1986一），男，山西省中市人，工程师，工学学士，现主要从事核电厂电气系统设计工作
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