中国电机工程学报2017，Vol.37Issue(z1)：12-20,9.DOI:10.13334/j.0258-8013.pcsee.162277
换流变零差保护在故障切除恢复性涌流期间的误动风险分析
Mal-operation Risk Analysis on Zero-sequence Differential Protection of Converter Substation During Existence of Recovery Inrush Due to Fault Removal
摘要
Abstract
Zero-sequence differential protection has become one of the foremost protective countermeasures for EHV and UHV power transformers due to the advantages of high sensitivity and very fast operation speed. It is the common knowledge that it has no need to be equipped with extra countermeasure besides percentage restraint criterion since it is immune to the inrush in theory. However, according to the waveform analysis of the recovery inrush resulting from removal of external fault of converter transformer, it is disclosed that the current bias component due to core saturation of converter transformer may lead to the accumulation of magnetic bias component within the core of TA. In the extreme conditions, this would lead to the distortion of the current coming from TA, and make the zero-sequence differential protection mal-operate. According to the theoretical analysis and simulation tests, the risk of zero-sequence differential protection mal-operation resulting from the inrush due to fault removal does exist in some specific fault conditions. In this case, additional restraint countermeasures are necessary to guarantee the operation security of zero-sequence differential protection.关键词
零差保护/故障恢复性涌流/电流互感器饱和/直流偏磁/误动Key words
zero-sequence differential protection/recovery inrush/TA saturation/DC bias/mal-operation分类
信息技术与安全科学引用本文复制引用
丁苏阳,林湘宁,翁汉琍,张哲原,鲁俊生,李正天,李贞,刘永欣..换流变零差保护在故障切除恢复性涌流期间的误动风险分析[J].中国电机工程学报,2017,37(z1):12-20,9.基金项目
国家自然科学基金青年科学基金(51607106) （51607106）
国家电网公司科技项目(JB71-15-041).Project Supported by the Young Scientists Fund of the National Natural Science Foundation of China (51607106) （JB71-15-041）
The Science and Technology Project of State Grid Corporation of China (JB71-15-041). （JB71-15-041）
