变电站主变差动保护动作故障分析

分析国内外差动保护原理特点及对零序电流的处理原则,阐述国外保护如果设置不当,将造成变压器差动保护在区外线路发生单相接地跳闸且重合后误动作机理,提出了在能够保证差动保护灵敏度的前提下保护设置原则,以降低误动作风险。

Fault Analysis of Main Transformer Differential Protection Mal-operation

This paper takes domestic and international main transformer differential protection as an example,it analysed the principle and characteristics of the domestic and international main transformer differential protection,and the processing principle of zero sequence current,it expound the mechanism of transformer differential protection＇s mal-operation because of setting unsuitable, when an single-phase earth protection fault happen out of protection area, this paper provide an protection setting principles to reduce the risk of real-operation ,which still guaranteed the sensitivity of the differential protection