摘要
包头地区电网110 kV变压器中性点全部采用经间隙接地运行的方式。当线路发生接地故障并且跳闸时,变压器间隙零序电流保护会出现保护失配误动,造成停电事故。针对变压器间隙保护与系统零序保护的失配动作现象,分析主变间隙保护动作原因及与系统保护的配合情况,提出将包头地区电网部分110 kV变压器中性点直接接地运行,投入其零序保护,退出其间隙保护的方法,进行了线路故障后系统零序电压与零序电流的计算分析及系统零序保护灵敏度的校验,证明了该方案的可行性,并在包头供电局所属110 kV变电站得以成功实施,解决了主变间隙保护与系统零序保护失配的问题。
All of 110 kV transformer neutral points in Baotou electric power network used gap grounding operation way. When the line earthing fault and tripping, transformer gap zero sequence current protection will appear mismatching misoperation, causing blackouts. According to the phenomenon of transformer gap protection and zero sequence protection action, analysis of the mismatch phenomena, actions and reasons of main transformer protection, put forward part of Baotou power network of the 110 kV transformer neutral points operate grounding directly, input the zero-sequence protection, exit the gap protection method. Calculation and analysis of the fault zero sequence voltage and zero sequence current, and the sensitivity calibration of zero sequence protection system, proved that the scheme is feasible, and was carried out successfully in 110 kV substation of Baotou Power Supply Bureau, solved the mismatch problems that the main transformer gap protection and system zero sequence protection.
出处
《内蒙古电力技术》
2012年第4期23-26,共4页
Inner Mongolia Electric Power
关键词
主变压器
中性点
接地
失配
间隙保护
零序保护
main transformer
neutral point
grounding
mismatch
gap protection
zero- sequence protection
