CAJ | 학술논문

针对一起某110kV数字化变电站主变压器差动保护误动作事故进行了深入分析.根据故障录波数据,通过相关技术人员的现场查找和分析,确定了主变压器差动保护误动的原因,即投电容器时,一次系统产生较大的干扰信号,对主变压器低压侧采样系统产生影响,主变压器低压侧各模拟量通道同时产生较大的向下的尖波,导致主变压器差动保护差流瞬时增大,造成比率差动保护动作.根据现场实际情况和误动原因,提出了相关解决方案,并经过了现场实际验证,为类似事故的预防、解决提供了参考.
침대일기모110kV수자화변전참주변압기차동보호오동작사고진행료심입분석.근거고장록파수거,통과상관기술인원적현장사조화분석,학정료주변압기차동보호오동적원인,즉투전용기시,일차계통산생교대적간우신호,대주변압기저압측채양계통산생영향,주변압기저압측각모의량통도동시산생교대적향하적첨파,도치주변압기차동보호차류순시증대,조성비솔차동보호동작.근거현장실제정황화오동원인,제출료상관해결방안,병경과료현장실제험증,위유사사고적예방、해결제공료삼고.
This paper makes an in-depth analysis of a differential protection malfunction of main transformer in a 110 kV digital substation.The cause is found out through on-site examination and analysis of fault recording data by relevant technical personnel.A large interference signal produced by capacitor switching impact the sampling circuit of the low voltage of main transformer.It lead to large downward sharp wave in all the analog channels of secondary sampling circuit of low voltage side of main transformer at the same time,and resulted in an instantaneous increase of the differential current of differential protection malfunction of main transformer,which caused ratio differential protection malfunction of main transformer.According to on-site actual conditions and the malfunction causes,the related solutions are proposed and verified on-site,which provides experience to prevent recurrence of similar incidents in the future.