摘要
某变电站10 kV系统发生接地故障,引起多条10 kV线路低频减载保护连续误动作。通过对现场故障录波波形及UT-9911A线路保护装置低频减载保护频率算法进行分析,认为10 kV系统单相接地引起的铁磁谐振导致母线电压严重畸变,保护装置测频出错,进而造成低频减载保护误动作。更换二次消谐装置后该变电站再未发生同类故障。并就此类故障提出相应的防范措施。
Grounding fault occured in the 10 kV power system in some substation,which caused protection misoperation of some 10 kV lines constantly.The analysis of fault waveform and frequency algorithm of under-frequency load shedding device concluded that ferro-resonance was the cause of protection misoperation of under-frequency load shedding,leading to bus voltage aberrance seriously,wrong frequency measurement for protection device,which caused protection misoperation.And take the measurement of replaying the secondary harmonic elimination.Simultaneously,some preventive measures were raised to avoid the same faults.
出处
《内蒙古电力技术》
2015年第5期72-74,共3页
Inner Mongolia Electric Power
关键词
10
KV线路
低频减载保护
铁磁谐振
单相接地
测频
二次消谐
10 kV lines
under-frequency loading shedding
ferro-resonance
single-phase earthing
frequency measurement
secondary harmonic elimination
