摘要
大型发电机内部结构复杂,单相接地故障会导致定子绕组电势不平衡问题,使得最终定位结果相对误差较大。为解决大型发电机在运行过程中可能出现的单相接地故障问题,需对大型发电机注入式定子绕组单相接地故障定位方法进行研究。分析大型发电机注入式定子绕组结构,构建暂态网络模型,明确定子绕组工作模式。根据发电机定子线棒接线图,绘制定子分支电势分布图。从定子结构特性出发,建立单相接地电势相量近似分布图,通过数学推导获取电势相位角。考虑绕组电势相位特征的情况下,利用零序电压、故障相电势、过渡电阻等参数,定位具体的单相接地故障位置。研究结果表明:该方法故障定位结果相对误差始终低于1%,满足故障定位要求。
Due to the complex internal structure of the generator,single-phase grounding fault will lead to potential imbalance in the stator winding,especially in large generators.It is easy to ignore the potential phase characteristics of the stator winding,which makes the relative error of the final positioning result larger.Therefore,a method for locating single-phase ground fault in injection stator winding of large generator was proposed.The structure of injection stator winding of large generator was analyzed,the transient network model was established,and the working mode of stator winding was defined.Based on the wiring diagram of the stator rod,the stator branch potential distribution diagram was drawn.Based on the stator structure characteristics,the approximate distribution diagram of single-phase ground potential phasor was established,and the potential phase angle was obtained through mathematical derivation.Considering the phase characteristics of winding potential,zero sequence voltage,fault phase potential,transition resistance and other parameters were used to locate the specific single-phase grounding fault location.The experimental results showed that the relative error of the proposed method was always less than 1%,which can meet the requirement of fault location.
作者
覃战
QIN Zhan(Zangmu Hydropower Plant,Huaneng Tibet Yarlung Zangbo Hydropower Development Investment Co.,Ltd.,Shannan 856417,China)
出处
《水利水电快报》
2024年第8期84-88,共5页
Express Water Resources & Hydropower Information
关键词
发电机
注入式定子绕组
单相接地故障
行波理论
绕组电势
故障定位
generator
injection type stator winding
single phase ground fault
traveling wave theory
winding potential
fault location
