反向分支支路故障对距离保护的影响  

Effect of Reactive Equivalent Fault Impedance on Distance Protection

作　　者：沈冰[1] 何奔腾[1] 

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027

出　　处：《电力系统自动化》2006年第21期66-70,共5页Automation of Electric Power Systems

摘　　要：反向经分支支路故障对距离保护的影响以前未能引起关注,文中结合实用的四边形继电器特性对这种故障情况进行了系统的分析,得到这种故障条件下测量阻抗和方向阻抗的变化轨迹及其特性,提出了方向特性门槛的参数的参考选择范围,发现了现有的四边形特性方向距离保护在反向经分支支路故障时有误动的可能。Impedance between faulted line and ground is generally regarded as a resistance, but in some cases the equivalent impedance can be reactive. Fault on a transmission line connected to the bus behind the protection is equal to fault on the bus through a reactive ＂fault impedance＂. This problem has rarely been noticed. The impedance loci with fault impedance seen by the protection in this condition is analyzed. The theoretical analysis and digital simulation results show the possibility that distance protection with quadrangular characteristic may real-operate under this condition.

关 键 词：距离保护 过渡电阻 电力系统 

分 类 号：TM77[电气工程—电力系统及自动化]