用于距离保护的静态稳定破坏检测方案

传统的线路保护静态稳定破坏检测需要人工对特定定值进行整定,并且当振荡中心在线路之外时可能无法检测出振荡.而在这种工况下再发生故障时,距离保护动作行为将会不正确,同样需要振荡闭锁.文中分析了静态稳定破坏检测判据的原理及存在的问题,提出一种利用Ucos及其变化率来检测系统是否失去静态稳定的判据,该判据不依赖于整定,不受振荡...

A Static Instability Detecting Scheme for Distance Protection

Traditional static instability detecting for line protection depends on artificial setting the specific value.And when the power swing center is outside the line,the swing may not be detected.If faults occur again under such circumstances,the distance protection will wrongly act and needs swing block.A novel static instability detecting criterion based on the characteristic of Ucos φ and its change rate is presented.The criterion is independent of setting and immune from the swing center location.Simulation results demonstrate that the protection at both sides of the line can detect static instability fast and reliably with the criterion proposed,so that mal-operation of the line protection may be prevented by adopting effective measures.