电压互感器二次回路异常对线路保护的影响

微机保护装置都有较完善的电压互感器断线检测功能,当系统正常运行时发生电压互感器二次回路断线,能够及时给予指示并闭锁故障时可能会误动的保护。针对电压互感器二次两点或多点接地对保护装置的影响只有在系统故障时才反映出来,从理论上分析了系统发生接地故障时,保护装置测量到的电压与系统实际电压的差异,研究了受影响的保护的动作行为,并通过现场实录的波形进行验证,提出查找两点及多点接地的方法。

The Influences of Secondary Loop Abnormality of Voltage Transformer on the Protection of Transmission Line

The disconnection of voltage transformer can be detected by the protective device in computer,which can also give timely instructions and lock the possible malfunction protection.Based on that the influences of voltage transformer grounding two or more points on protection device are only reflected when system fails,the differences between the voltage measured by protective device and the actual voltage are analyzed theoretically,and the influenced operation of the line protection is studied and verified by...