摘要
大型发电机和超高压变压器的后备保护经常采用阻抗继电器。有些人误认为,后备阻抗保护对发电机定子绕组和变压器各侧绕组的相间、匝间短路、YN侧的单相接地短路有很高的灵敏度。实际上后备阻抗保护对发电机定子绕组和变压器绕组的各种内部短路的灵敏度往往很低,达不到绕组短路近后备保护的目的,它只能是发电机和变压器三相引线以及相邻线路和母线的后备保护。数字仿真计算充分证明上述结论的科学性。
The impedance relay is usually used as a backup protection for large-sized generator and extra-high voltage transformer.It is misunderstood that the backup impedance protection is high-ly sensitive to the inter-phase fault,inter-turn fault and single phase-to-ground fault at star winding of the windings of generator and transformer.Actually,its sensitivity to most internal winding faults of generator and transformer is so low that it can only be used as the backup protection for the three-phase leading wires of generator and transformer,adjacent lines and bus bars.It can't be used as short-range backup protection for the generator and transformer.Digital simulation verif ies the conclusions.
出处
《电力自动化设备》
EI
CSCD
北大核心
2003年第9期1-4,共4页
Electric Power Automation Equipment
关键词
主设备
后备阻抗保护
灵敏度
main equipment
backup impedance protection
sensitivity
