某水电站250MVA发电机主保护方案的研究

Research on Main Protection Schemes of Hydro Power Station Generator

对某水轮发电机作内部相间和匝间短路计算，在发电机孤立运行、空载额定电压且不计励磁调节器作用的工况下，求出最小稳态工频分量短路电流，相应的灵敏系数也是实际最低值。分析表明高灵敏单元件横差、不完全和完全纵差保护构成发电机内部短路的两重或三重化保护功能。

The interphase and interturn short circuits of a hydrogenerator are calculated. The fundamental 50 Hz currents of steady state short circuit are obtained as the generator is operated under no load,rated voltage and without the excitation regulator.The relative sensitivity coefficient is really the smallest value.The analysis indicates that the high sensitivity single transverse differential,non complete and complete longitudinal differential protections constitute multiple protection functions.