A.灭磁开关合闸时 B.定子电流突变时或灭磁开关断开时 C.发电机励磁电流过大时 D.转子回路一点接地时
A.5% B.8% C.10% D.12%
A.50Hz B.100Hz C.150HZ D.200Hz
A.空气 B.水 C.绝缘油 D.氢气
A.±3% B.±5% C.±10% D.±15%