珠海发电厂发电机转子振动异常问题诊断

Diagnosis of Vibration Problem of Generator Rotor in Zhuhai Power Plant

对珠海发电厂2号发电机8号、9号瓦的轴振幅值出现异常增大的问题进行了研究,通过对2号发电机转子轴振与励磁电流、有功功率及无功功率等相关参数的测试,初步判断是发电机励磁电流变化时转子因局部发生临时热弯曲而产生了热不平衡,并分析了导致热弯曲的原因;在机组停机时有针对性地进行了转子重复脉冲试验、静态交流阻抗试验、极平衡试验、两极线圈之间的电压分布试验等,最终确定发电机转子存在匝间短路问题。

The abnormal increase in shaft vibration amplitude of No. 8 and 9 bearing bushes of Generator 2 in Zhuhai Power Plant was studied. Through tests on the shaft vibration, excitation current, active power and reactive power, etc. of Generator 2 rotor, it was preliminarily concluded that locally temporary hot bending of rotor during change of generator excitation current gave rise to thermal imbalance, and causal investigation was made into the hot bending. Repetitive surge oscillograph （RSO） test of rotor, static AC impedance test, polar balance test, voltage distribution test between polar windings were performed during shutdown of unit to confirm the turn-to-turn short circuit problem of the generator rotor.