CPR1000机组100D型主泵振动故障诊断

Fault Diagnosis of Vibration Induced by Fluid of 100D Main Pump for CPR1000 Unit

CPR1000机组各运行模式下100D型主泵的振动现象表明,当处于蒸汽发生器冷却正常停堆或余热排出冷却正常停堆工况时,主泵电动机的瓦振幅值往往存在大范围冲击波动甚至触发振动高报警的现象。根据机械振动原理综合分析电动机瓦振、主泵轴位移信号的频域和时域特征,诊断振幅波动受某7~9 Hz的低频随机振动影响;通过分析堆内构件振动噪声监测系统采集的信号判断该低频振动对应一回路主冷却剂流动过程中诱发的堆芯吊篮梁式振动。根据流体诱发振动理论分析了影响主泵电动机振动波动的主要因素,并通过主泵历史运行记录进行了验证。系统性提出优化CPR1000机组运行策略缓解主泵电动机振动波动的建议,为主泵安全稳定运行提供参考。

The vibration phenomenon of 100D main pump under various operation modes for CPR1000 unit show that,when the main pump motor is in normal shutdown condition of steam generator cooling or residual heat removal cooling,the amplitude value of the main pump motor tile often has a large range of impact fluctuation or even triggers high vibration alarm.According to the principle of mechanical vibration,the frequency-domain and time-domain characteristics of motor bearing vibration and main pump shaft displacement signals are comprehensively analyzed.The vibration amplitude fluctuation is affected by the low-frequency random vibration of about 7~9 Hz.The signal collected by the vibration and noise monitoring system is used to analyze the low frequency vibration corresponding to the core basket beam vibration induced by the main coolant flow in the primary circuit.According to the theory of fluid induced vibration,the main factors affecting the vibration fluctuation of the main pump motor are analyzed and verified by the historical operation records of the main pump.The suggestion of optimizing the operation strategy of CPR1000 unit to alleviate the vibration fluctuation of main pump motor is put forward systematically,which provides a reference for the safe and stable operation of the main pump.