方家山核电厂棒位探测器的故障分析及改进措施

Fault Analysis and Improvement Measures for the Rod Position Detector of Fangjiashan NPP

为找出方家山核电厂实测棒位指示系统在调试期间出现的棒位跳变异常原因,结合方家山核电厂电磁感应棒位探测器的工作机理,从棒位测量柜的接线、电缆的绝缘、系统编码卡件和棒位探测器内部的影响入手对调试期间出现棒位光点异常跳变的现象进行系统分析和逐一定位,最终找到了导致此次棒位异常指示的确切原因,并提出了相应的后续改进措施,也得到了实际验证,这对棒控棒位系统的稳定可靠性运行有着重要意义,该故障分析方法和改进措施对使用此类棒位探测器的压水堆核电站也有借鉴作用。

In order to find out the cause of the rod position jump anomaly that occurred during commissioning of the actual measured rod position indication system of Fangjiashan NPP,the precise cause of the abnormal hop is analyzed systematically and positioned one by one by combining the working mechanism of the electro-magnetic induction rod position detector of pressurized water reactor,from the wiring of the rod measurement equipment,the insulation of the cable,the encoder module and the internal influence of the rod position detector.In the end,the root cause of the abnormal indication of the rod position is found,and the corresponding improvement measures are proposed,which is of great significance to the operational reliability of the rod control and rod position system.This fault analysis and improvement measures can also be used as a reference for other PWRs using this type of rod position detector.