基于分布式光纤拉曼测温系统的核电一回路泄漏点监测技术

Monitoring Technology of Nuclear Power Primary Circuit Leakage Point Based on Distributed Temperature Sensor

为了能对核能发电站内反应堆冷却系统管道的泄漏情况进行实时监测及高精度定位,利用拉曼散射效应和光时域反射技术构建了分布式光纤测温系统,结合特定规则的传感光纤布设方式,实现管道外壁温度场的全覆盖式实时在线监测.通过实验验证,当泄露发生导致二维平面内某区域的温度异常达到预先设置的阈值时,监测系统会依据布线规则对该点进行位置解码并标记,从而实现二维平面的精确定位.实验得到的定位精度为0.5m,并显著降低了误报可能性,可极大的提高管道外表面温度异常点的定位精度.

In order to monitor and accurately locate the leakage of the reactor cooling system in the nuclear power station,the distributed temperature sensor is constructed by using Raman scattering effect and optical time domain reflection technology.Combined with the specific rules of the sensing fiber layout,to achieve full coverage online monitoring of the temperature field outside the pipeline in real-time.It is verified by experiments that when the leakage causes the temperature anomaly in a certain area of the two-dimensional plane to reach a preset threshold,the monitoring system will position and mark the point according to the wiring rules,thereby achieving accurate positioning of the two-dimensional plane.The positional accuracy obtained by the experiment is 0.5 meters,and the probability of false alarms is significantly reduced,which can greatly improve the positioning accuracy of the abnormal point of the temperature on the outer surface of the pipeline.