用于高温气冷堆燃料元件检测的外装式检测系统

为准确检测球床式高温气冷堆装卸料系统不锈钢管道内燃料球的过球信息,该文设计了外装式过球信息检测系统。该系统的涡流传感器采用了双半圆结构,其安装和维护都无需破坏过球管道。信号处理部分采用了直接数字频率合成技术(DDS)、高速鉴频鉴相技术和幅值检波技术,有效提取了过球信号,并通过阈值判断和形状比较相结合的方法,准确区分了过球信号和干扰信号。实验表明,在过球速度为0.1～10m/s范围内,该系统能够准确地检测离散过球和连续过球。

External detection system for ball fuel elements in high temperature gas cooled reactors

The fuel element loading-unloading system is one of the most important parts of a pebble-bed high temperature gas cooled reactor (HTGR). The reactor power control and safety depend on accurate detection of the fuel balls in the stainless steel pipeline of the fuel element loading-unloading system. Sensors can not be easily placed inside the pipeline or in the pipe wall. Therefore, an extend detection device was designed. The eddy current sensor has a double semicircular structure, so that it can be installed and maintained without disrupting the pipeline. The sensor uses direct digital synthesis, ultrahigh speed phase/frequency discrimination and an amplitude detector in the signal handling system. Threshold and wave shape analysis are used to distinguish the ball signal from interference. Experiments show that the detection system accurately detects discrete and continuous ball-passes at speeds between 0.1 m/s and 10 m/s.