高精度电容式棒位测量传感器静态特性研究  

Research on Static Characteristics of High Precision Capacitance Rod Position Measurement Sensor

作　　者：李彦霖 秦本科[1] 薄涵亮[1] LI Yanlin;QIN Benke;BO Hanliang(Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学核能与新能源技术研究院,北京100084

出　　处：《原子能科学技术》2022年第12期2564-2572,共9页Atomic Energy Science and Technology

基　　金：清华大学实验室创新基金(201934)。

摘　　要：控制棒水压驱动系统是200 MW低温核供热堆的关键功率控制设备,电容式棒位测量传感器是该驱动系统的核心测量部件。针对被测杆偏心引起的测量误差,本文提出了能将被测杆步进与偏心所引发的电容变化量实现分离的测量方法(偏心-步进分离方法),依据该方法提出了四螺旋电极电容式棒位测量传感器的设计方案。针对该传感器,利用有限元方法建立了理论模型,开展了传感器静态特性实验,理论模型结果与实验结果符合良好。利用理论模型建立了电容与棒位的函数关系,系统分析了新型传感器的测量误差,完成了传感器的结构优化。结果表明,四螺旋电极电容式棒位测量传感器配合偏心-步进分离方法,在计算工况内最大测量误差为-3.11 mm,能满足棒位测量不失步的要求。该成果可为电容式棒位测量传感器的后续改进提供指导。Control rod hydraulic drive system(CRHDS) is the key power control equipment of 200 MW Nuclear Heating Reactor(NHR-200), and the capacitance rod position measurement sensor(CRPMS) is the key measurement equipment of CRHDS. For the measurement error caused by the eccentricity of the measuring rod, a new measurement method which can separate the capacitance variation caused by the stepping and eccentricity of the measuring rod was proposed(eccentricity-stepping separation method). Based on this method, a design of four-helix electrodes CRPMS was proposed. For the sensor, the theoretical model was established by finite element method, and the static characteristic experiment was carried out. The calculation results of the theoretical model are in good agreement with the experimental results. Based on the theoretical model, the function between capacitance values and rod positions was established, and the measurement error of the sensor was systematically analyzed. The structure optimization of the sensor was conducted. The results show that for the four-helix electrodes CRPMS with eccentricity-stepping separation method, the maximum measurement error is-3.11 mm under the calculation conditions, which can meet the requirements of rod position measurement without losing step. The results provide guidance for the improvement of CRPMS.

关 键 词：控制棒棒位 电容式传感器 四螺旋电极 偏心-步进分离方法 

分 类 号：TL375.5[核科学技术—核技术及应用]