基于谐波参数化方法预测控制棒棒位  

Research on Harmonic Parameterization Method for Control Rod Position Indication

作　　者：申鹏飞 张成龙 张鹏 周梦飞 袁媛 刘国明 霍小东 王侃[2] SHEN Pengfei;ZHANG Chenglong;ZHANG Peng;ZHOU Mengfei;YUAN Yuan;LIU Guoming;HUO Xiaodong;WANG Kan(China Nuclear Power Engineering Co.,Ltd.,Beijing 100840,China;Department of Engineering Physics,Tsinghua University,Beijing 100084,China)

机构地区：[1]中国核电工程有限公司,北京100840 [2]清华大学工程物理系,北京100084

出　　处：《原子能科学技术》2024年第7期1452-1458,共7页Atomic Energy Science and Technology

摘　　要：微型堆中控制棒棒位的准确探测对于微纳型核能系统的远程实时监测和无人化智能化运营至关重要,也会影响功率在线监测的精度。本文提出了一种谐波参数化方法,将高阶谐波拟合为控制棒棒位的多项式函数矩阵,构造探测器响应方程,通过搜索棒位以最小化残差来实现精准的控制棒棒位预测,同时可得到对应的高阶谐波及堆芯重构功率。基于棱柱式气冷堆模型完成验证,数值结果表明,预测棒位的平均偏差为1.6 cm,预测精度较高;相比于固定高阶谐波,节块级功率重构的最大均方根相对误差从6.1%降至3%以内,最大相对误差从14.5%降至5%以内。这些结果验证了谐波参数化方法预测控制棒棒位以及改善堆芯功率重构精度的可行性,并为后续气冷微堆在线监测及故障诊断提供了一种思路。The accurate indication of control rod positions plays a pivotal role for remote real-time monitoring and self-intelligent operation of nuclear energy systems.In current pressurized water reactor systems,control rods operate in harsh environments under high temperature,high pressure,and high radiation.Typically,non-contact rod position detectors or position encoders are used to monitor the position of control rods.Nevertheless,numerical methods for predicting control rod positions have gradually emerged,showcasing notable advantages.The prismatic super-safe gas-cooled reactor(referred to as gas-cooled micro reactor)is one of the movable advanced micro nuclear reactor types,employing TRISO dispersed fuel with excellent safety features,cooled by helium gas,and possessing inherent safety characteristics.Based on the structural characteristics of the gas-cooled micro reactor,a harmonic parameterization method was proposed.Firstly,the process began with the preparation of high-order harmonic libraries at different rod positions(30-170 cm)using the Monte Carlo method.Secondly,the most influential high-order harmonics,identified through power reconstruction effectiveness,were selected.Thirdly,harmonic parameterization fitting calculations were performed after completing the harmonic selection.The main content of harmonic parameterization was to obtain continuous high-order harmonics with rod position by fitting the high-order harmonics of discrete rod positions using a polynomial fitting method.Fourthly,after establishing the high-order harmonics as a function of control rod positions,the study statistically derived the response matrix of external detectors using the Monte Carlo method.Finally,integrating this response matrix with the least squares method facilitates the resolution of the detector response equation.This methodology culminates in the successful prediction of control rod positions via the minimum residual approach.Simultaneously,corresponding high-order harmonics and core power reconstruction could be obt

关 键 词：气冷微堆 谐波参数化方法 控制棒棒位预测 功率重构 

分 类 号：TL424[核科学技术—核技术及应用]