核反應器中子監測系統之數位化研究

A Study of Digital Neutron Monitoring System for Nuclear Reactor

謝孟寰(Meng-Huan Hsieh)

指導教授 ： 周懷樸 ； 曾訓華

國立清華大學/原子科學院/工程與系統科學系/碩士(2010年)

摘要

核子工程領域中，反應器功率監測是相當重要的一環，由於反應器內之中子流量正比於反應器功率，寬程中子監測系統 (Wide Range Neutron Monitor, WRNM)即扮演偵測反應器核心功率的重要角色，其功能有二，第一為提供反應爐運轉時的功率變化與反應爐功率周期資訊，第二為提供反應爐保護系統之急停訊號，以控制阻棒的抽取時機。
傳統之寬程中子監測電路，多仰賴全類比電路系統技術，對於不同的反應器系統，類比電路系統往往需要做全面性地修改與調校，難度較高，相對之下，數位電路系統對於不同反應器系統之修改彈性較佳，不需做高難度地修改，即可針對不同的反應器中子流量量測使用，另外，類比電路系統對各種雜訊之抗干擾性皆不如數位電路系統，有可能因現場輻射環境的干擾等造成讀出數據之誤差。
有鑑於積體電路技術的進步，現代類比數位轉換器的效率、系統記憶體空間、以及數位信號處理能力，皆有大幅地提升，可達到同傳統類比電路系統即時處理的能力，再加上數位電路系統可調整度彈性大、抗雜訊能力高等優點，評估傳統寬程中子監測系統數位化之可行性，並著重於數位化Campbell定理的研究，為本研究之目標。

關鍵字

寬程中子監測 ； 坎貝爾定理 ； 數位化 ； 中子流量 ； 數位示波器 ； 清華水池式反應器 ； 第一核能發電廠 ； 核反應器

並列摘要

Power monitoring system is one of the most important parts of nuclear planet. Due to the fact that the neutron flux in the reactor core is proportional to the reactor power, the wide range neutronmonitor system (WRNM) plays an important role in controlling and monitoring the situation of the reactor core. It can provide two main functions. First, it offers the information about the power variation; second, it provides the trip signals for the reactor protecting system in order to adjust the control rod.
The classic WRNM systems were built by analog circuit system for the most parts. It is difficult to tune the parameters among different reactor system. Comparing to the analog cir-cuit system, the digital circuit system is flexible to redesign the parameters, providing a wide adaptability to different reactor systems; Moreover, analog circuit system is sensitive to the noise more than digital circuit system does, hence the readout could have errors for analog circuit system.
Thanks to the rapid growing of IC technology, the efficiency of ADCs, the memory spaces of system, and the capability of realizing DSP algorithms becomes better and better these years. Using digital system to achieve the real-time processing as what can be done by classic analog system is possible for today’s WRNM. Therefore, the goal of our research is to evaluate the feasibility of digitizing the classic WRNM system, especially for the Campbell technique realization.

並列關鍵字

Wide range neutron monitoring ； Campbell theorem ； Digitization ； Neutron flux ； Digital Oscilloscope ； THOR ； Chin-Shan NPP ； LabVIEW ； Nuclear reactor

參考文獻

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