沸水式反應器蟻群最佳化演算法燃料佈局與控制棒佈局設計之研究

Automatic Boiling Water Reactor Loading Pattern & Control Rod Pattern Design using Ant Colony Optimization Algorithm

王政德(Cheng-Der Wang)

指導教授 ： 林強

國立清華大學/原子科學院/工程與系統科學系/博士(2011年)

https://doi.org/10.6843/NTHU.2011.00151

摘要

沸水式反應器燃料再裝填的爐心設計包括燃料佈局設計與控制棒佈局設計，燃料佈局設計在於燃料束的排列組合，目的在找出一個燃料佈局具有足夠的停機餘裕與熱限值餘裕，以確保可以成功設計出合於設計要求且週期長度足夠的控制棒佈局。控制棒佈局設計則是要決定控制棒插入的深度，在每個燃耗點的熱限值如：最小臨界功率比（MCPR）、最大線性熱產生率（MLHGR）、最大平面線性熱產生率（MAPLHGR）要符合設計要求，停機餘裕與週期長度也要符合設計要求。
本研究是以分等螞蟻系統（rank-based ant system, RAS）做為沸水式核電廠燃料佈局與控制棒佈局自動化設計工具的搜尋方法，分等螞蟻系統是蟻群最佳化演算法的一種，適合用來處理最佳化問題，此演算法可納入啟發式的知識與經驗以減少計算時間。在燃料佈局方面，本研究在每一個八分之一爐心的位置上，以蟻群最佳化演算法的機率選擇方式，選擇一根燃料束來放置，其他的七個對稱區域則將同一種型態的燃料束放到對稱的位置上。直到所有位置都已放置燃料束，以黑林燃耗計算週期長度、黑林燃耗週期結束時的熱限值與燃料週期開始時的停機餘裕來評估燃料佈局，並做為費洛蒙濃度更新的依據。在控制棒佈局方面，沸水式核電廠控制棒佈局是依A2-B1-A1-B2或A1-B2-A2-B1的棒序來設計，當一個控制棒佈局產生後，必需以SIMULATE-3程式計算軸向功率分佈、有效中子增殖因數、停機餘裕以及三個熱限值，用以評估此控制棒佈局並更新費洛蒙濃度。本方法以核二廠的兩個燃料週期作驗證，可在合理的計算時間內設計出合於要求的燃料佈局，並可成功的以這些燃料佈局設計出符合設計要求且週期長度足夠的控制棒佈局。

關鍵字

燃料佈局 ； 控制棒佈局 ； 沸水式反應器 ； 蟻群最佳化演算法 ； 分等螞蟻系統 ； 品質函數

並列摘要

The reload design of a boiling water reactor (BWR) consists of fuel loading pattern design and control rod pattern design. The fuel loading pattern design is to permute the fuel assemblies so that shutdown margin requirement is fulfilled and the thermal limit margin is good enough to guarantee the satisfactory control rod pattern design. The control rod pattern design is to determine the inserted depth of control rods at each exposure point so that the thermal limits such as minimum critical power ratio (MCPR), maximum linear heat generation rate (MLHGR), and maximum average planar linear heat generation rate (MAPLHGR) meet the margin requirement and shutdown margin and cycle length are fulfilled.
Automatic design of boiling water reactor loading pattern and control rod pattern were developed using the rank-based ant system (RAS) which is a variety of ant colony optimization (ACO) algorithm. The ACO algorithm is an effective optimization algorithm for combinatorial optimization problem and the heuristic rules of ACO algorithm were adopted to reduce search space and computation time. In loading pattern design, to reduce design complexity, fuel assemblies (FAs) were chosen to load the positions of one-eighth core geometry using probabilistic solution construction of ACO algorithm and then the corresponding fuel assemblies were loaded into the other part of the core. When the pattern was determined, Haling cycle length, the thermal limits at the end of cycle, and beginning of cycle (BOC) shutdown margin (SDM) were calculated using SIMULATE-3 code, which were used to evaluate the loading pattern for updating pheromone concentration of ACO algorithm. In control rod pattern design which followed either the A2-B1-A1-B2 or A1-B2-A2-B1 sequence in this study. After the control rod pattern was determined, the axial power distribution, effective multiplication factor (keff), shutdown margin, and three thermal limits were calculated using SIMULATE-3 code, which were then used to evaluate the control rod pattern and update the pheromone concentration. The developed design methodology was demonstrated using two fuel reload cycle of Kuosheng nuclear power plant. The results show that the designed satisfactory reload design with an acceptable cycle length can be achieved within a reasonable computation time.

並列關鍵字

Loading Pattern ； Control Rod Pattern ； Boiling Water Reactor ； Ant Colony Optimization Algorithm ； Rank-Based Ant System ； Quality Function

參考文獻

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