本研究根據核能研究所(Institute of Nuclear Energy Research, INER)之核能三廠(Maanshan Nuclear Power Plant, MNPP)功率運轉活態安全度評估研究內容，並依照電廠之緊急運轉程序書(Emergency Operating Procedures, EOP)模擬電廠在發生蒸汽產生器管束破裂事故(Steam Generator Tube Rupture, SGTR)時的電廠狀況。本研究利用RELAP5-3D/K程式模擬蒸汽產生器管束破裂事故下，針對運轉員執行高壓注水(High-Head Safety Injection, HHSI)、緊急降溫降壓(Emergency Cooldown and Depressurization, Emergency CND)、和燃料更換水儲存槽(Refueling Water Storage Tank, RWST)再補水(replenishment)等人為緩解措施的時間，並將程式輸入參數的不準確度(Uncertainty)納入考量，計算事故發生後之最高燃料棒護套溫度(Peak Cladding Temperature, PCT)，並依此量化前述三項措施的人為失誤機率(Human Error Probability, HEP)。

本研究利用人為認知可靠度(Human Cognitive Reliability, HCR)模式，設定人為緩解措施執行時間的機率分佈，結合對RELAP5-3D/K結果有決定性影響的參數之機率分佈，以蒙地卡羅取樣(Monte Carlo Sampling)，並進行多次程式運算。運算的結果依照事件樹(Event Tree)頂端事件的成功準則為基準，判斷人為緩解動作發生失誤的機率。並以此結果重新計算事故序列之爐心熔損頻率(Core Damage Frequency, CDF)。根據模擬結果，總計124組案例均沒有失敗導致爐心溫度上升至1,200°F以上，顯示運轉人員應該有足夠的時間判斷與執行緩和措施，人為失誤機率僅剩執行時的誤失。

This study is based on the research conducted by the Institute of Nuclear Energy Research (INER) on the safety assessment of power operation activities at the Maanshan Nuclear Power Plant (MNPP). It simulates the plant's condition in the event of a Steam Generator Tube Rupture (SGTR) accident, following the Emergency Operating Procedures (EOP) of the power plant. The RELAP5-3D/K program is used to simulate the SGTR accident and evaluate the plant's response, including the actions taken by operators such as High-Head Safety Injection (HHSI), emergency cooldown and depressurization (emergency CND), and replenishment from the refueling water storage tank (RWST). The study also considers the uncertainties in input parameters and calculates the Peak Cladding Temperature (PCT) of fuel rods after the accident, quantifying the Human Error Probability (HEP) associated with the aforementioned mitigation measures.

The study employs the Human Cognitive Reliability (HCR) model to establish the probability distribution of the execution time for human mitigation actions. Monte Carlo sampling is used to combine this with the probability distribution of parameters that have a decisive impact on RELAP5-3D/K results. Multiple program calculations are performed. Based on the success criteria of the top event in the Event Tree, the probability of human error in the execution of mitigation actions is determined. This result is then used to recalculate the Core Damage Frequency (CDF) of accident sequences. According to the simulation results, in all 124 cases, there were no failures leading to a core temperature rise above 1,200°F, indicating that operators have sufficient time to assess and implement mitigation measures, with the remaining probability of human error being associated with missed opportunities during execution.

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