本研究論文的目的是為了作龍門電廠預期暫態未急停之相關事故分析。我們採用PCTRAN-ABWR為本論文的電廠模擬器,PCTRAN-ABWR是一套方便且系統要求低的模擬軟體,此軟體利用質量方程式與能量方程式兩種方程式來完成程式執行時所需的計算,大幅降低電腦計算時的負擔,普通的桌上型電腦即可使用此軟體快速地進行電廠事故模擬計算,原本的PCTRAN-ABWR程式中關於預期暫態未急停事故的相關邏輯並不夠完善,因此透過本研究論文來精進期預期暫態未急停相關事故邏輯以及設定點,並新增原PCTRAN-ABWR程式中所沒有的案例相關邏輯。 本論文將藉著二項重要工作來研究,分別為:(1)擴充PCTRAN-ABWR預期暫態未急停系統,包括替代性控制插棒系統、微調控制驅動插棒系統與備用硼液控制系統,依照龍門電廠最終分析報告第十五章第E節所描述之各個設定值作設定並模擬預期暫態未急停事故,使PCTRAN-ABWR分析預期暫態未急停事故的功能更加完備。(2)模擬龍門電廠最終分析報告第十五章第E節的事故並作暫態分析,透過與龍門電廠最終分析報告的暫態圖比較,確立精進過後的版本可以完善的模擬預期暫態未急停,並另外模擬主蒸汽管路斷管伴隨預期暫態未急停事故、飼水管路斷管伴隨預期暫態未急停事故及高壓注水系統單根管路斷管伴隨預期暫態未急停事故,此三件皆為beyond-DBA事故,透過這些事故的模擬讓我們了解電廠的深度防禦特性。
The purpose of this work is to perform an Anticipated Transient Without Scram (ATWS) safety analysis of Lungmen nuclear power plant (LMNPP) in Taiwan. PCTRAN-ABWR is a NPP transient and accident simulation code with high efficiency and convenience. Because PCTRAN-ABWR only consider mass equation and energy equation, it can simulate a variety of accident and transient conditions with little computer resources. In original version, the logics of ATWS are not enough perfect, therefore this work modified this code and added some new logics of ATWS events into modified PCTRAN-ABWR. This work performed by two parts as show as the following:(1)To improve the analyzed ability, the ATWS logics and set points in PCTRAN-ABWR code is modified including ARI, FMCRD and SLCS, according to Final Safety Analysis Report (FSAR) 15E.6.(2)Two ATWS cases with the following initiating events, Main Steam Isolation Valve Closure and Loss of Offsite Power selected from FSAR 15E.6, were performed to verify the modified PCTRAN-ABWR. These ATWS mitigation benchmarks show PCTRAN-ABWR has a good ability to simulate ATWS events and their mitigation functions of LMNPP design. In addition to the above DBA analyses, this work analyzed three beyond-DBA cases including Main Steam Line Break Loss-of-Coolant Accident (LOCA) combined with ATWS, Feed Water Line Break LOCA combined with ATWS, and High Pressure Core Flooder (HPCF) Line Break LOCA. The defense-in-depth in nuclear power plant could be observed in these transient analyses.