本研究使用美國核管會最新開發之最佳估算熱水流系統程式TRACE模擬分析台灣電力公司馬鞍山電廠全黑事故，以及斷然處置程序之執行，並探討斷然處置程序在面對複合式災變發生時的事故緩和能力。馬鞍山電廠為美國西屋公司所設計之三迴路壓水式電廠，其一號機於民國90年時曾經發生過一起為時兩小時之電廠全黑事故。本研究先利用經過電廠起動測試驗證之馬鞍山電廠TRACE輸入模式進行民國90年馬鞍山電廠全黑事故之模擬，隨後再利用此輸入模式模擬馬鞍山電廠假想電廠全黑事故、全黑事故執行斷然處置程序以及斷然處置相關之靈敏度分析。
日本福島核子事故顯示出電廠在面對超過設計基準事故時緊急替代設備與人員訓練的不足。面對類福島事故，除了強化電廠設施外，亦必須要具備一套明確且快速的處置策略。台灣電力公司提出斷然處置程序之目的為在事故發生初期便立即進行蒸汽產生器以及反應爐之降溫降壓操作，若廠內正規注水系統不可用，則同時利用替代注水設備執行蒸汽產生器或反應爐注水，以確保核燃料被水覆蓋。在本研究所假設之前提下，模擬結果顯示斷然處置程序應用於電廠全黑事故時，可成功防止核燃料裸露。
考慮到替代注水設備以及列置時間可能受限於廠內設施毀損程度，本研究探討可確保核燃料被水覆蓋之最小替代注水流量以及最慢替代注水準備時間。模擬結果顯示，每台蒸汽產生器替代注水流量至少必須大於40 gpm，且必須最遲於電廠全黑發生後3小時內準備完成並且注入。此外，本研究亦評估發生反應器冷卻水泵軸封洩漏事故對反應爐水位造成之影響。模擬結果顯示，若發生21 gpm/pump之洩漏事故，反應爐水位將於70小時後降至燃料頂端，對於此，廠內緊急交流電源必須盡快恢復，或是進行反應器冷卻水系統替代注水，以防止核燃料裸露。

This research focuses on the analysis of station blackout (SBO) accident in Maanshan nuclear power station and the mitigation capability of SBO response strategy so called the ultimate response guideline (URG) by using TRACE code. Maanshan NPS is a Westinghouse 3-loops PWR power station. In year 2001, a real SBO accident happened in unit 1 of Maanshan NPS. This research uses the input model that has verified with plant startup test to simulate the SBO accident happened in 2001, and then analyze hypothetical SBO accident with URG and other sensitivity studies by using this verified model.

Main action of URG including steam generator (SG) and reactor coolant system (RCS) depressurization, and SG injection by using alternate equipment if onsite regular injection systems aren’t available. The simulation results of SBO accident with URG show that, by executing the URG during SBO can keep the nuclear fuels covered with water and prevent fuel cladding from damage.

Considering the SG injection capability and preparation time may be an uncertainty during SBO, the research evaluates the minimum required injection flow rate to be 40 gpm/SG and the preparation time no more than 3 hours in order to keeps the fuels covered with water. Furthermore, if a 21 gpm/pump leakage rate of reactor coolant pump (RCP) seal LOCA happens during SBO with URG executed, simulation result shows that reactor water level will drop to TAF in 70 hours. Therefore, RCS alternate injection and quick restoration of onsite AC power should be considered to maintain the reactor water level if RCP seal LOCA happens.

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