運轉員與數位儀控系統介面互動表現對核能電廠安全影響之研究

Study of Nuclear Power Plant Safety Effect by Interactions between Operator and Digital Instrumentation and Control System

黃揮文(Hui-Wen Huang)

指導教授 ： 施純寬 ； 易俗

國立清華大學/原子科學院/工程與系統科學系/博士(2007年)

摘要

核能電廠儀控系統數位化後可提供更強大的整體運轉功能，及具有親和力之人機介面，運轉員可藉著電腦系統獲取更多資訊。然而儀控系統數位化時遭遇以下三點問題：(1)軟體共模失效、(2)運轉員與數位儀控系統介面互動過程失誤、與(3)軟體失效之不可偵測性，可能擊潰防禦階層，增加分析多樣性與深度防禦效能困難度。其中第(2)項運轉員與數位儀控系統介面互動影響最大，因為第(1)項與第(3)項對應至多樣性與深度防禦，而最後最重要一層為如何確認運轉員與數位儀控系統介面互動。本研究發展出一套整合性方法論以評估運轉員與數位儀控系統介面互動表現對核能電廠安全影響，並可據以提出改善建議。此整合性方法論包括組件層級的軟體故障樹分析與系統層級之序列樹方法及電廠電腦模擬程式分析方法。軟體故障樹可釐清數位儀控系統內軟體失效過程與肇因，序列樹方法可鑑別設計基準事件中運轉員與各多樣性與深度防禦層級數位儀控系統間之互動關係，電廠電腦模擬程式分析方法可進一步分析運轉員在數位儀控系統失效時可供運用之備用設施與容許手動動作之時間。將本方法論應用於評估數位化核能電廠深度防禦設計之效能，應可提升核能電廠運轉安全。運轉員在操作高度自動化之數位儀控設施時，將可更加信賴核能電廠。

關鍵字

運轉員 ； 數位化儀控系統 ； 多樣性與深度防禦 ； 軟體故障樹 ； 序列樹方法 ； 核能電廠電腦模擬分析

並列摘要

The digitalized Instrumentation and Control (I&C) system of Nuclear power plant can provide more powerful overall operation capability, and user friendly man-machine interface. The operator can obtain more information. However, while I&C system being digitalized, three issues are encountered: 1) software common failure, 2) the interaction failure between operator and digital instrumentation and control system interface, and 3) the non-detestability of software failure. These failures might defeat defense echelons, and make it more difficult to analyze the perfiormance of Diversity and Defense-in-Depth (D3). This research developed an integrated methodology to evaluate nuclear power plant safety effect by interactions between operator and digital I&C system, and then propose improvement recommendations. This integrated methodology includes component level software fault tree, and system level sequence tree method and nuclear power plant computer simulation analysis. Software fault tree can clarify the software failure structure in digital I&C systems. Sequence tree method can identify the interaction process and relationship among operator and I&C systems in each D3 echelon in a design basis event. Nuclear power plant computer simulation analysis method can further analyze the available backup facilities and allowable manual action duration for the operator when the digital I&C fail to function. Applying this methodology to evaluate the performance of digital nuclear power plant D3 design, could promote the nuclear power plant operation safety. The operator would trust the nuclear power plant than before, when operating the highly automatized digital I&C facilities.

並列關鍵字

Operator ； Digital Instrumentation and Control System ； Diversity and Defense-in-Depth ； Software Fault Tree ； Sequence Tree Method ； Nuclear Power Plant Computer Simulation Analysis

參考文獻

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