Abstract The Korean nuclear power regulatory body issued the standard design approval for a 1500-MW advanced power reactor in 2014. The reactor was designed based on a four-train independent safety concept with a passive auxiliary feedwater system. Its full power risk, or core damage frequency (CDF), was determined to be significantly lower than that of the Advanced Power Reactor 1400 (APR1400) used in Units 3 and 4 of the Shin-Kori Nuclear Power Plant. However, because the ratio of the CDF contribution to the internal full power to that of the low-power and shutdown (LPSD) is 17:83, the risk during LPSD operation requires further assessment and reduction. In this study, we investigated design alternatives for reducing LPSD operation risks and analyzed the associated sensitivities. We propose various design alternatives, and their combinations, which are analyzed based on the reduction effect they have on the CDF for plant operating states and on initiating events during LPSD operation. The proposed alternatives, and their combinations in particular, exhibited significant reductions in LPSD CDF, indicating high potential applicability.

中文翻译：

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具有被动辅助给水系统的 1500 兆瓦先进动力堆低功率和停堆运行的风险降低设计替代方案

摘要 韩国核电监管机构于 2014 年颁发了 1500 MW 先进动力堆的标准设计批准书。该反应堆是基于四列独立安全概念设计的，带有被动辅助给水系统。其全功率风险或堆芯损坏频率 (CDF) 被确定显着低于新古里核电站 3 号和 4 号机组中使用的先进动力堆 1400 (APR1400)。但是，由于CDF对内部全功率的贡献与低功率关断（LPSD）的贡献比为17:83，因此LPSD运行期间的风险需要进一步评估和降低。在这项研究中，我们研究了降低 LPSD 操作风险的设计替代方案，并分析了相关的敏感性。我们提出各种设计方案及其组合，根据它们对电厂运行状态的 CDF 和 LPSD 运行期间的起始事件的减少影响进行分析。提议的替代方案，特别是它们的组合，表现出 LPSD CDF 的显着降低，表明具有很高的潜在适用性。