大型ナトリウム冷却高速炉の安全設計評価

Safety design evaluation of a large-scale sodium-cooled fast reactor

山野 秀将   ; 久保 重信* ; 島川 佳郎*

Yamano, Hidemasa; Kubo, Shigenobu*; Shimakawa, Yoshio*

FBRサイクル実用化研究開発第1期において、安全性に関する開発目標を達成しうる大型ナトリウム冷却高速炉の安全設計要求を構築するとともに、代表的な設計基準事象に対して安全解析を実施し、プラント成立性の見通しを得た。

A conceptual design study and related R&D for a large-scale sodium-cooled fast reactor (JSFR) are carried out in the framework of fast reactor cycle technology development project. As a next generation plant, JSFR adopts a number of innovative technologies in order to achieve economic competitiveness, enhanced reliability and safety. This paper describes the safety requirements for JSFR conformed to the defense-in-depth principle in IAEA. Specific design features of JSFR are passive shutdown system and re-criticality free concept against anticipated transient without scram accident in beyond design-based events. Safety analyses were also performed for representative design-based events: control rods withdrawal, primary pump seizure and loss-of-offsite power accidents. All analytical results showed to meet tentative safety criteria with expected reactor trip signals.