中文摘要：

国际原子能机构（InternationalAtomicEnergyAgency，IAEA）认为小型模块化反应堆具有很好提高核能安全性、经济性和防止核扩散的能力，是未来核能最具发展前景的堆型之一。为适应未来核能发展的需求，提出了一种铅铋冷却氮化物燃料小型模块化反应堆（SmallModularPb．BiCooledReactorwithNitrideNuclearFuel，SMPBN）设计方案，并利用PIJ组件计算程序和CITATION堆芯计算程序对SMPBN的物理特性和安全特性，包括反应性系数及其随燃耗变化、卸料燃耗、功率峰因子、燃料转换比和停堆余量等进行了深入分析。通过分析，认为SMPBN在20年寿期内，具有很好的燃料转换能力，不需要换料，反应性波动很小，反应性系数均为负值，具有固有安全性，符合国际上第四代反应堆的要求。

英文摘要：

Background： The small modular reactor is considered by Intemational Atomic Energy Agency （IAEA） to be one of the most promising nuclear reactors in the future, which could not only improve the safety and economy of nuclear energy, but also prevent the nuclear proliferation. Purpose： This paper puts forward a small modular Pb-Bi cooled reactor with nitride nuclear fuel （SMPBN） which is designed to meet the requirements for nuclear energy improvement. Methods： The physical characteristics and security features of the SMPBN were analyzed by PIJ and CITATION, including the reactive coefficient and its change with bumup, discharge bumup, power peak factor, fuel conversion ratio and shut-down allowance, etc. Results： The SMPBN is expected to possess a good fuel conversion capability during the life-time of 20 a, with a small reactive fluctuation and a negative reactivity coefficient, which means that the SMPBN has inherent safety. Conclusion： It is considered to be satisfying the requirements of the G-IV, which provides a valuable reference for development of small modular fast neutron reactor in future.