核电纵深防御理论的新探索

New Exploration of Defense-in-Depth Theory for Nuclear Power Plant

纵深防御(DID)理论在经历核电之初的主动探索和三次核事故的被动改进,其层次数量和要求逐渐增多,使核电厂设计越来越复杂。工程设计和新堆型研发的实践中也暴露出一些问题,导致核电经济性提升和创新技术应用受到强烈掣肘。为了探索理论升级的可能,以使其反映最新的技术和认知水平,向着“越简单越安全”的方向发展,在充分认识纵深防御概念重要性和局限性的基础上,本文从方法和技术两个维度提出核电纵深防御理论改进的两个方向:一是建立风险指引型纵深防御策略框架,并给出渐进的实现方案;二是基于实体屏障固有安全性提升的简化纵深防御,对固有安全能力提升的潜在技术方向进行讨论。

The defense-in-depth(DID) theory has been developed with initiative exploration at the birth of nuclear power plant and passive modification after three nuclear accidents, and the layers and requirements of defense are increasing which makes the safety design of nuclear power plant more and more complicated. Several problems are exposed during the engineering design and development of the reactor system, including the economic cost and application of innovative technologies. In order to explore the possibility of upgrading the theory to reflect the up-to-date technology and knowledge and to achieve the purpose of “the simpler, the safer”,the prospect for improving the DID theory are discussed from two dimensions of analysis method and new technologies. One way is to establish a risk-informed DID framework with step-by-step approaches;the other is to simplify DID by improving inherent safety of physical barriers.