中文摘要：

针对故障树的建立中所存在的主观性、模糊性、重复性以及覆盖性等问题，提出了一种基于HAZOP建立数字化变电站故障树的系统性方法。先通过5HAZOP的引导词与数字化变电站相联系，确定必要的偏差事件；然后分析得出偏差产生的原因和结果，以此来确定故障树的父子关系；最后按照流程图建立完整的故障树，并以数字化变电站与数字化保护为例，示例了完整的建模过程。通过此方法可以规范化地建立故障树，为发现数字化变电站系统内固有的或潜在的各种危险因素提供了科学、合理的手段。

英文摘要：

Aiming at the issues of subjectivity, ambiguity, redundancy and coverage, this paper presents a systematic approach to constructing fault trees of digital substations based on HAZOP. First, the necessary deviation events are determined through associating the HAZOP guide words with the digital substation. Then the causes and results of the deviation are analyzed in order to determine the paternity of the fault tree. Finally, the complete fault tree is constructed according to the proposed flow chart. To illustrate the effectiveness of the proposed approach, the overall model as well as the modeling process of the digital substation and digital protection system is presented. This method can establish fault tree normatively, and provide a scientific and rational way to identify the inherent or potential risks within the digital substation systems. This work is supported by National Natural Science Foundation of China （No. 50807037）.