对风能发电机组的结构进行了简单介绍，对其上经常失效的结构件以及其材料、热处理工艺和失效形式进行了归纳。选取了机组上应用数量较多、作用比较重要的高强度螺栓作为该讲的主要内容，对螺栓在机组上的应用特点、失效特点、结构特点、受力特点及其失效原因进行了较为详细的论述。结合多年的失效分析经验，采用实际案例的方式，重点介绍了机组上螺栓最常出现的两种失效形式——疲劳断裂和氢脆型断裂，并对这两种失效产生的根本原因进行了剖析，最后提出了避免机组上螺栓失效的预防措施。

The structure of wind turbine generator system (WTGS) is briefly introduced, and the structural parts that often fail on WTGS, as well as their materials, heat treatment process and failure modes were summarized. The high-strength bolts with a large number of applications and important functions on WTGS were selected as the main content of this lecture. The application characteristics, failure characteristics, structural characteristics, force characteristics and failure causes of the bolts on WTGS were discussed in detail. Combining years of failure analysis experience, actual cases were used to focus on the two most common failure types of the bolts on WTGS-fatigue fracture and hydrogen embrittlement fracture, and the root causes of the two failure were analyzed. Finally, preventive measures to avoid failure of bolts on WTGS were put forward.