风力发电机接闪系统失效风险定量评估方法研究

Study on Quantitative Evaluation Methodology for Failure Risk of the Lightning Attachment Systems on Wind Turbines

雷害问题严重影响风机的正常运行,但针对风机接闪系统的失效风险,目前鲜有定量的分析和评估方法。基于先导发展物理模型,提出风机接闪系统雷击屏蔽失效率的定义和计算方法,并通过叶片雷击模拟实验验证了方法的有效性。比较分析了不同接闪系统型式叶片的雷击屏蔽失效率,并考虑了风机旋转角度和海洋盐雾附着对雷击屏蔽失效率的影响。分析表明,相比于接闪器–引下线结构型式和叶尖包覆铜网型式,采用主梁包覆铜网型式的叶片雷击屏蔽失效率最小,但综合考虑经济性和易维护性,推荐采用叶尖包覆铜网的接闪系统型式。提出的定量分析方法可为风机叶片接闪系统的优化设计和失效风险评估提供依据。

Lightning-induced damage on the wind turbines will greatly affect their normal operation. However, there are few quantitative methodologies available for risk assessment of the lightning attachment systems on wind turbines. Based on the leader development model, a quantitative method was presented to calculate the lightning shielding failure rate of the lightning attachment system on wind turbines, and the effectiveness of the proposed method was verified by physical simulation experiments. Taken into the influence of the blade orientation and sea salt fog contamination, the lightning shielding failure rates of the blades regarding different lightning attachment systems were comparatively analyzed.The results show that, the lightning shielding failure rate of the main beam-covered copper mesh blade turns to be the lowest compared to the other two types, however, from a comprehensive point of view on economical benefit and convenient maintenance, the blade tip coated with copper mesh is recommended for practical applications. The definition and assessment method proposed in this paper provides a theoretical basis for optimal design and failure risk assessment of the lightning protection system on the wind turbine blades.