本文为挪威北极圈大学（作者：Simon Kleppevik Skaga）的硕士论文，共101页。

本文对无人机在风力涡轮转子叶片超声脉冲无损检测中的应用进行了可行性研究。由于风力涡轮机的初始布置成本很高，而且由于尺寸和离岸位置的增加，因此必须在这些设备的10-30年寿命内对其进行适当维护。运行和维护成本可占总发电成本的25 - 30%（Martinez Luengo等人，2016年），其中风机转子叶片可被视为最关键的部件，占制造成本的15 - 20%。因此，通过状态监测提高风机转子叶片的运行和维护效率可以产生可观的财务效益。

目前，无人驾驶飞行器（UAV）正应用于风力涡轮机的目视和热成像检查。这些结构状态监测技术确实有严重的局限性，因为无法通过目视检查由玻璃纤维层压板制成的叶片内部组件状态。然而，脉冲超声回波技术已被证明是风机转子叶片检测的高效方法。超声波传感器需要与被检测材料表面接触，我们在本文中研究了无人机实现快速、安全和可靠检测风机转子叶片的潜力。

本可行性研究探讨了玻璃纤维层压板（尤其是Lyngen Plast A/S生产的玻璃纤维）超声波检测的适用性。首先，我们对模拟的分层缺陷进行了手持超声检测，寻找电压-时间图上的损伤指示。其次，我们通过3点弯曲试验对27mm厚的样品造成损伤，测量了相应的超声波脉冲回波响应。第二个实验是使用风暴反重力无人机重复进行的，通过初步的仪器测试得出了有希望的结果。

对本研究可行性的一个重大挑战是操作风险。我们使用SWIFT和Bow-Tie方法对无人机的预期运行进行了初步和定性的风险评估，给出了两个重要的风险缓解措施。风险降低：“设计无人机应对风机转子叶片的冲击，”风险预防：“开发风机现场的风况统计数据，计算低风险飞行日期。” 本文介绍了上述措施的实施情况、结果的质量、无人机飞行的经验和概念考虑，最后得出结论，并提出今后研究的课题方向。

In this thesis, we have conducted a feasibility study on UAV application for ultrasonic pulsed non-destructive testing of wind turbine rotor blades. Due to the high initial cost of wind turbines, and their decreasing availability due to increasing size and offshore locations, it is imperative to properly maintain these structures over their 10-30-year lifetime. Operation and maintenance costs can account for 25-30% of the overall energy generation costs (MartinezLuengo, et al., 2016), where the wind turbine rotor blade can be considered the most critical component, accounting for 15-20% of the manufacturing costs. Thus, an increase in O&M efficiency of wind turbine rotor blades through condition monitoring can yield substantial financial benefits. Currently, Unmanned Aerial Vehicles (UAV) are in use for visual and thermography inspection of wind turbines. These techniques for structural condition monitoring does have serious limitations, as the condition of internal components in blades, built from glass fibre laminates, cannot be visually inspected. However, pulsed ultrasonic echo technique have proven highly efficient for wind turbine rotor blade inspection. The ultrasonic transducer requires surface contact with the examined material, and we investigated the potential of UAV implementation for fast, safe and reliable measurements of wind turbine rotor blades. This feasibility study investigates the applicability of ultrasonic testing of glass fibre laminates, specifically glass fibre produced by Lyngen Plast A/S. Firstly, we conducted handheld ultrasonic tests on simulated delamination defects, looking for damage indications on a voltage-time graph. Secondly, we induced damage on a 27mm thick sample through a 3-point bending test and measured the echo response from the ultrasonic pulse. The second experiment was repeated using a Storm AntiGravity UAV, producing promising results with preliminary instrumentation. A significant challenge to the feasibility of this study was the operational risks. We carried out a preliminary and qualitative risk assessment of the intended UAV operation by using the SWIFTanalysis and Bow-Tie method. The results were two important risk mitigating measures. Risk reductive: “Design UAV for impact with wind turbine rotor blades,” and risk preventive: “Develop statistical data on wind conditions at wind turbine site, calculate low-risk dates for flight.” The implementation of the said measures, quality of our results, experiences from the UAV flight and concept considerations are presented throughout this paper. In the end, a conclusion is drawn and topics for future studies is presented.

1 引言

2 文献回顾

3 研究方法

4 研究结果

5 讨论

6 结论

7 参考文献 

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