應用應變響應擴展於離岸風機支撐結構局部破壞識別之可行性評估

台灣為了達成2025非核家園的能源政策，近年來積極發展離岸風電。離岸風機位處於大海中，承受的負荷大於陸域風機許多，其利用支撐結構承載各式環境載重及傳遞作用力，一旦支撐結構發生損壞，將造成災難性的故障。為了能監控離岸風電機組之健康狀況，及早察覺破壞發生，因此可靠的結構健康監測系統（Structural Health Monitoring System, SHMS）為一項研究的重點，以現今的破壞識別方法而言，以模態參數監測法占大宗，但此方法的缺點在於無法識別微小破壞發生。本研究提出了以應變響應擴展進行破壞識別的方法，具備識別結構微小破壞的能力，透過壓克力剛架試體進行實驗，利用切割缺口的方式製造人為破壞，證明此方法的可行性，並與有限元素模擬結果進行驗證。最後以3.6 MW套管式支撐結構有限元素模型進行案例演示，以確認此方法在真實結構之可行性。本研究所提出之創新的破壞識別方法可以有效識別微小破壞發生，並且定位破壞發生位置，應用於離岸風機支撐結構上將能及早識別損壞，有利於提高風電機組之使用年限。

關鍵字

離岸風機；結構健康監測；破壞識別；應變響應擴展

並列摘要

In order to achieve the energy policy of 2025 nuclear-free homeland, Taiwan has actively developed offshore wind power in recent years. The offshore wind turbine is located in the sea, the load is greater than that of the onshore wind turbine. It uses the support structure to carry various environmental loads and transmission forces. Once the support structure is damaged, it will be catastrophic failure. In order to monitor the health of offshore wind turbines and detect damage earlier, a reliable Structural Health Monitoring System (SHMS) is the focus of research. In current damage identification method, Modal parameter monitoring method is used in most cases, but the shortcoming of this method is that it cannot identify the small damage. This study proposes a method for damage identification based on Strain Expansion-Reduction Approach, which provides the ability to identify small damages in structures. The experiment was carried out through the acrylic frame test, and the artificial damage was made by cutting the notch, which proved the feasibility of the method and verified with the finite element simulation results. Finally, a case demonstration was carried out with a finite element model of a 3.6 MW offshore wind turbine jacket substructure to confirm the feasibility of this method in the real structure. The innovative damage identification method proposed by this research can effectively identify the occurrence of small damage and locate the location of the damage. It will be able to identify the damage early on the offshore wind turbine support structure, which is beneficial to improve the service life of the wind turbine.