基于综合模态能的海上风电支撑结构损伤识别研究

Damage identification of support structures for offshore wind turbines based on comprehensive modal energy

文章研究了基于模态能的海上风电支撑结构损伤识别方法。利用结构损伤前后模态能的变化,构建了一种综合模态能损伤判别指标。该指标的最突出特点是同时使用了结构的模态应变能和模态动能。通过引入统计假设检验,给出了该损伤指标的判别阈值。为验证该方法的有效性,开展了三脚架式海上风电支撑结构的数值和试验研究。结果表明,文章所提出的综合模态能指标可有效地识别海上风电支撑结构的损伤;与传统的模态应变能法相比,该方法具有更强的噪声鲁棒性。

The damage identification method based on modal energy is studied for support structures of offshore wind turbines. Based on the change of the modal energy before and after the structural damage, a comprehensive modal energy index is constructed. The most prominent feature of this index is the simultaneous use of the modal strain energy and the modal kinetic energy of the structure. By introducing the statistical hypothesis test, the discrimination threshold value of the damage index is given. In order to verify the method, numerical and experiment studies are conducted for tripod-type support structures of offshore wind turbines. Results show that the proposed comprehensive modal energy index is effective for damage identification of support structures for offshore wind turbines. In addition, compared with the traditional modal strain energy method, the proposed method is more robust to noise.