风电叶片疲劳过程中的声发射特性研究-北京声华.PDF

信号分析与处理 中国第十五届声发射学术研讨会 风电叶片疲劳过程中的声发射特性研究 张鹏林，李梅，王汝姣，姜宜成 兰州理工大学 省部共建有色金属先进加工与再利用国家重点实验室 兰州 730050 摘 要：借助中材科技（酒泉）风电叶片有限公司的叶片疲劳试验平台，采用声发射技术对风电叶片疲劳加载的两个不 同阶段（20 万次和 180 万次）分别进行了一段时间的声发射信号实时监测，并对叶片在两个不同疲劳时期的声发射信 号进行了小波分析和 Hilbert-Huang 变换(HHT)，结果表明：随着循环载荷的累积，叶片的材料和结构健康状况明显下降。 叶片振动 20 万次时已经有裂纹萌生，典型的裂纹信号频率有 40KHz 和 80KHz，当振动至 180 万次时，叶片已经出现微 裂纹快速扩展和局部脱胶等典型的疲劳特征，损伤信号较 20 万次时明显增多，信号的能量和幅值也较高。 关键词：声 发射；风电叶片；疲劳；小波分析；Hilbert-Huang 变换 中图分类号：TK83 Acoustic Emission Characteristics Research of Wind Turbine Blades in The Fatigue Test Zhang Pinglin Li Mei Wang Rujiao Jiang Yicheng Lanzhou University of Technology, State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou 730050 Abstract: In this subject, with the help of wind turbine blade fatigue test platform of Sinoma technology (Jiuquan) wind power blade Ltd, acoustic emission(AE) technique is applied to achieve real-time monitoring in the two different stages(blade vibration of 2.0×105 times and 1.8×106 times respectively) of fatigue loading to wind turbine blade. Then, the AE signals collected in the two different stages of fatigue test were processed by wavelet analysis method and Hilbert-Huang transform. The results show that: with the accumulation of cyclic loading, the health condition of structure and material of blade decline obviously. There have been cracks initiation when the blade vibrates 2.0×105 times, and the typical crack signal frequency is 40KHz and 80KHz.When the blade vibrates 1.8×106 times, blade has appeared typical fatigue characteristics, such as the rapid expansion of micro cracks and local debonding etc. Compared to the state of 2.0×105 times, the damage signals increased