风电塔筒上声发射信号的衰减研究

研究了声发射(AE)信号在风电塔筒中的传播衰减规律,测定了实际的距离衰减关系,并采用小波分析方法对所采集的AE信号进行分层分析。结果得出,AE信号在焊缝处较母材处明显,漆面对信号的传播距离有一定的影响,在塔筒中最远可达6 m;断铅信号通过焊缝的能量频段主要在d4和d3频段,断铅信号未通过焊缝的能量频段主要在d3和d1频段;低频信号在通过焊缝时能量急剧降低,漆面使低频信号和d3频段信号的能量有一定降低。以上结论可以作为现场塔筒动态监测中传感器的布置依据,并可以作为信号源分析和定位的参考条件。

Damping Study on Sound Transmitting Signal of Wind Power Tower Drum

We mainly study spread decay rule of acoustic emission (AE) signal in wind power tower drum,test real relation between distance and decay,and analyze collected AE with stratification by wavelet analysis.We have conclusion that AE at welding joint is more obvious than that at base metal;paint has some effect on propagation distance of signal,up to 6m in tower drum;energy frequency band of lead-break signals through welding joint is at d4 and d3,lead-break signals blocked before welding joint is at d3 and d1;energy of low frequency dramatically drops when travelling through welding joint;paint makes energy of low frequency signal and d3 frequency band lower.Above conclusions can be as basis of sensor during site tower dynamic monitoring,also be reference condition of signal source analysis and location.