基于多通道模态分析的输电线路舞动特征识别

Identification of galloping characteristics of a transmission line based on multichannel modal analysis

采用随机减量法(RDM)从实测输电线路舞动位移信号中提取非受迫振动信号,将其作为特征系统实现算法(ERA)的输入,实现对舞动频率、振型和阻尼比的识别。利用Matlab编制相应的识别软件,通过梁的振动试验验证了方法和软件的正确性。针对真型试验输电线路六分裂线路段位移时程多通道实测结果,采用获得的参数识别方法和软件,识别得到该线路舞动事件的频率、振动形态以及线路的阻尼比。该方法和软件为实际线路舞动特征参数的识别提供了重要手段。

With the random decrement method （RDM） , non-forced vibration response signals were extracted from galloping displacement signals of a transmission line. The galloping frequencies, vibration modes and damping ratios were identified using the eigensystem realization algorithm （ERA） with input of non-forced vibration signals. The identification software was coded with Matlab, it was verified with beam vibration tests. Further, by means of the developed software, the frequencies, vibration modes and damping ratios of the six real bundle conductor lines were identified. The proposed method and the developed software provided an important means for the identification of galloping characteristics of real transmission lines.