基于变调节因子的Morlet小波在密集模态辨识中的应用

Application of close modal parameter identification based on Morlet wavelet with variable regulatory factors

研究了基于Morlet小波的模态参数的识别方法。针对密集模态识别的问题,提出了通过引入带宽参数和中心频率两个变调节因子来调节Morlet小波的波形,提高了频域和时域的识别分辨率。使用MATLAB编程实现了算法的求解辨识过程,分析了所提算法中影响因子的作用。通过实例分析,对比了三自由度线性阻尼系统基于小波变换算法和基于频响函数算法的识别结果,验证了小波变换算法的正确性;通过圆盘实验实际测试数据的试验模态分析结果,充分验证了所提算法在密集模态识别中的有效性。

Modal parameter identification is researched based on Morlet wavelet transformation. Aiming at the close modal identification problems, the frequency bandwidth and center frequency are introduced to adjust the waveform of wavelets and improve the identification resolution ratio of time domain and frequency domain. The algorithm of identification process is realized by MATLAB, and actions of the influence factors are analyzed for the proposed algorithm. By the example, the 3-dof linear damp system is researched based on wavelet transformation and traditional frequency function respectively, the correctness is verified. Through the actual measurement data from the round disk experiment, the modal identification results confirm the effectiveness of the proposed algorithm in close modes.