基于演变谱理论和正交化HHT法的冲击响应谱时域信号合成方法

A time domain signal synthetic method for shock response spectrum based on evolutionary spectra theory and orthogonal HHT

冲击响应谱时域信号是一类典型的非平稳信号,正交化HHT(Hilbert-Huang transform)法是进行非平稳信号时频分析的好方法。文章首先对冲击响应谱试验机实测到的时域冲击信号进行了正交化HHT频谱特性分析,然后将演变谱理论和正交化HHT法相结合,对实测的时域冲击信号进行了人工合成。频谱分析表明:合成的时域冲击信号与实测信号具有较好的一致性,且在信号的非平稳模拟方面,明显优于传统的三角波合成方法。最后,以该方法合成的时域信号为数据基础,进行了冲击响应谱的统计拟合,得到了冲击响应谱数学模型,结果可作为相关试验的输入条件。

The time domain signal of the SRS（Shock response spectrum） is a typical non-stationary signal, and the orthogonal HHT （Hilbert-Huang Transform） method is used for the time-frequency analysis of non-stationary signals. The time domain signal measured from the shock response spectrum test machine is selected as a case, the time-frequency characteristics are analyzed by the orthogonal HHT method. Then combined with the advantages of the evolutionary spectra theory and the orthogonal HHT method, a method for the simulation of the shock response signal is proposed. It is shown that for the synthetic sample, the time-frequency distribution is consistent with the original shock response signal, and is better than the traditional triangle wave synthesis method in non-stationary process simulations. At last, based on a large number of synthetic samples, a mathematical model of the SRS and its corresponding fitting parameters are presented; and the results can provide a useful reference for the related fields.