Application of an improved HHT method for modal parameters identification of structures with closely spaced modes

作者：Huang Tian Li^*; Qiu Fa Qiang; Lou Meng Lin

来源：Journal of Central South University(Science and Technology), 2011, 42(7): 2054-2062.

• Basic principles
• Basic procedure
• Closely spaced modes
• Empirical mode decomposition
• Hilbert Huang transforms
• Impulse excitations
• Intrinsic mode functions
• Modal parameters
• Modal parameters identification
• Mode separation
• Orthogonal empirical mode decomposition
• Wave group

In the modal parameters identification proceeding using Hilbert-Huang transform (HHT) method, there exist some problems such as the deficiency of mode separation of empirical mode decomposition (EMD) and the non-othogonality between the intrinsic mode IMF) components. For these two problems, the improved Hilbert-Huang transform method which combined the wave group (WG) signal preceding method with the orthogonal empirical mode decomposition (OEMD) was proposed. The basic principle of OEMD and the wave group (WG) signal preceding method were introduced, and the basic procedure of modal parameters identification using the newly improved HHT method was proposed and applied in the modal parameters identification of structures. A 3-DOF structure with closely spaced modes during the impulse excitation was used to validate this method. The results show that the proposed improved HHT method can identify the modal parameters efficiently and is better than the traditional HHT method.

• 出版日期2011
• 单位中南大学; 同济大学