Wavelet power spectrum smoothing for random vibration control

The response of a large-size cooling tower with 250m high subjected to the seismic action are investigated by both random vibration theory and response spectrum method. Shell element is taken to model the tower body, and beam element is used for the circular foundation and supporting columns. The earthquake motion input is a colored filtered white noise model and mode superposition method is adopted to analyze the random response of the large-size cooling tower. The paper presents the power spectrum density functions (PDF) and standard deviation of the displacement of the top and characteristic node, and the analysis results indicate that the results of the stationary random vibration theory and the response spectrum method are the same order of magnitude. The power spectrum density function of the bottom node stress is obviously bigger than the one at the top and the throat, and the random response of meridonal stress is dominated at the top. In addition, the peak frequency position of the power spectrum density function is different from the corresponding stress.

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Research on Random Vibration Control Algorithm Based-on EV Model

Proceedings of the 2nd International Conference on Electronic and Mechanical Engineering and Information Technology (2012) ◽

10.2991/emeit.2012.29 ◽

2012 ◽

Author(s):

Haoyang Yu ◽

Guangfeng Guan ◽

Chenlu Feng

Keyword(s):

Vibration Control ◽

Control Algorithm ◽

Random Vibration ◽

Ev Model

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Analysis of low damping ratios in multi-exciter stationary non-Gaussian random vibration control

Journal of Vibration and Control ◽

10.1177/1077546319898561 ◽

2020 ◽

Vol 26 (17-18) ◽

pp. 1463-1470 ◽

Cited By ~ 3

Author(s):

Ronghui Zheng ◽

Huaihai Chen ◽

Min Qin ◽

Andrea Angeli ◽

Dirk Vandepitte

Keyword(s):

Vibration Control ◽

Random Vibration ◽

Response Spectra ◽

Spectral Lines ◽

Control Algorithms ◽

Calculation Error ◽

Spectral Matrix ◽

At Resonance ◽

Input Signals ◽

Non Gaussian

This article investigates the influence of low damping ratios on the performance of the multi-exciter stationary non-Gaussian random vibration control system. The basic theory of the multi-exciter stationary non-Gaussian random vibration method is reviewed first, and then the influences of low damping ratios on multi-output spectra and kurtoses are analyzed. The low damping ratios cause an ill-conditioned problem which will make the drive spectral matrix solution inaccurate; thus, some spectral lines located at resonance peaks in the response spectra cannot be modified within the preset tolerances by the control algorithms. The regularization method is used to alleviate the calculation error. The output kurtoses are dependent not only on the characteristics of the system but also on the input signals. It is found that the kurtosis control will be intractable if the damping ratios are very low. A two-input two-output cantilever beam simulation example is described to illustrate the analysis results.

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