Iterative extraction method for maximum energy of measured signals of offshore structures

Abstract

The invention relates to a method for iteratively extracting the maximum energy of a marine structure measured signal, comprising: calculating the autocorrelation function of the original dynamic response signal, solving the power spectral density, and determining the maximum energy component in the original dynamic response signal; discretizing the original dynamic response signal , and perform complex exponential fitting under the low-order state-space model to extract the maximum energy component in the original dynamic response signal; set the decomposition stop criterion, increase the order of the state-space model, and repeat the decomposition process to quantify the decomposition accuracy; The maximum component component is constructed, and the remaining dynamic response signal is used to replace the original dynamic response signal, the above decomposition process is repeated, and the maximum energy component of the remaining dynamic response signal is iteratively extracted to achieve a complete decomposition of the original dynamic response signal. The maximum energy component in each decomposition is determined based on the power spectral density function of the dynamic response, and the maximum energy component in the response is extracted iteratively by controlling the extraction precision, which improves the decomposition precision.

Description

technical field [0001] The invention belongs to the technical field of signal decomposition, in particular to a method for iteratively extracting the maximum energy of a marine structure measured signal. Background technique [0002] The dynamic response of marine engineering structures contains both structural information and excitation information. If the relevant information can be accurately extracted from the dynamic response signal of the structure, the relevant characteristics of the structure and excitation can be further obtained. Currently, this problem is solved by decomposing the raw dynamic response signal into a series of component components. However, due to the complex environment in which marine engineering structures are located and long-term combined effects of unstable wind, wave, current and other loads, the dynamic response obtained from the test contains a large number of noise components, and it is very difficult to use traditional signal decompositio...

AI Technical Summary

Problems solved by technology

Although the empirical mode decomposition method is based on decomposing signals one by one from high frequency to low frequency, due to the influence of the complex marine environment where the marine engineering structure is located, the problem of mode aliasing usually occurs, which leads to poor decomposition effect, and even There is a problem of decomposition failure

[0004] In marine engineering, due to the complex marine environment, the measured signal of the structure usually contains a large amount of noise components, and it is often difficult to achieve satisfactory accuracy when using the above two types of signal decomposition methods for analysis

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