基于Hilbert-Huang变换的非线性振动系统的研究  

Research on HHT-based nonlinear vibration system

作　　者：肖立波[1] 任建亭[1] 

机构地区：[1]西北工业大学振动工程研究所,西安710072

出　　处：《计算机应用研究》2011年第3期880-882,共3页Application Research of Computers

基　　金：国家自然科学基金重大资助项目(50475147)

摘　　要：基于Hilbert-Huang变换(Hilbert-Huang transform,HHT)提出了一种时频信号处理方法,并应用于非线性振动系统的识别。HHT利用由信号局部最大值与最小值得到的当前时间尺度去筛选不同时间尺度、频率从高到低顺序排列的各分量。另一方面,由于HHT不是利用先验的基函数与函数的正交性提取各分量成分,从而能得到比较准确的系统特征与非线性估计。对于单自由度非线性系统的参数识别,该方法处理了一有阻尼的自由瞬态响应与稳态响应,以及利用由小扰动分析得到的依赖幅度的动态特性来确定非线性的类型和级别以及系统的参数。非线性系统的数值仿真算例表明,提出的方法对不同的非线性动态系统能够提供准确的识别。This paper presented a time-frequency signal processing method based on HHT for identification of nonlinear vibration systems.HHT used the current time scales that revealed by the signal＇s local maxima and minima to sequentially sift components of different time scales,starting from high-to low-frequency ones.On the other hand,because HHT did not use pre-determined basis functions and function orthogonality for component extraction,it provided more accurate time-varying amplitudes and frequencied of extracted components for accurate estimation of system characteristics and nonlinearities.For parametric identification of a nonlinear one-degree-of-freedom system,the method processed one free damped transient response and one steady-state response and used amplitude-dependent dynamic characteristics derived from perturbation analysis to determine the type and order of nonlinearity and system parameters.Numerical simulations of several nonlinear systems show that the proposed method can provide accurate parametric and non-parametric identifications of different nonlinear dynamical systems.

关 键 词：正交性 非线性 参数识别 动态特性 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]