基于Hammerstein模型的非线性气动弹性系统辨识  

Identification of Nonlinear Aeroelastic Systems Based on Hammerstein Model

作　　者：李治涛[1] 韩景龙[1] 员海玮[1] 

机构地区：[1]南京航空航天大学机械结构力学及控制国家重点实验室,南京210016

出　　处：《南京航空航天大学学报》2013年第1期14-20,共7页Journal of Nanjing University of Aeronautics & Astronautics

基　　金：国家自然科学基金(10872089;11102085)资助项目;高等学校博士点学科专项科研基金(20113218110002)资助项目

摘　　要：在非线性气动弹性系统的辨识中,Hammerstein模型常用来辨识系统的非线性部分,而假设其线性部分是已知的。本文以累积相干函数为准则,有效地选择非线性部分的基函数,减少辨识参数的数目;利用条件逆谱法得到系统线性部分的极点,并构造相应的正交基函数;基于Hammerstein模型,建立该非线性系统的参数化模型;用非迭代方法求解模型参数;从而提出了能够同时辨识系统线性和非线性部分的非迭代辨识算法。以俯仰方向含刚度五次非线性的二元翼段为例,验证了该辨识方法的有效性。In the identification of nonlinear aeroelastic systems, a Hammerstein model is used for identifying the nonlinear part of the system, and its linear part is assumed to be known in advance. The cumulative coherence function is considered as the criterion, and the base functions of its nonlinear part is effectively chosen in order to reduce the number of identified parameters. The poles of its linear part are obtained by the conditioned reverse path spectral method, and the correspondence orthonormal base functions are constructed. The parametric model of the system is built based on Hammerstein model. And the parameters of the model are solved by a non-iterative algorithm. Thus a non-iterative algorithm capable of simultaneously identifying the linear and nonlinear parts of the system is proposed. The validity of the identifying method is verified by using an example of a two-dimensional airfoil with the 5th nonlinearity of the stiffness in the direction of the pitch.

关 键 词：气动弹性 非线性辨识 条件逆谱法 HAMMERSTEIN模型 累积相干函数 

分 类 号：V211.47[航空宇航科学与技术—航空宇航推进理论与工程]