摘要
针对风洞试验模型系统辨识不准确的问题,利用自适应LMS(least mean square)滤波器模型对跨声速风洞模型进行系统辨识。由于实测信号中存在多模态耦合,为了提高系统辨识精准度,首先对输入输出信号作了FRF(frequency response analysis)分析得到试验模型俯仰方向前两阶模态,其次利用快速Fourier变换进行模态解耦,接着利用自适应LMS滤波器模型、传递函数模型、多项式模型对俯仰方向单模态进行系统辨识,最后得到了基于自适应LMS滤波器模型的俯仰方向一阶、二阶模态滤波器系数。通过对比不同数学模型的输出与输入之间的相关系数和均方误差及辨识结果,表明自适应LMS滤波器模型具有更高的系统辨识精准度和更简洁的数学模型结构。为后续风洞试验模型振动主动控制计算法的设计提供有力支撑。
Here,aiming at the problem of inaccurate system identification for wind tunnel test models,an adaptive least mean square(LMS)filter model was adopted to perform system identification for transonic wind tunnel models.Due to presence of multi-modal coupling in actually measured signals,firstly,in order to improve the accuracy of system identification,frequency response analysis(FRF)was performed for input and output signals to obtain the first two modes in pitch direction of the test model.Secondly,fast Fourier transform was used to do modal decoupling.Then,adaptive LMS filter model,transfer function model and polynomial model were used to do system recognition for single mode in pitch direction.Finally,the first and second order modal filter coefficients in pitch direction were obtained based on adaptive LMS filter model.By comparing correlation coefficients between output and input,mean square errors and recognition results of different mathematical models,it was shown that adaptive LMS filter model has higher system identification accuracy and a more concise mathematical model structure;it can provide strong support for design of active vibration control algorithms of subsequent wind tunnel test models.
作者
李斌斌
寇西平
吕彬彬
余立
杨兴华
路波
曾开春
LI Binbin;KOU Xiping;L Binbin;YU Li;YANG Xinghua;LU Bo;ZENG Kaichun(High Speed Aerodynamics Research Institute,China Aerodynamics Research and Development Center,Mianyang 621000,China;School of Aeronautics,Northwest Polytechnic University,Xi’an 710000,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2024年第3期164-170,共7页
Journal of Vibration and Shock
