全相位Hv频响函数估计在MIMO随机振动试验控制中的应用

摘要

Multi-input and multi-output (MIMO) random vibration test control is affected by the accuracy of frequency response function (FRF) estimation, and which is furthermore in fluenced by signal noise and spectrum leakage. Hv estimation is used to suppress signal noise, and then all-phase FFT spectrum analysis method which can decrease spectrum leakage is induced to construct all-phase Hv FRF estimation, as is used to improve FRF estimation and then to improve MIMO random vibration test control. At last a two-input two-output contrast test about Hv FRF estimation and all-phase Hv FRF estimation is implemented on a steel cantilever beam, the estimation results are used into MIMO random vibration test control, the control results are improved when all-phase Hv FRF estimation is used.%首先选用对噪声抑制效果较好的Hv估计方法,然后引入对泄露有明显抑制效果的全相位FFT频谱分析方法,构成全相位Hv频响函数估计方法,改善了频响函数估计效果,减小了频响估计误差对MIMO随机振动试验控制效果的影响.最后在钢质悬臂梁上做两输入两输的Hv估计和全相位Hv估计的对比试验以及两种估计结果在MIMO随机振动试验控制的应用效果,试验结果验证了全相位Hv频响函数估计对改善了随机振动试验控制效果的有效性.