多输入多输出正弦扫频试验控制新方法

研究了多输入多输出正弦扫频试验控制中信号发生、频响函数估计和控制算法等关键问题。针对步进式正弦扫频信号发生中因信号不连续而导致振动台或激振器发生冲击或损坏的问题，提出了两个不同频率的正弦信号平滑过渡的窗函数叠加延拓法，在满足扫频时间条件的同时也提高了试验控制精度；以单位正弦扫频信号作为激励，改变不同激励点的相位以产生满秩激励矩阵，运用相关积分法识别响应稳态正弦时域信号的幅值与相位，根据线性振动理论求解结构的频响函数；以多个控制点的幅值为控制对象，推导出扫频控制基本理论公式，通过参考值与反馈信号的比较来修正激励信号以满足试验条件。文末以一悬臂梁为研究对象，建立了两输入两输出正弦试验控制系统，结果表明本文提出的方法在扫频控制中取得良好的效果。

New Control Method for the MIMO Swept-sine Test

Swept-sine test is often applied in order to simulate the real vibration situations of aircrafts, vehicles, watercrafts, and electron devices. The article focuses on the the control method for the newly developing Multi-Input Multi-Output (MIMO) swept-sine test. A new method named Overlapped Windows and Extension (OWAE) is proposed to smooth the discontinuous signal segments of two sinusoid waves with different frequencies. The method can improve the control precision and meet the requirement of swept time. The uncorrelated integration method is used to identify the amplitude and phase of the steady state sine signal. The frequency response functions (FRFs) are calculated by the Linear Time Invariant (LTI) system theory. The formula with the amplitudes and phases as the control objects for MIMO swept-sine test is derived. The control signal is updated by comparing the feedback response and the reference. An example is given to simulate a two-input two-output swept-sine control system. The results show the validity of the raised control method.