MIMO随机加正弦振动试验J-阻抗复合控制算法

Jacobi-Impendence Compound Control Algorithm of MIMO Sine on Random Mixed Mode Vibration Test

以多输入多输出(multiple-input multiple-output,简称MIMO)随机加正弦混合试验控制系统中信号分离方法、控制策略及试验为研究对象,提出了针对混合型振动试验的分离控制策略,采用相关积分法分离混合信号中的正弦信号与随机信号成分。推导了MIMO线性随机振动系统的反馈控制方程,提出了控制目标针对性更强的Jacobi控制算法。分析了多点正弦振动试验中存在的过修正问题,基于压缩因子修正提出阻抗控制方法,并将其与Jacobi算法共同应用于混合试验系统。以悬臂梁为试验对象,开展J-阻抗复合控制算法在两输入两输出随机加正弦混合试验系统中应用验证。结果表明,算法可以有效地抑制超标谱线,并将结果控制在容差带内,为混合振动试验控制提供有力的理论支撑。

The mixed signals separation method,vibration control strategy and test verification are all the important problems in multiple input multiple output mixed mode vibration system with random and sine signals.Based on the whole separation method,the correlation integral algorithm is proposed to be applied in the separation of sine and random signals.The self-spectrum and cross-spectrum including coherence and phase messages are both key elements of reference power spectral density matrix,so that the Jacobi method is obtained according to the multiple input multiple output linear vibration theory.The method has more pertinence to the specific elements of spectral matrix.There is excessive updating problem in sine vibration test,and this can destroy the vibration devices and make high level noises.To solve the problem,the impendence algorithm is proposed by introducing the compression updating factor.In the last part of the paper,a two input two output vibration system is established on a cantilever beam to verify the J-impendence method and the results show that the method has high control precision and can be applied in actual engineering application.