基于压电元件的柔性板H_∞鲁棒振动控制实验研究

Experimental Study of H∞ Robust Control for Flexible Plate Vibration System Based on Piezoelectric Chips

以一柔性板为对象进行了H∞鲁棒振动控制器的设计、仿真和实验研究。首先,利用多变量频域辨识原理,识别出以粘贴压电片作为传感器和作动器的柔性板实验系统前三阶模态的MIMO传递函数模型,接着,对具有乘型不确定性的板模型在干扰抑制、控制增益约束以及鲁棒稳定三方面进行频域加权整型,构建了H∞混合灵敏度控制系统;数值仿真验证了各权函数的合理性,初始外扰和随机外扰下的振动控制实验结果表明,相对LQR方法,H∞控制能使闭环系统在保持鲁棒稳定的前提下获得更好的性能,初始外扰下衰减时间缩短30s,随机外扰下降噪量提高4dB。

There are design calculations, simulation and tests of robust active vibration controllerbased on one flexible plate bended piezoelectric actuators and sensors. Firstly, the multi input multi output（MIMO） transfer function model of three modals of the plate vibration system was identified by the multivariable frequency--domain identification theory. Then, by means of frequency weighted transformation of the flexible plate model with residual modal multiplicative uncertainty according to the performance of disturbance suppression, control gain restrain and robust stabilization, a mixed sensitivity robust controller was established. The results of simulation proves the rationality of the controller and the weighted functions. After the active vibration control tests of initial disturbance and random disturbance, the results verify that compared to the LQR controller, the controller can achieve better performance under the condition of system robust stabilization, the attenuation time is shortened 30s, the noise reduction is increased 4dB.