综合模态控制力下压电致动器的优化布局

Optimal placement of piezoelectric actuators using synthetic modal control force

针对智能挠性结构中致动器的优化布局问题,在分析挠性结构动力学方程和状态空间方程的基础上,采用模态理论,对系统控制矩阵进行奇异值分解,提出一种表征最大综合模态控制力的评价准则,该评价准则兼顾保留模态和截断模态对模态控制力的影响,综合考虑模态权重.最后以粘贴有压电致动器/应变传感器的挠性梁为例,通过理论计算和改进的遗传算法进行优化分析,得到综合模态控制力最大时压电致动器的布局位置,并建立实验测控系统进行验证.实验结果表明:采用优化结果中的致动器布局时,系统具有较好的综合模态控制力,控制效果也更优,所提出的评价准则和优化方法是可行的.

This paper dealt with the optimal placement of actuators in smart flexible structures. Based on the analysis of dynamic equations and state space equations of flexible structures, the modal theory was adopted and the singular value decomposition of control matrices was employed. Then, a criterion of the maximum synthetic modal control force was proposed. The criterion involved the effect of reserved and residual modes to the modal control force. Meanwhile, modal weights were considered. Finally, a flexible beam with piezoelectric actuators/strain sensors was chosen as an example, theoretical calculations and the improved genetic algorithm were used for the optimal analysis. Thus, the optimal positions of piezoelectric actuators with maximum synthetic modal control force were found, and an experimental system was set up to verify the proposed method. The experimental results demonstrate that the system has a good synthetic modal control force and control effect by using the optimal placement result of actuators. The proposed evaluation criterion and optimal method is feasible.