【作者】 张永生；

【导师】 王煜；

【作者基本信息】 哈尔滨工业大学 ， 控制理论与控制工程， 2006， 硕士

【摘要】 该论文介绍了一种反馈空间H_∞控制器对控制目标进行减振,在文中运用了一个柔性悬臂梁作为控制对象,同时用压电陶瓷贴片作为驱动器和传感器。从理论上来说,用模态分析法对柔性结构进行分析会产生无穷多个模态,但是为了控制的目的,无穷多个模态通过移除更高阶的模态会被简化在我们所关注的频率带宽内,但是直接的降阶会极大的扰乱模型传递函数零点的配置,为了解决这个问题,论文运用了一种方法,这种方法的主要思想是通过加入一个选通项使得被移除的高阶模态模型对我们所关注的频带内的模型模态影响最小,这个选通项加入到柔性结构模态模型中去修正了我们所关注的频率带宽的零点配置。这个被修正过的模态模型被用来设计空间H_∞控制器。设计控制器的目的是使闭环系统的空间H_∞范数最小,从而确保整体结构在一种平均意义上的减小。最后控制器用仿真进行实现和确保悬臂梁有良好的鲁棒性能。从中可以看出,对于某一种类型的结构,运用空间H_∞控制器是有良好的减振效果的。更多还原

【Abstract】 This paper introduces a feedback spatial H_∞controller to suppress vibration of a flexible cantilever beam using collocated piezoelectric actuator-sensor pairs. The modal approach to modeling of the structure results in infinite-dimensional models, for control design purposes, the infinite-dimensional model is simplified by removing higher modes which lie out of the bandwidth of interest. The direct truncation can considerably perturb the zeros of the truncated model. For settling the problem, this thesis applies the method of minimizing the effect of removed higher order modes on the low-frequency dynamics of the truncated model by adding a feedthrough term to the low order of the system. The feedthrough term is incorporated into the flexible-structure model to correct the locations of the in-bandwidth zeros. The corrected model is then used to design spatial H_∞controller.The controller is designed to minimize the spatial H_∞norm of the closed-loop system to ensure average reduction of vibration throughout the entire structure. The final controller is numerically implemented and the results illustrate the robust control performance of a cantilevered beam type structure. It is possible, for certain mode, to obtain the very satisfactory result of vibration reduction.更多还原