考虑结构高阶振型信息的AMD低维控制器设计

AMD low-dimensional controller design considering structural high modes information

为减小AMD控制系统的时滞影响,一般需对被控结构模型作减维处理,但是在减维过程中系统较小特征值对应相关的结构信息被直接舍弃,将使得低维结构缺少原结构高阶振型等信息,导致低维模型精度降低,影响控制器的设计准确性。在基于均衡截断法和极点配置算法的低维控制器设计中,重新考虑舍弃的结构高阶信息,该信息包括原结构的高阶自振频率、高阶阻尼比以及高阶振型模态信息等,并在进行极点配置之前,先考虑该部分信息对系统极点位置的影响,在控制系统的设计阶段消除了低维模型精度低的不利影响。以10层结构为例,基于改进的低维控制器,以系统控制效果、AMD控制力及行程峰值为指标,分析了低维模型对AMD控制系统性能的影响;并以4层框架实验模型的AMD控制系统为实例,验证上述数值分析结论的正确性。

To reduce the influence of AMD control systemts time delay, the dimensionality of controlled structure model is needed to reduce. However, structural information which is corresponded to system＇s small characteristic values is directly abandoned in the process of dimensionality reduction, and the low-dimensional structure will lack high modes and other information of original structure. That is to say, the process becomes inaccurate and thus the design of the controller will be influenced. Based on the balanced truncation method and pole assignment algorithm, the low-dimensional controller is designed and the discarded structural information which includes the natural frequencies, damping ratios and modes information of the original structure is reconsidered. In addition, in order to reduce the effect of the inaccuracy at the design stage, part of information which will affect the pole position of the system is considered before performing the pole. The ten-story structure is taken as an example, in which the system control effect, the peak force and peak schedule of AMD are used as the control indexes to analy- zes the effects on dimensionality of reduced structural model to the improved low-dimensional controller. Furthermore, the four-layer experimental frame＇s AMD control system is taken as an example to test the conclusions.