基于H_2/H_∞的双振动台解耦控制

Dual-Shaker Random Vibration Decoupling Control Based on H_2/H_∞

研究了基于次优Η2 /Η∞ 混合控制的振动台解耦控制器的设计方法 ,用缩减了高阶模态的降阶模型所设计的控制器对原系统进行解耦控制 ,引入了模型不确定性 ,克服了传统的基于模型逆的解耦控制系统鲁棒性能较差的缺点 ;利用双自由度控制结构的特点 ,将问题分解为Η2 和Η∞ 两个次优控制器的设计过程 ,简化了问题求解的复杂性 ;通过整形技术提高了解耦控制的效果 ;与基于 Riccati方程的求解方法相比 ,本文利用的线性矩阵不等式求解方法更具有灵活性和一般性 ;本文的仿真结果表明了次优Η2 /Η∞ 解耦控制方法不仅具有良好的解耦性能 。

A design approach to dual-shaker random vibration decou pling control with uncertainities of system is presented using a mixed Η 2/Η ∞sub-optimal control method for a two-degrees-of-freedom cont roller. A four-degrees-of-freedom lumped mass model of a simplified beam is s tud ied, the design procedure is reduced to an H ∞feedback and an H 2 tracking control problems because of the separation property of the control structure. And the controller is designed by considering the model for fi rst three vibration modes with loop shaping and by neglecting another high frequ ency mode or unmodeled dynamics.This approach is better than conventional one ba sed on the inverse of the model in stability robustness and causing no spillover phenomena while approximate decoupling is achieved using Η 2/Η ∞ sub-optimal controller via a reduced order model. Simulation result demons trats its efficiency of the real control objects.