针对直线电机驱动的HMD控制系统,推导了受控结构的运动控制方程,在LQG控制算法下根据控制力反馈方程分析了HMD控制改变结构参数的方式以及宏观减震机理,进一步采用扫频正弦波对仿真结构进行激励,分析不同频率激励下调节结构参数的方式及详细的减震机理.研究结果表明:当外部激励频率在低于结构第一频率的低频段时,HMD中AMD对结构的作用是增加结构的刚度和阻尼;随着频率的增加,HMD中AMD增加结构刚度及阻尼越来越大;当外部激励频率在频率共振区域内,增加结构的刚度和阻尼达到最大;当外部激励频率在高于共振频率的区域内,增加结构的刚度越来越小,最后变为负刚度,阻尼系数也逐渐减小.
For Hybrid Mass Damper (HMD) control system driven by linear motor, the motion equation of con- trolled system is formulated and the variation of the structural parameters and macroscopic shock absorption mechanism of HMD are analyzed by using LQG control algorithm according to the feedback equation of control force. Then, the variation of the structural parameters and detailed shock absorption mechanism of HMD are discussed by investigating the response of simulation structure controlled by LQG control algorithm under sweep sine excitation. Results show that the function of AMD driven by linear motor in HMD control system can in- crease the stiffness and damping of controlled strueture when the frequency of input excitation is less than the fundamental frequency of structure. With increasing frequency of input excitation, the effect of increasing the stiffness and damping under HMD becomes higher and higher, and the stiffness and damping under HMD rea- ches the peak when the frequency of input excitation is equal to the first frequency of structure. Within the range of higher than the natural frequency of structure, the effect of increasing the stiffness and damping under HMD becomes less and the increased stiffness becomes negative stiffness.