在采用加速度传感器的振动主动控制中,为了克服加速度信号经数值积分分别得到位移信号和速度信号时的累积误差,并考虑系统中的输入时滞,基于等维法(Reduction Method)和输出状态导数反馈思想,提出一种连续时滞加速度反馈控制器设计方法。为了在实际测控系统中便于计算机操作,应用积分离散化方法,将该连续控制器转换为离散形式。以粘贴有压电陶瓷和加速度传感器的智能梁为仿真控制对象,采用该控制器控制含输入时滞的智能梁的自由振动系统,并与加速度反馈控制器控制的同一时滞系统的稳定性及控制效果作对比。仿真结果表明,所提时滞加速度反馈控制器具有较宽的参数稳定区间和较好的控制效果,且当系统时滞存在较小扰动时,该控制器对时滞量具有一定的鲁棒性。
This paper is devoted to design the time-delayed controller using direct acceleration feedback for active vibration control systems. By means of the reduction method and the output state-derivative feedback control approach, a new continu- ous time-delayed acceleration feedback controller is proposed without the inclusion of the displacement and velocity signal, so that the accumulation errors caused by once and twice integration of the acceleration signal can be avoided. In order to cater for the requirement of computer control, the discrete form of the proposed controller is obtained by the discretization of the corresponding integral system equation. The developed time-delayed feedback controller is examined by the computer simula- tion, with a special focus on the control performance of a cantilever beam with the piezoelectric actuator and the acceleration sensor. Simulation results demonstrate that the proposed controller can effectively reduce the free vibration response of the intelligent cantilever beam, and compared with the acceleration feedback controller, it has wider parametric stable intervals and better control effects. In addition, the proposed controller exhibits good robustness to the inaccuracy of the estimated time delay of the controlled system.