基于非线性扩张状态观测器的四面固支板自抗扰振动主动控制

Active disturbance rejection vibration control for an all-clamped plate based on nonlinear extended state observer

针对四面固支板非线性、强耦合和模型不确定等问题,提出一种基于非线性扩张状态观测器的自抗扰振动主动控制策略.首先通过激光测振仪对四面固支板进行模态分析并建立数学模型,测得其固有频率及振型,以此优化驱动器与传感器的布置位置;然后引入非线性扩张状态观测器对建模误差、高次谐波和外部激励等内外干扰进行估计,并通过前馈通道进行实时补偿,消除其对系统的影响;最后基于压电片驱动器、加速度传感器以及NI PCIe采集卡在Matlab/Simulink的desktop real-time环境中搭建半实物实时平台,对提出的策略进行实验验证.结果表明该方法具有良好的抗干扰能力,对四面固支板结构的振动具有良好的控制效果.

Considering the nonlinearity,strong coupling and model uncertainty in an all-clamped plate,an active disturbance rejection control method based on a nonlinear extended state observer is proposed in this paper.A laser vibrometer is applied to measure the natural frequency and mode shape of the all-clamped plate in order to optimize the position of the piezoelectric actuators and accelerometers.Then,a third-order nonlinear extended state observer is introduced to estimate the internal and external disturbances,i.e.,modeling errors,high-order harmonics and external excitation,etc.And the influences of the internal and external disturbances are eliminated by compensating them via the feed-forward channel in real time.Finally,a semi-physical real-time platform is built in Matlab/Simulink real-time environment based on piezoelectric actuators,accelerometers and NI PCIe capture card to test and verify the proposed method.The results show that the proposed control method has an excellent ability to control disturbance and has a significant performance on vibration suppression.