多输入多输出随机振动试验变参数PID控制

 对多输入多输出(MIMO)随机振动试验控制的基本过程进行了系统分析。定义了一种新的在对数坐标下的控制误差表达式,然后在控制算法中引入了新的比例-积分-微分(PID)控制策略,并给出了PID参数随误差变化的规律。以悬臂梁为控制对象,完成了两输入两输出随机振动试验。结果表明：变参数PID控制方法能在保证快速均衡的基础上,有效地减小功率谱和参考谱之间的相对误差以及加速度总均方根值的控制误差,提高随机振动试验的控制精度。

PID Control with Variable Arguments for MIMO Random Vibration Test

The basic procedure of a multi-input multi-output (MIMO) random vibration test is analyzed systematically in the article. A definition of control error under logarithmic coordinates is provided, and a new proportion-integration-differentiation (PID) control strategy is introduced into the control algorithm. The law of the error-dependent arguments for the PID controller is then presented. A two-input two-output random vibration test is performed with a cantilever beam to verify the proposed control method. The experimental results show that the variable argument PID control method not only has the ability to make rapid tradeoff between the control and the reference spectra but it can also reduce effectively the errors between them as well as the control error of the total root mean square of acceleration. Therefore the accuracy of random vibration test control is improved.